AutoBee-design

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Design of Automated Beehive with Android Technology Lovely C. Almocera

Renz Claudel O. Arboleda Sarrah Kay S. Bravante Crecialene S. Dela Cruz

Technological Institute of the Philippines Quezon City

March, 2015

APPROVAL SHEET

This design project entitled “Design of Automated Beehive with Android Technology” is prepared by Lovely C. Almocera, Renz Claudel O. Arboleda, Sarrah Kay S. Bravante, and Crecialene S. Dela Cruz of the Computer Engineering Department was examined and evaluated by the members of the Student Design Evaluation Panel and is hereby recommended for approval.

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ENGR. RONNIE M. DYSANGCO Adviser

Panel Members:

ENGR . ALONICA VILLANUEVA ENGR . ARIEL E. ISIDRO

Member Member

ENGR. MARIA CECILIA A. VENAL Chair

TECHNOLOGICAL INSTITUTE OF THE PHILIPPINES Quezon City

Major (Capstone) Design Experience Information CP 520D2 DESIGN PROJECT 2

2nd _{Semester, SY 2013-2014}

Student/Team Group

Lovely C. Almocera Renz Claudel O. Arboleda Sarrah Kay S. Bravante Crecialene S. Dela Cruz

Design Title Design of Automated Beehive with Android Technology Program Concentration Area Embedded System

Design Objectives Project Objective

The general objective of this project is to design a device that can monitor the temperature, humidity and the weight of the beehive to meet the requirements needed by the client in accordance with codes of ethics, engineering standards and consideration of tradeoffs based on multiple constraints such as economic, sustainability and manufacturability. Specific Objectives

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 To design a prototype that could monitor the beehive temperature and humidity.

 To develop an Android application that would display the actual beehive frame’s status and measurement.

 To test and evaluate the accuracy of the prototype. Constraints

Economic

The components that were used for the building of the design project were put into consideration based on the client’s requirements and the availability of the components. The designers used the components that are not harmful to the client and the environment. Considering the cost of the components, the designers used not only the affordable materials, but also the précised functionality that was needed for the design.

Manufacturability

The manufacturability of the components would be highly affected depending on the availability of the materials. The capability of the design produced with the needed part and maintenance referred the design’s manufacturability.

Sustainability

The designers also considered the functionality of the device. The design project had an easy to use functionality and was environmentally friendly. Considering the procedures, the designers made sure that there are fewer procedures so that the client was able to understand and work with it without so much time wasted.

Standards

 3-1982 - IEEE Recommended Practice in the Selection of Reference Ambient Conditions for Test Measurements of Electrical Apparatus

The designers considered the standard during the measurement of temperature and humidity inside of a beehive. The standard was used in all three designs created by the designers since all designs has temperature and humidity sensor.

 ASTM E 74-02 American Society for Testing and Materials, 2002, Standard Practice of Calibration of Force

The designers used the standard for the calibration result for load cell sensor (weight sensor). All three designs used the ASTM E 74-02 standard since a weight sensor needed to be calibrated to give an accurate result of measurement.

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 IEEE standard 802.15.1 for Bluetooth Wireless Technology

The designers used the standard for the communication from the prototype to the Android application installed in an android device.

 UNIFORMAT II (E 1557) The designers took in consideration the standard construction of a beehive as to avoid harming not only the environment but also the bees itself.

 IEEE standards for In-System Configuration for Programmable Devices

The designers used the standard when working with a programmable device such as microcontroller that holds the instruction to make the prototype function according to the objective.

LIST OF FIGURES

Figure 1.1 Project Developments...2

Figure 3.1 Input-Process-Output...8

Figure 3.2 System Flowchart...10

Figure 3.3 Illustrative Diagram...11

Figure 3.4 (b) Load cell sensor...14

Figure 3.4 (a) Automated Beehive...14

Figure 3.5 Schematic Design of Automated Beehive with Android Technology using Load cell sensor...15

Figure 3.6(b) Torque Sensor...20

Figure 3.6(a) Automated Beehive Design 2...20

Figure 3.7 Schematic Design of Automated Beehive with Android Technology using Torque sensor...21

Figure 3.8.(b) Touch Sensor...26

Figure 3.8.(a) Automated Beehive Design 3...26

Figure 3.9 Schematic Design of Automated Beehive with Android Technology using Touch sensor...27

Figure 3.10 Graphical User Interface Design...30

Figure 3.11 Graphical User Interface Design Phases 2...30

Figure 3.12 Software Development Life Cycles...31

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Figure 4.2 Subordinate ranking of Torque sensor in economic cost...37

Figure 4.3 Subordinate ranking of Load cell sensor in manufacturability...38

Figure 4.4 Subordinate ranking of Touch sensor in manufacturability...39

Figure 4.5 Subordinate ranking of Load cell based on sustainability...40

Figure 4.6 Subordinate ranking of Touch sensor based on sustainability...41

Figure 5.1 Final Design Prototype...44

Figure 5.2 Digital Hygrometer...46

Figure 5.3 Portable Digital Weight Scale...46

Figure 5.4 The device was helpful to the user...50

Figure 5.6 The device can generate accurate results...50

Figure 5.7 The device is affordable...51

Figure 5.8 The device is easy to use...51

Figure 5.9 The software is easy to use...52

Figure 5.10 The output generated can easily transmit to android device...52

Figure 5.11 The device is safe for the user...53

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LIST OF TABLES

Table 3-1 Cost of Materials of Design 1...13

Table 3-2 Design 1 Specification of Materials of Design 1...17

Table 3-3 Cost of Materials using Torque Sensor...19

Table 3-4 Design 2 Specification and Cost of Materials using Torque Sensor...23

Table 3-5 Cost of Materials using Touch Sensor...25

Table 3-6 Design 3 Specification and Cost of Materials using Touch Sensor...29

Table 3-7 System Algorithms for the Design of Automated Beehive with Android Technology...32

Table 4-1 Designer Tabulation Form...35

Table 4-2 Initial Cost of each component...35

Table 4-3 Availability of the Materials...37

Table 4-4 Sustainability of components...39

Table 4-5 Tabulation of Trade-offs...41

Table 5-1 Accuracy Test for Temperature...48

Table 5-2 Accuracy Test for Humidity...48

Table 5-3 Accuracy Test for Weight...48

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LIST OF ABBREVIATIONS

ASTM American Society for Testing Materials CPU Central Processing Unit

I Current

IEC International Electrotechnical Commission IEEE Institute of Electrical and Electronics Engineer ISO International Organization for Standardization

