Palletizing Robot

The boiler weighs a total of 35 kg including box when finished. The requirements for the robot are thus:

- Ability to work close to people without harming them; - Possibility to load 35 kg;

- Reach of at least one meter.

The robot that best suits these requirements is the FANUC CR-35iA (Figure 5-9). This robot can carry up to 990 kg and has a reach of 1813 mm. The price of this robot is €75,000 Euros including vacuum gripper (Price data was gathered from the Bosch OneNote on Robots). The time that would be saved by automation of this step is the time for stepping to the vacuum hoist and using the vacuum hoist to lift the boiler to the pallet. This time amounts to

34.7 seconds. This time is only saved if the employee is able to perform other actions during this time or if the cycle time can be reduced.

Result of Line Balancing Application

The Line Balancing Application is used to see how the line could be rebalanced if the 34.7 seconds are not performed by the employee, but by a machine. The solution of this SALBP optimization is included in Appendix 4. A summary of the objective functions is provided in Table 5-14. We also examine the option of the combined implementation of the palletizing robot, improved part allocation in the racks and the partial removal of the kitting area. The result of the line balancing application for this instance is also included in the table and Appendix 4.

Palletizing robot Baseline

Near-optimal SALBP solution for current situation with implementation of a

palletizing robot

Cycle Time 219 seconds 226 seconds

Number of Workstations 11 11

Line Balancing Efficiency 97.3% 95.2%

Smoothness Index 30.6 52.6

Near-optimal SALBP solution for current situation with implementation of a palletizing robot, 5S and partial removal

of kitting area.

Cycle Time 216 seconds 226 seconds

Number of Workstations 11 11

Line Balancing Efficiency 97.4% 95.2%

Smoothness Index 22.4 52.6

Table 5-14 SALBP solution with robotic palletizer

It should be mentioned that removal of the test heads of the final test is done on a different workstation than attachment of the test heads. However, the entire process cycle of the test is finished on the workstation where the test heads are attached. Therefore, the solution is seen as a possible task division.

Economics

If one accounts for the production numbers of the upcoming years, one can calculate the time savings of having the lower cycle time of 219 compared to the current cycle time of 232. As employee costs are confidential, the calculation has been left out. For the power costs the fact sheet of the Fanuc was consulted. The robot uses an average of 1 kW and the cost of a kW is estimated at € 0.21 (Consumentenbond, 2018). However, as the current vacuum lifter also uses energy, it is assumed that the energy use is comparable and the operating costs are left out of consideration as a consequence.

56 The economic evaluation of the robot investment is presented in Table 5-15. The economic evaluation of the combination of investments is presented in Table 5-16.

Year Initial Investment (€) Maintenance cost (€) Reconfigura tion cost (€) Cycle Time Savings (€) Yearly Cash Flow (€) Cumulative Cash Flow (€) NPV (€) 1 75000 7500 2000 36129 -48371 -48371 -48371 2 7650 34372 26722 -21650 -23856 3 7803 33336 25533 3883 -2366 4 7959 31336 23377 27260 15686

Table 5-15 Economic Evaluation of Palletizing Robot

The pay-back period of this investment without taking into account the time-value of money is 2 years and 310 days. When taking into account the time-value of money the pay-back period is 3 years and 121 days. However, the economic analysis does not consider the cost for installation of the robot, the need for sensors, and a more structured supply of boilers to the palletizing robot. Inclusion of these aspects would increase the initial investment significantly. This means that the pay-back period is also longer and that the required pay-back period of 3 years is very difficult to attain. If the robot can serve both TrendLine production lines the investment will most likely be interesting as the labour savings can be doubled without doubling the investment and maintenance costs.

