Top PDF Analysis of Packaging and Deployment of Ultralight Space Structures

Analysis of Packaging and Deployment of Ultralight Space Structures

Analysis of Packaging and Deployment of Ultralight Space Structures

The momentless-crease force folded (MCFF) technique was developed. It utilizes pressure, line and vertex loads to fold a creased sheet into a tightly packaged configuration. Pressure loads apply follower forces, they are a replacement for rotational boundary conditions. Line and vertex loads keep creases straight, to avoid crumpling. Rotational boundary conditions were tested for the ef- fectiveness on the benchmark problem; however the facets were over-constrained during folding, leading to significant twisting of the facets. At vertices which are over-constrained, removal of the surrounding elements reduces stress concentrations and the force required for folding. Deployment simulations in LS-Dyna starting from packaged configurations found using the MCFF approach qualitatively matched the simulations starting from an initial approximation of the folded state. In particular, the deployment force was zero at two of the three intermediate equilibrium configura- tions. The force peaks were also within 27% of the initially folded simulations. This validates the MCFF approach, compared to starting in an approximation of the folded configuration.
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The Importance of Take-Out Food Packaging Attributes: Conjoint Analysis and Quality Function Deployment Approach

The Importance of Take-Out Food Packaging Attributes: Conjoint Analysis and Quality Function Deployment Approach

Silayoi and Speece (2005) demonstrate that the conjoint study seems to have been an effective way to examine how consumers view packaging, and Surjandari (2010) describes that Conjoint Analysis – QFD is a useful combination of the two methodologies in product development, market segmentation, and the trade off between customers’ requirements in the early stages of the HOQ process. This research examines consumer response packaging using a Conjoint Analysis and Quality Function Deployment (QFD) among consumers for take-out food products in Jakarta, Indonesia. The relationship between consumer choices in various market segments and design characteristics of packaging is a key
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Packaging and Deployment of Large Planar Spacecraft Structures

Packaging and Deployment of Large Planar Spacecraft Structures

Many aspects of the satellite attitude control system are not yet fully specified, and therefore it is difficult to estimate the amplitude and frequency content of the associated loads. However, it will be assumed that the attitude control system has been designed to decouple structural dynamics from the spacecraft attitude dynamics, and thus the attitude control forces will be small. This is a standard technique in the design of attitude control system for flexible spacecraft [67]. Additionally, the actuators can be isolated from the structure using dampers, and thus the vibrational noise from these sources can be reduced. This class of loads will not be considered for this preliminary analysis. Thermal shocks occur each time the satellite transitions from being in the shadow of a celestial body (e.g., the Earth or the Moon) to being in sunlight, or vice versa. For a satellite in a geo- stationary orbit, there are two eclipse periods, situated around the vernal and autumnal equinox, during which the satellite is in eclipse for periods up to 70 minutes. It is expected that the satellite will not operate during these eclipses; it can also be left inoperational for a period of time following the eclipse to return to a steady thermal state. Thus thermal shocks will not be considered for this preliminary analysis.
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Post-launch analysis of the deployment dynamics of a space web sounding rocket experiment

Post-launch analysis of the deployment dynamics of a space web sounding rocket experiment

Lightweight deployable space webs have been proposed as platforms or frames for a construction of structures in space where centrifugal forces enable de- ployment and stabilization. The Suaineadh project was aimed to deploy a 2 × 2 m 2 space web by centrifugal forces in milli-gravity conditions and act as a test bed for the space web technology. Data from former sounding rocket experiments, ground tests and simulations were used to design the structure, folding pattern and control parameters. A developed control law and a re- action wheel were used to control the deployment. After ejection from the rocket, the web was deployed but entanglements occurred since the web did not start to deploy at the specified angular velocity. The deployment dynam- ics was reconstructed from the information recorded in inertial measurement units and cameras. The nonlinear torque of the motor used to drive the reaction wheel was calculated from the results. Simulations show that if the Suaineadh started to deploy at the specified angular velocity, the web would most likely have been deployed and stabilized in space by the motor, reaction wheel and controller used in the experiment.
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The Suaineadh Project : A stepping stone towards the deployment of large flexible structures in space

The Suaineadh Project : A stepping stone towards the deployment of large flexible structures in space