KΩ Kilo Ohms

LCD Liquid Crystal Display MCU Microcontroller

MHz Mega Hertz

Ω Ohms

Php Philippine Peso

PIC Peripheral Interface Controller

R Resistance

RAM Random Access Memory

UART Universal Asynchronous Receiver/Transmitter

V Voltage

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Design of Automated Beehive with Android Technology...i

APPROVAL SHEET...ii

Major (Capstone) Design Experience Information...iii

LIST OF FIGURES...v

LIST OF TABLES...vi

LIST OF ABBREVIATIONS...vii

TABLE OF CONTENTS...viii

CHAPTER 1. PROJECT BACKGROUND...1

The Project...1

Project Objectives...1

The Client...2

Project Scope and Limitation...2

Project Development...2

CHAPTER 2. DESIGN INPUTS...5

Design Constraints...5

Design Standards...5

Software Requirements...6

Hardware Requirements...6

CHAPTER 3. PROJECT/ SYSTEM DESIGN...8

Input-Process-Output...8

System Flowchart...10

Illustrative Diagram...11

Hardware Design...12

Design 1: Using Load Cell...12

Prototype Design...14

Circuit Diagram...15

Specifications and Cost of Materials...17

Design 2: Using Torque Sensor...18

Project Design...20

Design 3: Using Touch Sensor...24

Project Design...26

Software Design...30

Graphical User Interface Design...30

Software Development Life Cycle...31

System Algorithm...32

Dataflow Diagram...32

CHAPTER 4. DESIGN TRADE-OFFS...34

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CHAPTER 5. FINAL DESIGN...44

Final Design...44

Test Procedures and Evaluation...45

Test Procedures...45

Test Evaluation...47

Test and Evaluation Results...47

Test Results...47

Evaluation Results...49

Conclusion...53

CHAPTER 6. BUSINESS MODEL...54

REFERENCES...55 APPENDICES...56 APPENDIX A...56 APPENDIX B...59 APPENDIX C...62 APPENDIX D...64 APPENDIX E...67

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CHAPTER 1. PROJECT BACKGROUND The Project

Based on Bee Community, the honey bee production plays an important role for biodiversity and agriculture. Bee colony’s contribution to the ecosystem shows its impact in almost 80% of plant families. With this scenario, bee farming molds to make its impact on the economic growth of honeybee production. The traditional process of honey bee extraction starts from the beekeeper that would monitor if the hive is already full of honey. If the beehive is ready for extraction, the beekeeper would take out the hive and check if there is presence of varroa mites. If positive, varroa mites would be removed from the hive using manual process; otherwise, it would proceed with the extraction process.

The traditional or manual process of extracting honey consumes time and effort since there is no available device or equipment in the market. In addition, temperature and humidity cannot be monitored by the beekeeper. Thus, production of honey may be affected.

Therefore, a device for automated beehive with the application of Android technology was designed. This would help the beekeeper in monitoring the average temperature and humidity inside the beehive to prevent the spread of varroa mites and measure the weight of the honey from the frames.

The design of automated beehive with Android technology functions as follows:  Monitor the ambient temperature and humidity inside of the beehive.  Measure the weight of frames inside beehive (load cell).

 Send measured weight and real-time temperature and humidity readings to the beekeeper through Bluetooth technology.

Project Objectives

The general objective of this project was to design a device that can monitor the temperature, humidity and the weight of the beehive to meet the requirements needed by the client in accordance with codes of ethics, engineering standards and consideration of tradeoffs based on multiple constraints such as economic constraints, sustainability and manufacturability.

Specific Objectives

 To design a prototype that could monitor the beehive temperature and humidity.

 To develop an Android application that would display the actual status and measurements of the beehive frame.

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The Client

The design project was intended for the beekeeper Dexter’s Apiary located in Parañaque. Over the years, Dexter’s Apiary has been expanding the numbers of the beehive. By the end of the year 2013, Dexter’s Apiary hopes to have at least 70 beehives to increase the production of honey.

Project Scope and Limitation

The design focused on the construction of automated beehive with Android based technology. It monitors the humidity and temperature of the beehive to inform the beekeeper through data transmission. The gathered data from the prototype would be transmitted using Bluetooth and Android based communication. On the other hand, the design’s limitations are as follows: 1) humidity and temperature outside the beehive are not covered; 2) it does not detect the number of bees; and 3) cannot extract honey from the frames. Project Development

To represent the development of the project, a flowchart was used to draw the chain of a process that connects the phase of development of the design. Figure 1.1 shows the development process in completing the project.

Figure 1.1 Project Developments Project Conceptualization Gathering Data and Requirement Identify the Problems Build Block Diagram Identify the Components Build Schematic Diagram & Simulate

Circuit Diagram

Deployment of

Design Project DebuggingTesting & Implementation Maintenance

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Figure 1.1 is an illustration of the project development process in the Design of Automated Beehive with Android technology.

Identify the Problem:

 Identifying the problem was the first step. The designers identified the problem through research, education and self-curiosity. Finding the problem would help the designers to prepare for a solution.

Gathering Data and Requirement

 Gathering of data and requirements were important since it would set as a way in providing the best solution for the identified problem. The designers needed to gather data and the necessary requirements to complete the prototype. One of the gathered data was the condition when the temperature reaches the coldest; with this condition, working bees would not be able to move and thus would die.

Project Conceptualization

 Project conceptualization was the ability to formulate any idea that occurs at the beginning of a design activity. The designers were able to formulate an initial design of the project when the scope of the project was drafted and as a result the designers came up with a prototype that could monitor the inside of the beehive.

Build Block Diagram

 Building block diagram could facilitate software development because it would provide a better understanding of what the prototype would become. The designers needed to build the block diagram for the design project that would represent the flow of the entire prototype.

Identify the Components

 Identifying the components needed for the completion of the prototype was very important not only for the sake of completing the prototype but also to seek the better quality of components to be used. After the designer built the block diagram of the project, the designers were able to identify what are the exact components that were used, and on this design one of the components that the designer used was Load cell sensor.

Build Schematic Diagram and Stimulate Circuit Diagram

 Schematic Diagram represents the elements of the system using graphic symbols. This signifies the components used and the tasks of the circuit diagram. The designers built the schematic diagram based on the circuit of the components and simulate it so that designers were sure that the circuit would simulate.