Year Initial Investment (€) Maintenanc e cost (€) Reconfigura tion cost (€) Labor Savings (€) Cycle Time Savings (€) Yearly Cash Flow (€) Cumulati ve Cash Flow (€) NPV (€) 1 122500 12250 6000 45624 44466 -95126 -95126 -95126 2 0 12495 0 46536 42303 34041 -61085 -63895 3 0 12745 0 47467 41029 34722 -26362 -34670 4 0 13000 0 48417 38568 35417 9055 -7322 5 0 13260 0 49385 36233 36125 45180 18270

Table 5-16 Economic Evaluation of Combination of Investments

This table shows that the combination of the palletizing robot and the partial removal of the kitting area performs worse than implementation of either one of the two investments. The extra cycle time saving of 3 seconds does not make up for the investment of both systems.

Ergonomics

With regard to ergonomics, this palletizing robot can greatly improve the ergonomic score at Workstation 11. Currently, the employee uses a vacuum gripper to move the finished boilers from the roller band to the pallet. This vacuum gripper does the carrying, but the gripper has to be steered and this is relatively difficult. Moreover, less walking is needed to perform all operations. The ergonomic change is classified as better (+).

5.6

Kanban

Whenever a production employee finds itself an empty bin, the bin is removed from the rack and the Kanban card attached to the bin is put in a fixed location. The employees from logistics that supply the production line with a milk-run trolley look for these cards and scan them whenever they encounter one. A problem with this system is the delay between the time the production employee notices the empty bin and the time the logistics employee drives by the corresponding Kanban card. Logistics is

57 aware of this problem and researched whether it would be beneficial to have the production employees scan the Kanban cards immediately when a bin is empty. The research found that around 0.1 FTE is used for scanning the Kanban cards during the milk-run delivery round. If scanning is eliminated, the 0.1 FTE can be used more efficiently elsewhere and is saved. An additional 4,000 Euros is wasted on work at Logistics that relates to lost Kanban cards. Moreover, the replenishment time of the milk-run would reduce from 40 to 25 minutes which could reduce the inventory on the production line, if it were not for having two bins at most locations already. The change would not invoke any changes for the production employees as scanning would take the same time as placement of the Kanban card. All in all, the logistics departments concluded that the project was too expensive for the benefits it would gain.

A meeting with the researcher of Logistics evidenced that boiler losses due to late supply and lost Kanban cards were not taken into account as benefits. During the meeting, it was decided that looking into these figures would be part of this research. For this purpose, an overview of the boiler losses and causes of all production lines was obtained from the head of the MFO department. Analysis found that around 6,700 Euros was lost this year due to bad performance of the Kanban system.

Desktop research found an automated Kanban system that works with sensors. The biggest advantage of this system is transparency. At the moment, it is not clear whether the production or logistics employee is responsible for too late supply or a lost Kanban card. This causes finger-pointing between the two departments. An automated system that senses that only one bin is left and automatically signals the logistics department, not only removes the time delay, but also makes the process transparent. Moreover, the system prioritizes bin replenishments and stores information on all parts. This information can be used to optimize part storage.

Economics

The supplying company was invited for a visit to obtain cost information. Implementation of the system for the entire TrendLine A production line alone with approximately 150 part locations would cost 28,236 Euros whereas the cost of the lost boilers on this production line is only 1,679.36 Euros. However, the supplier suggested to use the system only for high-value items or parts for which problems occur. The part numbers for which the losses occurred amount to approximately 100 part locations. The required investment for having the system on these part locations is 19,276 Euros. The Logistical savings are not taken into account, as only a small part of the products is replenished automatically.

Installation of the system is not done by the supplier and requires time. This time is translated to costs and taken into account as installation costs. To account for inflation, the boiler savings are incremented with 2% every year. The interest rate used within Bosch is obtained from the financial controller. The resulting NPV calculation is presented in Table 5-17.