The data management software onboard the central hub must be able to receive input data from two different sources: digital data from the IMUs, and images from the cameras. The camera will output compressed still frames in JPG format. The data needs to be combined, and re-encoded with a time stamp from the main CPU, plus synchronization bits, message ID and checksums in order to verify the entire data packet was received at the receiver on the REXUS platform. For the communications side, the data also include error correction and detection overhead. Once on-board REXUS, the data is stored on the SD memory cards for retrieval and analysis later. A portion of the data will be transmitted to the REXUS service module, and transmitted via downlink to Esrange (SSC ground station located in Kiruna Sweden). Due to the low data rate, only a small portion of the data will be transmitted (~2.5%). The data will therefore have to be sorted. A sorter will look at the timestamps and device IDs from each package transmitted, and select every n th measurement (approximately every 10 th reading) from each IMU to be transmitted down. Message packets will have to re-divide since the requirement for the REXUS- GS downlink is that each word must be a maximum of 24 bits (15 + 9 bits overhead); with 3 ms interrupt spacers between each word. Synchronization and check- sums will be added to verify the data transmission, as well as EDAC protocols. The data will be collected in real-time by a laptop at the GS.
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Design and Characterization of Dual-Matrix Composite Deployable Space Structures

Design and Characterization of Dual-Matrix Composite Deployable Space Structures

Contact in implicit analysis in LS-Dyna is by default ‘sticky’ i.e., once contact has occurred, a large penalty is applied to keep the parts in contact. This prevents the parts from coming in and out of contact and causing instabilities in the analysis. This behavior is controlled by the IGAP parameter of the contact algorithm and can be turned off by changing the parameter from 1 to 2 to disable the contact penalty. Alternatively, the SFS parameter can be modified to scale the penalty. The contact parameters were tuned to compute an accurate folded shape for the hinge. With the default ‘sticky’ contact, the two tape springs remained in contact and would not deploy, resulting in an inversion in the sign of longitudinal curvature in the outer tape spring (Figure 5.12A). Se- lecting IGAP = 2 to disable the contact penalty resulted in contact constraint violations at the tape spring edges unless the time increment was significantly reduced (Figure 5.12B). To enable larger increments, the SFS parameter was scaled down to SFS = 0.01, reducing the contact penalty to 1% of its original value. This setup prevented contact failure while allowing larger time increments and reducing ‘sticky’ contact enough to allow tape spring deployment (Figure 5.12C).
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Analysis and evaluation of a reusable engine packaging system

Analysis and evaluation of a reusable engine packaging system

Rouillard et al (1996) presented an analysis of spectral and statistical characteristics of actual road surface elevation records. A loaded truck experiences vertical acceleration mainl[r]

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Lagrangian and Hamiltonian structures in an integrable hierarchy and space-time duality

Lagrangian and Hamiltonian structures in an integrable hierarchy and space-time duality

We define and illustrate the novel notion of dual integrable hierarchies, on the example of the nonlinear Schrödinger (NLS) hierarchy. For each integrable nonlinear evolution equation (NLEE) in the hierarchy, dual integrable structures are characterized by the fact that the zero-curvature representation of the NLEE can be realized by two Hamiltonian formulations stemming from two distinct choices of the configura- tion space, yielding two inequivalent Poisson structures on the corresponding phase space and two distinct Hamiltonians. This is fundamentally different from the standard bi-Hamiltonian or generally multitime structure. The first formulation chooses purely space-dependent fields as configuration space; it yields the standard Poisson structure for NLS. The other one is new: it chooses purely time-dependent fields as con- figuration space and yields a different Poisson structure at each level of the hierarchy. The corresponding NLEE becomes a space evolution equation. We emphasize the role of the Lagrangian formulation as a uni- fying framework for deriving both Poisson structures, using ideas from covariant field theory. One of our main results is to show that the two matrices of the Lax pair satisfy the same form of ultralocal Poisson algebra (up to a sign) characterized by an r -matrix structure, whereas traditionally only one of them is in- volved in the classical r -matrix method. We construct explicit dual hierarchies of Hamiltonians, and Lax representations of the triggered dynamics, from the monodromy matrices of either Lax matrix. An appeal-
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Synthesis of Polyhydroxybutyrate Particles with Micro-to-Nanosized Structures and Application as Protective Coating for Packaging Papers