Implementation

 Implementation was necessary as it would execute the plan that was laid out upon the beginning of the prototype. Once all the necessary requirements have been met the designers would prepare for the implementation of the prototype according to the circuit created. The designers must meet the objective of the prototype for the completion of the project. With the help of the client, the prototype would be tested along with the Android application that was developed solely for the prototype.

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Testing and Debugging

 Testing and debugging the prototype could be done after all the components has properly been placed according to the right circuit diagram. The designers tested the prototype if it would simulate according to how the prototype was developed and if there were some errors, it would be debugged until it meets the requirements. The prototype would be tested to verify if it would produce accurate measurement based on the objective of the project.

Deployment of Design Project

 Deployment of the design project could be done once all the stages in developing the prototype would agree. After implementing the prototype and testing the accuracy of the measurement the designers would deploy the prototype to the client.

Maintenance

 Maintenance was offered to prevent any unnecessary difficulties, error and to maintain the ability to monitor the inside of the beehive. And lastly the designers would provide maintenance for the prototype as part of the service for the client so that if there would be any unnecessary problem met with the prototype, the designers could automatically fix the issue at hand.

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1 DESIGN INPUTS Design Constraints

In the Design of Automated Beehive with Android Technology, the consideration of multiple constraints was applied. The aspects that determined the feasibility of the system was served by these constraints. There were different kinds of constraints applicable to the creation of this design project, but the designers have selected the constraints that could affect the entire development process and these are the following:

Economic (Cost)

 The components that were used for the building of the design project were put into consideration based on the client’s requirements and the availability of the components. The designers used the components that are not harmful to the client and the environment. Considering the cost of the components, the designers used not only the affordable materials, but also the précised functionality that was needed for the design.

Manufacturability (Availability of materials)

 In developing the project, the availability of material of the design was also considered by the designers. The availability of the materials would vary the time before the start of the prototype. The designers’ main concern was if the material would be available locally or should it be shipped from other country.

Sustainability (Life Span)

 A component does not last longer than expected. There were times that components would need replacement. The designers considered the sustainability of each components used for the prototype to be completed. There were researches conducted to specify how long take a certain component would last before replacing it. This became important for the designers, should any of the component from the prototype needs to be replaced.

Design Standards

The designers used a list of standards for this project design as a basis for the circuit design and other related to the following codes and standards which are stated below:

 3-1982 - IEEE Recommended Practice in the Selection of Reference Ambient Conditions for Test Measurements of Electrical Apparatus – A standard which has the purpose of identifying and recommending a set of standard reference values for certain ambient parameters which are significant in electrical test measurements. The designers considered the standard during the measurement of temperature and humidity inside of a beehive. The standard was used in all three designs created by the designers since all designs has temperature and humidity sensor.

 ASTM E 74-02 American Society for Testing and Materials, 2002, Standard Practice of Calibration of Force – A standard for measurement instruments for verifying the force indication of testing machines. The designers used the standard for the calibration result for load cell sensor (weight sensor). All three designs used the ASTM E 74-02 standard since a weight sensor needed to be calibrated to give an accurate result of measurement.

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 IEEE standard 802.15.1 for Bluetooth Wireless Technology - The designers used this standard for the communication from the prototype to the Android device. 802.15.1 for Bluetooth Wireless Technology was under Class 2 which operates at a range of 10 meters and a maximum power of 2.5mW.

 UNIFORMAT II (E 1557) – For the entire BEES analysis, building products are defined and classified based on the ASTM standard classification for building. The UNIFORMAT II was considered during construction of beehive. The designers took in consideration the standard construction of a beehive as to avoid harming not only the environment but also the bees itself.  IEEE standards for In-System Configuration for Programmable Devices – The standard was

for providing standardized programming access and methodology for programmable integrated circuit devices. The designers used the standard when working with a programmable device such as microcontroller that holds the instruction to make the prototype function according to the objective.

Software Requirements

The software in this project was an Android Application. The knowledge applied in this application was all combinations of that software application which has been studied from Software Engineering, Java Programming and Android Programming as well as the software components needed such as Integrated Development Kit for Android Application and Microcontroller.

Knowledge in the following courses:

The designers have applied the knowledge learned from previous courses taken as listed below:

 Java Programming. Java is a computer programming language. It enables programmers to write computer instructions using English based commands, instead of having to write in numeric codes. It’s known as a “high-level” language because it can be read and written easily by humans.

 Flow code. Flow code is a type of graphical programming language for a microcontroller that uses flowcharts.

 Android programming. An Android app is a software application running on the Android platform. Because the Android platform is built for mobile devices, a typical Android app is designed for a Smartphone or a tablet PC running on the Android OS.

Hardware Requirements

The design of the project has been considered and factors that would affect the process of the development of the device.

Upon the design of this project, the designers considered the standard that would affect the process development of the device. The factors that have been considered are the knowledge, skills and materials required for the development of the design. These factors are discussed below:

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Knowledge in the following courses:

The designers have applied the knowledge learned from previous course listed below:

 Temperature and Humidity Sensor. This is a multifunctional sensor that gives you temperature and relative humidity information at the same time. It utilizes a DHT11 sensor that can meet measurement needs of general purposes. In relation with the standard the ratings of the range of the measurement is 20-90%, humidity is 5%RH Temperature 35.6 F.

 Weight. A load cells are types of sensors that can measure the weight of an object. It convert forces into electrical signals and output that electrical signals. Sensor and controller, a temperature sensor and controller is also one of the most accurate temperature sensors, its programmable controller enables you to change the conversion depending on the code that you upload. In relation with the standard power voltage of 12v, sensing area 9.53mm (0.375 in) diameter and connector 3pin Male square, the load cell was used for the prototype.

 Microcontroller. It is a microcomputer which is designed for the operation of embedded systems. It is a single chip that contains processor, a non-volatile memory for the program; volatile memory for input and output (RAM), a clock and an I/O control unit. In relation to the standard the flash 32kbytes, pin count 28 and the CPU is 8bit AVR.

 Bluetooth Shield. It is a wireless technology for data exchange over short distances (using short-wavelength radio waves. In relation with the standard the ratings of the frequency used is 2.4 GHz and the class is class 2, and the voltage used 3.1 to 4.2VDC, but it would interface directly with the UART port of any microcontroller chip running at 3.3VDC.

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CHAPTER 2. PROJECT/ SYSTEM DESIGN Input-Process-Output

The Input-Process-Output is a graphical representation of all factors/procedures in which the required inputs such as knowledge, hardware and software along with multiple constraints processed through data gathering and planning to produce the most efficient hardware and software design to meet the design objectives and arrive at the output of producing a prototype.