Year Initial Investment (€) Installation costs Internal (€) Boiler Savings converted to (€) Yearly Cash Flow (€) Cumulative Cash Flow (€) NPV (€) 1 19276 4000 6677 -16599 -16599 -16599 2 6811 6811 -9788 -10350 3 6947 6947 -2841 -4503 4 7086 7086 4245 969

58 The pay-back period of the investment is 3 years and 147 days without consideration of the time-value of money and 3 years and 316 days taking into account the time-value of money. However, there are also some soft wins that are highly beneficial to the processes:

• No finger-pointing between logistics and production, the system is transparent and stores out- of-stock information.

• Information is stored on all products. This data can be used to optimize part storage in the warehouse and reduce or enlarge bin sizes where possible.

• Time delay between the empty bin and signal of an empty bin to logistics is removed.

Moreover, the system is very flexible and easy to extend to other parts. Whenever another product is found to result in boiler losses, the technical team can reallocate the sensors to another part location. Extension sets can be bought in multiples of 25 or 50. All in all, it is very important to consider these soft-wins when thinking about rejecting the investment due to the somewhat longer pay-back period.

Ergonomics

In terms of ergonomics, this change would be of no harm nor added value. The employees still have to manually remove the empty bins and place them in the empty bin location. The only benefit it might have is the reduced number of times a logistics employee has to get of his milk-run trolley to scan cards. However, as this is done while the production lines are supplied, the occurrence of extra stepping off of the milk-run trolley is small. The ergonomic change is classified as indifferent (0).

5.7

Conclusion

This chapter discussed a lot of options for productivity improvement. Some options were discarded after consultation with external companies or employees of the TEF department. Other options were analysed more in-depth for the monetary and ergonomic implications.

The final selection of thoroughly investigated options are: - Use of a line balancing application;

- Partial removal of the kitting area by moving parts to the production line; - Implementation of a palletizing robot;

- Implementation of an automated Kanban system.

The creation and use of a Line Balancing Application were discussed. Usage of this Line Balancing Application for the current task division found a possible decrease of 6 seconds on the current cycle time of 232 seconds. Subsequently, the application was also used for proposed options that affect the operations in the production line. The results of these analyses are summarized in Table 5-18.

Optimization problem Cycle Time (sec) # of Workstations LBE (%)

Current situation (CS) 232 11 91.4

Line balance CS 226 11 95.2

Line balance CS + partial removal kitting area 226 11 94.5

Line balance future situation with test of 188 sec. (FS)

219 11 97.8

Line balance FS + partial removal kitting area 216 11 98.0

Line balance CS + palletizing robot 219 11 97.3

59 One can see that the cycle time and line balancing efficiency improve substantially in most of the cases. With this information and information on the required investments the pay-back periods and the ergonomic implications of the various investments were calculated. These numbers are summarized in Table 5-19.

Optimization problem Pay-back period (time- value of money incl.)

Ergonomics (--/-/0/+/++) Use of line balancing application current situation (CS) 129 days 0

Line balance CS + partial removal kitting area 1 year and 341 days -/0

Line balance FS + partial removal kitting area 1 year and 226 days -/0

Line balance CS + Palletizing robot 3 years and 121 days +

Automated Kanban system 3 years and 316 days 0

Table 5-19 Summary of Pay-back period results

Given this overview it is most interesting to partially remove the kitting area and use the line balancing program to rebalance the production line. However, this chapter also discussed the soft wins that go hand in hand with implementation of for example the automated Kanban system. It is important to take into account these soft wins as well when making a final decision. We conclude that the soft wins will benefit the operations extremely and are well worth the 316 days of extra pay-back time. From an ergonomics perspective it would be best to implement the palletizing robot from the available options, but the ergonomic implications of the other options are not bad either. The economic evaluation of the palletizing robot has to be evaluated with caution. The evaluation does not take into account the structured supply of the boilers to the robot. It is assumed, that including these costs will have a significant negative influence on the costs as the complete production line has to be rebuild. The combined implementation of the palletizing robot and the removal of the kitting area is found to have a worse pay-back period than implementation of either one of the systems. Simultaneous implementation of an automated Kanban system and another change is possible. These changes do not affect each other in terms of cycle time and pay-back period.

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