Synthesis of Polyhydroxybutyrate Particles with Micro-to-Nanosized Structures and Application as Protective Coating for Packaging Papers

chemicals like 3-(trimethoxysilyl) propyl methacrylate (MPS) or silanes, acted as highly hydrophobic materials when coated over papers [12, 13]. In addition, a paper coating with organic nanoparticles of styrene maleimide showed high surface hydrophobicity and improved water repellency with self-cleaning ability [14, 15]. However, only few articles described the fabrication of highly hydrophobic papers obtained by purely using biopolymers as a coating. In one study, cellulose has been exploited as a nanoscale coating for the fabrication of superhydrophobic papers using porous structured microparticles of surface modified nanofibrillated cellulose (NFC) [16]. The microparticles were formed by spray drying of solvent-based NFC, followed by quick drying and modification by fluorinated trichlorosilane surfactant. Similarly, cellulose stearoyl ester nanoparticles were made from solution via nanoprecipitation and spray-coated over papers to provide structured superhydrophobic surfaces with a water contact angle larger than 150°, exhibiting self-cleaning properties [17], while the surface hydrophobicity of these papers can be further tuned by thermal annealing. In another example, the bacterial polyhydroxybutyrate (PHB) polymer was applied on paper and transformed into micro- or nanoparticles through a phase-separation technique in direct contact with paper, providing high hydrophobicity [18]: however, the need for the long immersion times (12 hr) of the native PHB-coated paper in an ethanol/water coagulation bath resulted into the swelling of paper fibers and decrease in mechanical properties. Previously, PHB has been applied as a continuous film on paper by casting from a chloroform solution, resulting in lower moisture and water absorption in parallel with high surface hydrophobicity for PHB concentrations above 10 wt% [19]. Advantageously, the integration of NFC may further improve the barrier properties due to the intrinsic oxygen barrier resistance of fibrillated cellulose, as demonstrated before in combinations with PLA [20] and Shellac [21]. The application of PHB as a food packaging material has also been critically described in a review, indicating advantages, drawbacks and several routes for overcoming these drawbacks [22].
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A Packaging/foodservice analysis: a fruit-filling study

A Packaging/foodservice analysis: a fruit-filling study

9 CHAPTER REVIEW OF THE This on the chapter needs were food of packaging to the relates includes a commercial product, service specific frozen, fillings The in this of foodservice of and[r]

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Lagrangian and Hamiltonian structures in an integrable hierarchy and space–time duality

Lagrangian and Hamiltonian structures in an integrable hierarchy and space–time duality

We define and illustrate the novel notion of dual integrable hierarchies, on the example of the nonlinear Schrödinger (NLS) hierarchy. For each integrable nonlinear evolution equation (NLEE) in the hierarchy, dual integrable structures are characterized by the fact that the zero-curvature representation of the NLEE can be realized by two Hamiltonian formulations stemming from two distinct choices of the configura- tion space, yielding two inequivalent Poisson structures on the corresponding phase space and two distinct Hamiltonians. This is fundamentally different from the standard bi-Hamiltonian or generally multitime structure. The first formulation chooses purely space-dependent fields as configuration space; it yields the standard Poisson structure for NLS. The other one is new: it chooses purely time-dependent fields as con- figuration space and yields a different Poisson structure at each level of the hierarchy. The corresponding NLEE becomes a space evolution equation. We emphasize the role of the Lagrangian formulation as a uni- fying framework for deriving both Poisson structures, using ideas from covariant field theory. One of our main results is to show that the two matrices of the Lax pair satisfy the same form of ultralocal Poisson algebra (up to a sign) characterized by an r -matrix structure, whereas traditionally only one of them is in- volved in the classical r -matrix method. We construct explicit dual hierarchies of Hamiltonians, and Lax representations of the triggered dynamics, from the monodromy matrices of either Lax matrix. An appeal-
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EHT Constraint on the Ultralight Scalar Hair of the M87 Supermassive Black Hole

EHT Constraint on the Ultralight Scalar Hair of the M87 Supermassive Black Hole

The scenario in this paper is therefore that the M87 BH is hairy, due to an appropriate ultralight scalar field. Appropriate means its mass is in the right range to make the superradiant instability of the original Kerr BH grow in a sufficiently small fraction of the Hubble time, yielding a hairy BH that is stable in a cosmological time scale. Since the shadows of a Kerr and a hairy BH with the same total mass and angular momentum differ [17], and since the EHT observation is compatible with the M87 BH being of Kerr type, we shall then inquire how much the EHT observations constrain the hair. As we shall see, for the most interesting mass ranges, as to make the hairy BH dynamically viable, the EHT constraint is weak, and it is essentially compatible with a hairy BH that could have dynamically formed from superradiance and it is in a long lived, albeit not absolutely stable, state.
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Reconfiguring smart structures using phase space connections