Figure 3.1 Input-Process-Output INPUT Requirements in: Knowledge:  Circuit Design  Electronic Circuits  Embedded Systems  Microcontroller Programming  Software Designing Hardware:  Sensors (Temperature, Humidity and Weight)  Bluetooth module  Microcontroller Software:  Android Programming  Java Programming  Flow code Multiple Constraints Engineering Standards OUTPUT  Design of Automated Beehive with Android Technology

PROCESS Data Gathering

 Monitoring the temperature and humidity inside of the beehives

 Sending message using Bluetooth technology

Design

Embedded System Circuit Designing

Testing and Evaluation of the design

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Figure 3.1 shows the requirements and how the design was processed. The inputs have all the necessary requirements before the design can be process. It is the first thing that should be prepared. The process is made up of engineering methodologies required for the production of the design project.

The inputs are made up of Knowledge, Hardware, Software, Multiple Constraints and Standard requirements. The knowledge requirement consists of the expected functionality of the design project. The hardware requirement consists of components and peripherals that would be used. The sensors would be used for monitoring the inside of the beehive, Bluetooth module would be used for communication from the device itself to any android devices that has the certain application installed on mobile devices. The microcontroller would be the main component of the system where instructions are to be executed based on the given inputs.

The software requirements consist of programming languages to be used for the microcontroller and Android Device. The Android programming and Java programming would be used for the development of Android Application while the Arduino programming would be used for microcontroller. Multiple constraints were also part of the input where it would remind the designers the different considerations to be observed such as economic, sustainability and manufacturability.

The process illustrates how the design would function based on the given inputs. The knowledge requirements consist of the detailed functionality and the engineering techniques to be used. The hardware shows how the components would be used according to the designers input.

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System Flowchart

Figure 3.2 shows the system flowchart of the automated beehive and discussed the entire system and how it works.

Figure 3.2 System Flowchart

Figure 3.2 explains how the system flows throughout the process. First, the prototype must be connected to an Android device with the application; if they are not connected, the application would terminate. However, once the prototype and the Android device are connected, the three input buttons that user could select would be available. The three input buttons consists of temperature, humidity, and weight. When one of the buttons is selected, the corresponding output would be displayed on the Android device.

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Illustrative Diagram

The Figure 3.3 shows an illustrative diagram of how each component interacts with one another.

Figure 3.3 Illustrative Diagram

Figure 3.3 is an illustration of the components and peripherals that is use for the production of the design project. It comes along with the following list of design standard that was stated previously such as 31982 -IEEE Recommended Practice in the Selection of Reference Ambient Conditions for Test Measurements of Electrical Apparatus. The purpose of the said standard is for reference value for certain ambient parameters which are significant in electrical test measure. Also IEEE standard 802.15.1 for Bluetooth Wireless Technology is use for the communication of the prototype and the android device.

Description of each component

 PIC Microcontroller: A programmable microcontroller made by Microchip Technology. It can manage the operation of embedded system used in most projects nowadays.

 Weight sensor: A transducer, which used to weighing a machine, object, etc.

 DHT11: A combination of temperature and humidity sensor, it ensures soaring reliability.

 Bluetooth Shield: A wireless hardware component was used for exchanging data in short distances.

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Hardware Design

Design 1: Using Load Cell

The first design used load cell to determine the weight of the honey from a frame inside the beehive. The temperature sensor and humidity sensor measures the temperature and humidity inside the beehive to make sure that the surroundings would not affect the colonies of the bees. The structure measured by the device was in accordance with the standard for measuring devices.

All the output values from the sensors were directed to the microcontroller which processed the values taken before transmitting it to another device by the use of Bluetooth shield. The Bluetooth shield was used for transmission of data towards Android Device. The Android device presents the processed data.

The designers considered the standard for load cell that was used in designing a prototype. According to ESTD 1950 standard, load cell is a single point platform and a strain gauge based low profile bending beam load cell and is suitable for single point platform scale having platform ranging up to 1000x1000mm.The designers also consider the IEEE standard of 3-1982 - IEEE Recommended Practice in the Selection of Reference Ambient Conditions for Test Measurements of Electrical Apparatus - In general, test results and the performance of electrical apparatus are significantly influenced by variations in such parameters as temperature, barometric pressure and humidity. The purpose of this IEEE recommended practice is to identify and recommend a set of standard reference values for certain ambient parameters which are significant in electrical test measurements.

Sustainability.

The sustainability of the load cell depends on the performance, sensitivity and the temperature. According to Strain Measurement, load cell enables a long term stability of better that 0.1% per year. Although the components sustainability would depend on how long it would be used and where would be used.

Manufacturability.

The manufacturability of the components would be really beneficial for the designers because the load cell can be purchased within the country itself and you do not need to order it from other country.

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Economics.

The designers took consideration of the cost of the materials to be used in this design. As stated in Table 3-1 below the list of costing that would be used in designing an automated beehive using a load cell. As stated below the load cell is an affordable component.

Table 3-1 Cost of Materials of Design 1 Materials Costs Atmega328 PHP 250.00 Load cell PHP 820.00 DHT11 PHP 105.00 Bluetooth shield PHP 935.00 Ceramic Capacitors PHP 12.00 Resistors PHP 2.00 Crystal Oscillator PHP 20.00 Printed Circuit Board PHP 510.00 Rectifier Diode PHP 7.00 Stackable Female Header PHP 16.00 UART PHP 15.00 Lead PHP 30.00 LED PHP 2.00 Transistor PHP 60.00 Ferric Chloride PHP 22.00 Beehive PHP 2700.00 Total Cost: PHP 5,506.00

Table 3-1 shows the different components and total cost of the materials of design 1. The designers used ATmega328 that cost Php 250.00, a load cell was also used for the weight measurement that cost Php 820.00, a DHT11 sensor for the temperature and humidity measurement that cost Php 105.00. The designers also used Bluetooth shield for the wireless transmission of data from the prototype to android device and it cost Php 935.00, a ceramic capacitors that cost Php 12.00, a resistor cost Php 2.00, a crystal oscillator that cost Php 20.00. A printed circuit board which was a double sided board was used to etch the home made circuit that cost Php 510.00, a rectifier and a stackable female header for connector that each cost Php 7.00 and Php 16.00. UART was used that cost Php 15.00, the lead was used with soldering iron to connect the component to the printed circuit board and it cost Php 30.00. LED, transistor, Ferric chloride and lastly the Beehive itself was also used for the completion of design 1 and each component cost Php 2.00, Php 60.00, Php 22.00 and Php 2700.00.

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Prototype Design

The Figure 3.4(a) illustrates the design of Automated beehive, and Figure 3.4 (b) illustrates design 1 using load cell sensor.

The designers constructed a Design of Automated Beehive with Android Technology using load cell. Figure 3.4 (a) show the structure of the beehive using woods while the sensor that have been used in the design 1 is a load cell as shown in Figure 3.4 (b) load cell is attached to the plywood and also the DHT11 temperature and humidity sensor. The standard used for this design was ASTM E 74-02 American Society for Testing and Materials, 2002; Standard Practice of Calibration of Force this standard was used to specify procedures for the calibration of force-measuring instruments such as balances and small platform scales.

Figure 3.4 (b) Load cell sensor Figure 3.4 (a) Automated Beehive

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Circuit Diagram

Figure 3.5 shows the schematic of the electronic components of the Automated Beehive with Android Technology using load cell.

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Figure 3.5 Schematic Design of Automated Beehive with Android Technology using Load cell sensor Computation for Circuit Diagram:

The formula below can be used to get the resistance that the microcontroller is releasing during the process. In this formula, the designers used the standard voltage and current needed for the microcontroller.

Equation 3.1 Ohm’s Law

_{V = IR}

Where: V = Voltage I = Current

Ohm’s Law Electronics, Devices and

Circuits BY: Robert L. Boylestad

In R. B. Nashelsky, Electronics,

Devices and Circuits Theory.

Given: V = 3.3 V I = 200mA R = ?

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The standard voltage of a microcontroller such as ATmega328 was 3.3V and a current of 200mA. By using the given data, resistance could be calculated by using Ohm’s law.

V =IR

3.3 V =500 mA x R

R= 3.3 V 200 mA R=16.5 Ω

The value of 16.5Ω defines the resistance needed by the microcontroller during the process. Therefore, the resistance calculated using Ohm’s Law represents the value that coming in and out of the microcontroller. By knowing the formula of Ohm’s Law, it would give the student the right voltage, resistance and current to be used to avoid short circuit, over voltage and etc.

Specifications and Cost of Materials

The total cost of materials in this design as stated in Table 3-1, is Php 5506.00

Table 3-2 shows the specification of materials for design 1 which provides insight on what particular needs of the design that the materials should satisfy in order to achieve the designers’ objectives.

Table 3-2 Design 1 Specification of Materials of Design 1

Materials Specifications

Atmega328 Flash 32kbytes

Pin count 28 CPU 8 bit AVR

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Load cell Thickness 0.203 mm (0.008 in.) Width 14 mm (0.55 in.)

Sensing Area, 9.53 mm (0.375 in.) diameter

Connector 3-pin Male Square Pin (center pin is inactive)

DHT11 Size 22.0mm X 20.5mm X

1.6mm

Voltage 3.3 or 5V DC Resolution 8-bit temperature Bluetooth shield Sensitivity: -80dBm at 0.1%

BER

Voltage: 3.3V

Host Interface: USB/UART Flash memory size: 8Mbit

Ceramic Capacitors 100nf, 22pf

Resistors 1.5KΩ, 330Ω, 10KΩ

Crystal Oscillator 16MHz

Printed Circuit Board Pre-sensitized

Rectifier Diode 1 & 4001

Stackable Female Header

8 pins, 6 pins

UART Type B

Lead 0.3mm

LED Red, Green 5mm

Transistor RT9163/ 3.3V regulator

Ferric Chloride

Beehive 8 frames, top lid

Table 3-2 provides a specification regarding the components that the designers used for the first design such as ATmega328, load cell, DHT11 sensor, Bluetooth shield, ceramic capacitors, resistors, crystal oscillator, printed circuit board, rectifier diode, stackable female header, UART, Lead, LED, transistor, ferric chloride and the Beehive.

The economic constraint with respect to the materials that is being used for the design project by using weight sensor (load cell) is just right. The components that are used for the building of the design project are put into consideration based on the client’s requirements and the availability of the components. It is also not harmful to the client and the environment. Considering the cost, the components is affordable and its function properly. The sustainability constraint depends on the user or it on how you actually use the materials. While the manufacturability of the materials is available inside Philippines and there is no need to order outside the country for the materials that is shown.

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Design 2: Using Torque Sensor

Figure 3-6 shows the structured of the Automated Beehive with Android Technology using a torque sensor as measuring device for the weight. Torque sensor is a device that was used to measure not only the rotation of a system, but also measured the applied force on the object.

The design was also composed of different sensors such as temperature sensor to measure the temperature inside surroundings of the beehive, a humidity sensor to measure moisture within the beehive and lastly the torque sensor to measure the weight of the beehive.

The designers consider the standard for torque sensor that needs to be used in designing a prototype. The torque is a transducer that converts mechanical input to an electrical output. The designers also consider the standard ISO/IEC 17025:2005(en) General requirements for the competence of testing and calibration laboratories The designers also considered the standard of 3-1982 - IEEE Recommended Practice in the Selection of Reference Ambient Conditions for Test Measurements of Electrical Apparatus - In general, test results and the performance of electrical apparatus are significantly influenced by variations in such parameters as temperature, barometric pressure and humidity. The purpose of this IEEE recommended practice is to identify and recommend a set of standard reference values for certain ambient parameters which are significant in electrical test measurements.

Sustainability.

The sustainability of the torque sensor according to HBM Test and Measurement guarantees accurate results over the wide measuring frequency range of 0 Hz to 6,000 Hz, even up to physical limits. Its sustainability would depend on the location and the manner the components are used. When a component was used for heavy mechanism, there would be a possibility that the component may need a new replacement.

The manufacturability of the prototype would be restrained by the availability of the components as the designers need to purchase some components from abroad. It takes one to two months to purchase the torque sensor.

Economics.

The designers took consideration of the cost of the materials to be used in Design 2. As stated in Table 3-3 below the list of costing that would be used in designing an automated beehive using a Torque sensor. As stated below torque sensor has the highest price but still economically friendly.

Table 3-3 Cost of Materials using Torque Sensor

Materials Costs

Atmega328 PHP 250.00

Torque Sensor PHP 1906.00

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Bluetooth shield PHP 935.00

Ceramic Capacitors PHP 12.00

Resistors PHP 2.00

Crystal Oscillator PHP 20.00

Printed Circuit Board PHP 510.00

Rectifier Diode PHP 7.00

Stackable Female Header PHP 16.00

UART PHP 15.00 Lead PHP 30.00 LED PHP 2.00 Transistor PHP 60.00 Ferric Chloride PHP 22.00 Beehive PHP 2700.00 Total: PHP 6,562.00

Table 3-3 shows the components and total .cost of the materials of design 2. The difference between table 3-1 and table 3-3 is that for design 2, the designers’ would use torque sensor instead of load cell for measuring of weight. The cost of the torque sensor is Php1906.00.