Reconfiguring smart structures using phase space connections

In general, non-linear dynamical systems typically posses a number of equilibria which may be connected through paths in the phase space of the system. In particular, equilibria with both stable and unstable manifolds may be connected through so-called heteroclinic connections [9]. Here, a manifold is defined as a surface embedded in phase space. The unstable manifold then represents the family of trajectories diverging from an equilibrium point, while the stable manifold represents the family of trajectories asymptotically approaching an equilibrium point. A heteroclinic connection is formed if the unstable manifold of an equilibrium point intersects the stable manifold of another distant equilibrium point in phase space. These phase space structures have important applications in diverse fields such as mechanics [10], astrodynamics [11] and fluids [12]. More complex phase space structures, termed heteroclinic networks, can then be formed from an assembly heteroclinic connections [13].
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DOAS measurements of NO 2from an ultralight aircraft during the Earth Challenge expedition

DOAS measurements of NO 2from an ultralight aircraft during the Earth Challenge expedition

The Earth Challenge expedition (De Maegd, 2010), which took place in 2009, involved four ultralight aircraft flying from Australia to Belgium. It provided an opportunity to de- velop and test a new compact DOAS instrument, namely the Ultralight Motorized-DOAS (ULM-DOAS). In comparison with previous airborne DOAS experiments (e.g. Bruns et al., 2006; Prados-Roman et al., 2011; Merlaud et al., 2011), the optical set-up is very simple. We just record the scattered light intensity at the horizon within a large field of view without any telescope or scanner. However, this measure- ment geometry optimizes the sensitivity to boundary layer NO 2 while it limits the errors due to aircraft attitude (pitch,
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A Study of Unscented Kalman Filter Performance in the Ultralight Coupled Integration System

A Study of Unscented Kalman Filter Performance in the Ultralight Coupled Integration System

In Sect. 2 we have deduced the state-space equation of a kind of typical GNSS/INS integrated navigation filter in UTC system. It seems that a good result will be produced as long as the UKF method is applied. However, there are still some problems to be solved owing to the inherent characteristics of the UKF algorithm. The uncertainty in the model and noise can also leads to the decrease of the estimation accuracy, or even worse, the divergence of the final estimation. In Sect. 3 we suppose the covariance matrix of the noise is known in the system model. However, the covariance matrix data is difficult to obtain in most situations. It can be proved that with the aid of the maximum likelihood estimate and the EM algorithm, the robustness and the accuracy of the UKF are improved without clear information of the noise [9]. Based on the theory above, a kind of advanced UKF is proposed in this paper.
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Model Predictive Control Structures in Non Minimal State Space

Model Predictive Control Structures in Non Minimal State Space

N ext, Sections 8.3 and 8.4 present two approaches th a t directly apply MPC to th e SDP system. As already stated before, there are close parallels of SDP systems w ith TV P systems. However, in TV P systems the system param eters vary slowly (see Guo and Rugh, 1995; Hunt and Johansen, 1997; Shamma and Xiong, 1999; Stilwell and Rugh, 2002, for some examples of dealing w ith stability of T V P systems) while the param eter state dependency in SDP systems can lead to rapid changes in the system dynamics. Since stability results of TV P systems are based on the slow param eter variation, they cannot be used in analysing stability for SDP models. Earlier work of Kouvaritakis et al. (1999) has addressed the issue of stability of M PC controlled non-linear systems by linearising at every sampling instant. Although this approach is eventually based on a piecewise linear model (as in the case of SDP systems), their analysis requires a control trajectory for the initial non-linear system which is not the way the non-linearity is dealt with here.
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ADVANCEMENT IN CONVENTIONAL PACKAGING – EDIBLE PACKAGING