Project Design

Figure 3.6(a) illustrates the design of automated beehive, and Figure 3.6(b) illustrates the Design 2 using torque sensor.

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The designers constructed a Design of Automated beehive with Android Technology using a torque sensor. Figure 3.6 (a) show the structure of the beehive using woods while the sensor that have been used in the design 2 is a torque sensor as shown in Figure 3.6 (b). Torque sensor is attached to the plywood and also the DHT11 temperature and humidity sensor. The standard used for this design was ASTM E 74-02 American Society for Testing and Materials, 2002; Standard Practice of Calibration of Force this standard was used to specify procedures for the calibration of force-measuring instruments such as balances and small platform scales and also the Standard ISO/IEC 17025:2005(en) General Requirements for the competence of testing and calibration laboratories.

Circuit Diagram

Figure 3.7 shows the schematic of the electronic components of the Automated Beehive with Android Technology using Torque Sensors.

Figure 3.6(b) Torque Sensor Figure 3.6(a) Automated Beehive Design 2

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Figure 3.7 Schematic Design of Automated Beehive with Android Technology using Torque sensor Computation for Circuit Diagram:

22 Ohm’s Law

V = IR

Where: V = Voltage Ohm’s Law Electronics, Devices and

Circuits

Given: V = 3.3 V I = 200mA R = ?

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Equation 3.1

V =IR

3.3 V =500 mA x R

R= 3.3 V 200 mA R=16.5 Ω

The total cost of this material as shown in Table 3-3, is Php 6562.00.

Specification and costing of material for Design 2 provides information with regards to the components that the designers used for the completion of Design 2. Table 3-4 shows the detailed tabulation of each component’s specifications.

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Table 3-4 Design 2 Specification and Cost of Materials using Torque Sensor

Torque Sensor Measure the rotation in a

system

Measure the applied force in an object

DHT11 Size 22.0mm x 20.5mm x

1.6mm

BER

Voltage: 3.3V

Stackable Female Header 8 pins, 6 pins

UART Type B

Lead 0.3mm

Ferric Chloride

Table 3-4 shows the components specification of each material which would be used for the completion of design 2. It could be seen here the different sensor that was used for measuring the weight of honeys inside the beehive.

Design 3: Using Touch Sensor

Touch sensor is a type of device that can measure the weight of an object just by applying a force on it. By using this device the desired weight for the honeys from the frame can be determined.

The design was also composed of different sensors such as temperature sensor to measure the temperature inside surroundings of the beehive, a humidity sensor to measure moisture within the beehive and lastly the torque sensor to measure the weight of the beehive.

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The designers consider the standard for touch sensor; the touch interface allows for quick and easy menu driven set up of all parameters including auto zero, pressure ranges, output ranges, format of pressure, percent output or it could also use the interface to create custom ranges by adjusting the upper and lower pressure. The designers also consider the standard of 3-1982 - IEEE Recommended Practice in the Selection of Reference Ambient Conditions for Test Measurements of Electrical Apparatus - In general, test results and the performance of electrical apparatus are significantly influenced by variations in such parameters as temperature, barometric pressure and humidity. The purpose of this IEEE recommended practice is to identify and recommend a set of standard reference values for certain ambient parameters which are significant in electrical test measurements.

Sustainability.

Touch sensor is a sensitive component since it could detect object easily. The sustainability of the component depends on the way it’s being used. As what is stated to an article of Embedded Computing Design, the performance, accuracy, and reliability of the touch sensor depends on the noise generated from a display such as LCD. Thus, reliability, performance, and the quality of user experience are significantly affected by how the system addresses noise.

The manufacturability of the prototype would be restrained by the availability of the components as the designers need to purchase some components from abroad. It takes one to two months to purchase the touch sensor.

Economics.

The designers took consideration of the cost of the materials to be used in design 3. As stated in Table 3-5 below the list of costing that would be used in designing an automated beehive using a touch sensor. As stated below, the touch sensor which the price is a little bit higher, but still there is a lot company using a touch sensor because of his economically price.

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Table 3-5 shows the cost of each component for design 3. From the table, it could be seen that a different sensor for measuring the weight of the honey inside the beehive would be used for the measurement which was the touch sensor.

Project Design

Figure 3.8(a) illustrates the design of Automated beehive, and Figure 3.8 (b) illustrates the Design 2 using touch sensor. Materials Costs Atmega328 PHP 250.00 Touch Sensor PHP 357.00 DHT11 PHP 105.00 Bluetooth shield PHP 935.00 Ceramic Capacitors PHP 12.00 Resistors PHP 2.00 Crystal Oscillator PHP 20.00 Printed Circuit Board PHP 510.00 Rectifier Diode PHP 7.00 Stackable Female Header PHP 16.00 UART PHP 15.00 Lead PHP 30.00 LED PHP 2.00 Transistor PHP 60.00 Ferric Chloride PHP 22.00 Beehive PHP 2700.00 Total: PHP 5,013.00

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The designers constructed a Design of Automated beehive with Android Technology using torque sensor. Figure 3.8 (a) show the structure of the beehive using woods while the sensor that have been used in the design 2 was a torque sensor as shown in Figure 3.8 (b). Torque sensor is attached to the plywood and also the DHT11 temperature and humidity sensor. The standard used for this design was ASTM E 74-02 American Society for Testing and Materials, 2002; Standard Practice of Calibration of Force this standard was used to specify procedures for the calibration of force-measuring instruments such as balances and small platform scales, and also the standard used for this Figure was UNIFORMAT II (E 1557) which was responsible for the well-being of the bees upon constructing of beehive.

Circuit Diagram

Figure 3.9 shows the schematic of the electronic components of the Automated Beehive with Android Technology using Touch Sensors.

Figure 3.8.(b) Touch Sensor Figure 3.8.(a) Automated Beehive Design 3

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Figure 3.9 Schematic Design of Automated Beehive with Android Technology using Touch sensor Computation for Circuit Diagram:

28 Ohm’s Law

V = IR

Where: V = Voltage Ohm’s Law Electronics, Devices and

Circuits

Given: V = 3.3 V I = 200mA R = ?

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Equation 3.1

V =IR

3.3 V =500 mA x R

R= 3.3 V 200 mA R=16.5 Ω

As shown in Table 3-5, the total cost for the design 3 is Php 5013.00

Specification and cost of materials for design 3 provides information with regards to the components needed by the designers to complete the prototype. Table 3-6 shows the detailed specification of each component.

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Table 3-6 Design 3 Specification and Cost of Materials using Touch Sensor

Touch Sensor Measure the applied force in an

object

DHT11 Size 22.0mm x 20.5mm x

1.6mm

BER

Voltage: 3.3V

Stackable Female Header 8 pins, 6 pins

UART Type B

Lead 0.3mm

Ferric Chloride

The economic constraints with respect to the materials that is being used for the design project by using Touch sensor is just right because the components that were used also meets the client’s requirements, the same with Weight Sensor and Torque sensor. It is also not harmful to the client and the environment. Considering the cost, the component is more affordable compare to weight sensor and torque sensor and still functioning properly. The sustainability constraints depend on how you use it or how you use it. While the manufacturability of the materials is available inside Philippines and it can also be orders outside the country.

Software Design

Graphical User Interface Design

Figure 3.10 shows the graphical user interface (GUI) was designed to be pleasing to the eyes of our client in which we used bees and honey’s to represent it. The design has different features in which our client would check directly through their android devices the humidity, temperature and weight of the honey.

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Figure 3.10 Graphical User Interface Design

In Figure 3.11, it shows the second screen of the Android Application Software that displays the real-time measurement of the sensors such as DHT11 Temperature & Humidity as well as weight sensor. Each button represents different sensors. The close button is used to terminate/close the application; the back button is used to return to the main screen while the open button is to connect the Android Application to the Bluetooth device attached to the circuit board.

Figure 3.11 Graphical User Interface Design Phases 2 Software Development Life Cycle

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Figure 3.12 Software Development Life Cycles

Figure 3.12 shows the flow process in developing the software in different series. Thus we consider the different standard and constraints for this development like the cost and the availability of the parts that is needed, also the standard of each component.

The waterfall model is a sequential process, regularly used in software development processes, in which development was seen as flowing progressively down. In our Waterfall Model we have six phases; Engineering Requirements, Analysis, Design, Coding, Testing and Operational.

First Phase: Engineering Requirements

The first phase involves understanding and functionality that is needed for the design and its purpose. In this phase the designer also considers the client requirements.

Second Phase: Analysis

The second phase involves the software needed for proper completion of the project is analyzed. In this phase the designer should decide what programming language should be used for the designing software. Third Phase: Design

The third phase involves the design of the software. In this phase the designer should be ready to use for the next phase.

Fourth Phase: Coding

The fourth phase involves the actual coding of the program created from the third phase. In this phase the designers finalizes the right programming language to be used.

Fifth Phase: Testing

The fifth phase involves the testing of the program. In this phase the coding of the program was complete from the previous phase. The testing of the written codes is occurring. In this phase it ensures that the client interested and satisfied with the finish software design. And if there is a problem with the codes the designers need to go back to the design phase and the changes are implemented.

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The sixth phase involves the operational of the program. In this phase the designers completely finished the software and it shows the fully operational software that is used on the project.

System Algorithm

Table 3-7 shows how the android application was design to operate using android technology. Table 3-7 System Algorithms for the Design of Automated Beehive with Android Technology

Initialization Input Process Output

Initialize Temp = 0 Android command = Display Temperature Compute the Temperature

Display the Temperature to the LCD Initialize Humidity = 0 Android command = Display Humidity Compute the Humidity

Display the Humidity to the LCD Initialize Weight = 0 Android command = Display Weight Compute the Weight

Display the Weight to the LCD

Table 3-7 shows the algorithm in which the design was being operated by the designers. Initialization was performed to find the initial value of an object or device that was used for the design. The input table refers to the value that was inputted / processed during the production of the design. The process table expresses how the algorithm works in which it depends on the designers’ inputted value. The output table shows the final product of the process where the data gathered was sent to the Android device.

Dataflow Diagram

Figure 3.13 shows the dataflow diagram of how the design would process from hardware to software

Command Temperature Humidity Weight

Figure 3.13 Data Flow Diagram

This dataflow diagram was a representation of the design in which it shows how it would work. The design needs to undergo many actions as it process through the system. First, the user would open the application and connect it to the prototype with the use of Bluetooth technology. When the android device has been connected, the user could select what input to measure. After the user select the input it would directly communicate to the microcontroller and display the measured data on the android devices.

USER

Android

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CHAPTER 3. DESIGN TRADE-OFFS Design Trade-offs

Starting up the design trade-offs, the designers consider the functionality that can satisfy the economic, sustainability and manufacturability constraints. The designers select the type of weight sensor to be used that give the appropriate functionality for the project design.

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In the design, the use of the right weight sensor was placed under consideration. The trade-offs provide the comparison of each component to be used in the circuit. Load cell was used to identify the weight of the object.

Based on the constraints articulated previously, the various decision criteria were derived. Using the model on trade-off strategies in engineering design presented by Otto and Antonsson (1991), the importance of each criterion (on a scale of 0 to 5, 5 with the highest importance was assigned and each design technology’s ability to satisfy the criterion (on a scale from -5 to 5, 5 with the highest ability to satisfy the criterion) was likewise tabulated.

Below is the computation of ranking for ability to satisfy criterion of materials:

%difference=(Higher Value−Lower Value)

Higher Value Equation 4.1

Subordinate Rank=Governing Rank−(%Difference ) x 10 Equation 4.2

The governing rank was the subjective option of the designers where in the value for the criterion’s importance and its ability to satisfy the criterion would be chosen by the designers. Unlike subordinate ranking, governing rank does not require any calculating. The table below shows the sample of trade-offs of the sensors used in the designed circuit.

Three schematic designs have been considered for the trade-offs to be used. The three schematic designs have a different capabilities of weight sensor used for the design of Automated beehive with Android Technology. Design 1 used Load cell, Design 2 used torque sensor and Design 3 used touch sensor. In order to find the best component, it was rated using the designers’ criterion. Each design has been discussed previously.

After considering the design constraints, the designers came up with the initial rankings on the Design of Automated Beehive with Android Technology. Table 4-1 shows Designers raw ranking based on sustainability, manufacturability, and cost constraints.