ADVANCEMENT IN CONVENTIONAL PACKAGING – EDIBLE PACKAGING

Edible films have coatings have gained popularity and a lot of research is being carried out in the field. A lot of work has been carried out at pilot level but commercialization is still a far fetched dream. Edible packaging offers a lot of advantages over traditional synthetic polymers. Researches are trying to advance edible packaging for enhancing shelf life, retarding deterioration and keeping safety of food packed. [48] Edible packaging though, cannot be used for long-term storage since they are biodegradable. [49] Thus, to enable edible packaging to work upfront with traditional packaging system, durability for longer periods is the need. Another hurdle in the large-scale usage of edible packaging is cost of manufacturing. In today’s scenario it is quite difficult to deliver edible packaging at the price of traditional packaging. To cease down te cost researchers are targeting waste by products of food industry in the synthesis of edible films and coatings thereby solving the dual problem of cost and global pollution.
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Results of REXUS12's Suaineadh Experiment : Deployment of a spinning space web in micro gravity conditions

Results of REXUS12's Suaineadh Experiment : Deployment of a spinning space web in micro gravity conditions

On the 19th of March 2012, the Suaineadh experiment was launched onboard the sounding rocket REXUS12 (Rocket Experiments for University Students) from the Swedish launch base ESRANGE in Kiruna. The Suaineadh experiment served as a technology demonstrator for a space web deployed by a spinning assembly. The deployment of this web is a stepping stone for the development of ever larger structures in space. Such a structure could serve as a substructure for solar arrays, transmitters and/or antennas. The team was comprised of students from the University of Strathclyde (Glasgow, UK), the University of Glasgow (Glasgow, UK) and the Royal Institute of Technology (Stockholm, Sweden), designing, manufacturing and testing the experiment over the past 24 months. Following launch, the experiment was ejected from the ejection barrel located within the nosecone of the rocket. Centrifugal forces acting upon the space webs spinning assembly were used to stabilise the experiment’s platform. A specifically designed spinning reaction wheel, with an active control method, was used. Once the experiment’s motion was controlled, a 2 m by 2 m space web is released. Four daughter sections situated in the corners of the square web served as masses to stabilise the web due to the centrifugal forces acting on them. The four daughter sections contained inertial measurement units (IMUs). Each IMU provided acceleration and velocity measurements in all three directions. Through this, the positions of the four corners could be found through integration with respect to known time of the accelerations and rotations. Furthermore, four cameras mounted on the central hub section captured high resolution imagery of the deployment process. After the launch of REXUS12, the recovery helicopter was unable to locate the ejected experiment, but 22 pictures were received over the wireless connection between the experiment and the rocket. The last received picture was taken at the commencement of web deployment. Inspection of these pictures allowed the assumption that the experiment was fully functional after ejection, but perhaps through tumbling of either the experiment or the rocket, the wireless connection was interrupted. A recovery mission in the middle of August was only able to find the REXUS12 motor and the payload impact location.
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An evaluation of space-filling information visualizations for depicting hierarchical structures

An evaluation of space-filling information visualizations for depicting hierarchical structures

The two visualization techniques we examine in this study are relatively similar and are examples of space-"lling hierarchical visualizations. Many other types of visualiz- ations for hierarchies do exist such as traditional 2D trees (Wetherell & Shannon, 1979; Kumar, Plaisant & Shneiderman, 1997), 3D cone trees (Robertson, Card & Mackinlay, 1993), hyperbolic trees (Lamping & Rao, 1996), pyramid-style displays (Beaudoin, Parent & Vroomen, 1996), and even outline-oriented views such as the Windows NT Explorer. Each of the di!erent visualization styles better facilitates a di!erent set of information exploration tasks. We focused on the two space-"lling approaches because they seem well-suited to tasks involving "le attributes such as type and size, and because
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packaging innovations THE DETMOLD PACKAGING GROUP

packaging innovations THE DETMOLD PACKAGING GROUP

Industrial’s range of Flat and Satchel Bags offer cost-effective packaging solutions. Applications include Can-End Bags, Satchel Baler Bags and Window Bread Bags. As well as Sterilising Bags produced from medical barrier paper that allows steam and air to pass through under pressure, yet stops bacterial penetration under normal atmospheric conditions. Detmold Industrial Packaging is the major supplier of SOS Bags in Australia and a key supplier in the Asia Pacifi c region, Middle East and South Africa. SOS Bags range from 500g to 20kg in capacity. With six separate printing faces on the bag, SOS Bags provide maximum branding opportunities and retail shelf appeal. Examples of products used for SOS Bags include fl our, sugar, bread mix, pet litter and charcoal products.
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