Table 4-1 Designer Tabulation Form

Decision Criteria Criterion’s Importance

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Design 1

(Load Cell) Design 2(Torque Sensor) Design 3(Touch Sensor)

Economics (Cost) 5 4 2 5

Manufacturability

(Availability) 3 5 3 4

Sustainability (Life Span) 4 4 5 3

Overall Rank 51 39 49

Reference: (Otto, 1991)

http://www.design.caltech.edu/Research/Publications/90e.pdf on March 11, 2013.

In determining the trade-offs for the designs, the designers assigned respective importance values for each criterion shown in Table 4-1. The economic constraints or the cost of the device was given importance by ranking it into the highest value, which were given a five since the device must be low-cost and was available to manufacture with less expenses. The designers had also taken into consideration the importance of sustainability or the life span of the materials used and it were considered to be the second on the highest value such as four since the materials has its own capability to stay longer. The manufacturability or the availability of materials used was considered to be the third. It doesn’t really matter whether the materials were bought locally or internationally, yet important to consider because it deals with the time of labor.

TRADE-OFF #1: Economics

Initial Cost Estimate for Design of Automated Beehive with Android Technology

Table 4-2 shows the over-all cost of the Design 1, 2 and 3. The ranking, stated in the tradeoff table would be based on the formula that is computed. The total cost for each specific component to be used was tabulated previously.

Table 4-2 Initial Cost of each component

Design Category Total

Design 1 PHP 5,506.00

Table 4-2 represents the price of the device in the industry and its quantities when manufactured. The equations mentioned above were considered to calculate for the values of the ability to satisfy the criterion. Computation for Trade-Offs #1:

To compute the value of the ability to satisfy the criterion the designers need to determine the value of the subordinate rank. As for the Design 1 (LOAD CELL):

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To get the percent difference, subtract the value of the first design that consists of Load cell to the value of the third design that consists of Touch sensor and divide it into the value of Load cell.

%difference=5506−5013 (5506 )

%difference=0.089

Subordinate Rank=Governing Rank−(%difference) x 10 Subordinate Rank=5−(0.089) x 10

Subordinate Rank=−3.95

Figure 4.1 Subordinate ranking of Load cell in economic cost

Figure 4.1 represents the subordinate ranking of the device, load cell, to satisfy the criterion from Table 4-1. The value calculated signifies the importance of a device in a design project. As the Figure shows, load cell has the significance of -3.95 which means that it was one of the main components of the prototype.

The value calculated from the subordinate rank would be tailing in the Table 4-1. To calculate the value of the criterion of Design 2 (Torque Sensor), use equations 2.1 and 2.2:

%difference=Torque Sensor−Load cell

(Torque Sensor)

%difference=6562−5506 (6562)

%difference=0.16

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Subordinate Rank=3.4 ≈ 3

Figure 4.2 Subordinate ranking of Torque sensor in economic cost

Figure 4.2 represents the similarity to the Load cell, Torque sensor criterion was tailed under Table 3-2. This shows that Load cell has a higher criterion that it acquires during the calculations. This was due to the affordability of the device in the market. Considering the value of the Figure 4-1, it shows that in Figure 4-2, load cell has a higher importance than torque sensor having a value of 3.4 for the economic cost criterion. TRADE-OFF #2: Manufacturability

Table 4-3 shows the estimated number of days in order to acquire the sensors used for the three designs. The table is used as the basis of the ranking on Trade-offs in accordance with the computations.

Table 4-3 Availability of the Materials

Design Sensors Days(s) to Acquire

Design 1 Load cell 1

Design 2 Torque sensor 7

Design 3 Touch sensor 5

As stated on the previous chapter, manufacturability was one of the most important design constraints because some of the components may not be available within the country and thus needed to be bought outside of the country. The estimated days to acquire the desired component are 1 day since the component is available within the country.

Computation for Trade-Offs #2:

Touch sensor has similarities to Torque sensor when it comes to the availability of the materials. Though the touch sensor can also be found outside the country, torque sensor is indeed hard to find compared to touch sensor. Using the equations 4.1 and 4.2, the value of manufacturability criterion can be calculated.

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%difference=(7−1) (7 )

%difference=0.86

Subordinate Rank=−5.6 ≈−5

Figure 4.3 Subordinate ranking of Load cell sensor in manufacturability

Figure 4.3 shows the computed value acquired for the manufacturability of the Load cell sensor considering the time it takes to assemble the device on the prototype. From the calculated value, -1.30 represents the ratio of availability of the material to be used to complete the prototype.

Using the same equations, the value of the Touch Sensor can be calculated as follows:

%difference=(Touchsensor availability−Load cell availability) (Touch sensor availability )

%difference=(5−1) (5 )

%difference=0.8

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Figure 4.4 Subordinate ranking of Touch sensor in manufacturability

Using the same equation used to compute the value of manufacturability on load cell, Figure 4-4 represents the computed value for the touch sensor. Considering the value of 5, it represents the ratio of the availability of the device in the market.

TRADE-OFF #3: Sustainability

Table 4-4 shows the life span or sustainability of each component depending on their quality. The designers considered another method of computing the sustainability criterion. The criteria were ranked from 1 to 3 wherein 3 is the highest which means it was the best. 2 mean better and 1 means good. The ranking was based upon the sustainability of the materials that is being used on the design prototype. The basis of these criteria was taken based on the components accuracy, sensitivity, stability, time it would response, linearity and their life span.

Table 4-4 Sustainability of components Criteria Design 1 (Load Cell) Design 2 (Torque

Sensor) Design 3 (Touch Sensor) Accuracy 3 1 2 Sensitivity 2 1 3 Stability 3 2 1 Life Span 2 3 1

Fast Response Time 3 1 2

Linearity 2 3 1

Total 15 11 10

The designers chose the Load cell design to obtain the highest rank due to its availability and sustainability to be used in the prototype. To calculate the values of the ability to satisfy the sustainability criterion, it was required to determine the value of the subordinate rank.

Computation for Trade-Offs #3:

By using the same equations from before equations 2.1 and 2.2, the designers were able to compute the value needed for the said criterion.

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%difference=(Higher value−Lower value) (higher value)

%difference=(15−10) (15 ) %difference=0.33

Subordinate Rank=0.70 ≈ 0

Figure 4.5 Subordinate ranking of Load cell based on sustainability

Figure 4.5 shows the acquired values for the subordinate rank for load cell depending on the designers chosen device to work on the prototype. The calculated value of 0.70 represents the sustainability of the device according to the designers.

The same equations would be used to compute the said criterion for Touch sensor.

%difference=(Higher value−Lower value) (higher value)

%difference=(15−10) (15 ) %difference=0.33