A framework for integrated design of human–robot collaborative assembly workstations

This study presents a methodology used in the design certification of a battery module for electric vehicle applications. The methodology combines virtual and physical techniques to assess the structure under mechanical shock testing, according to the standards’ requirements. Virtual prototyping is used to quantify parameters as stresses and deformations. Performed simulations using the virtual prototype are validated by testing the physical prototype, which allows for assessing various design parameters with a high level of confidence. The testing of a physical prototype is performed using specialized equipment—a mechanical shock test bench—which is developed and manufactured especially for this task. The presented methodology is demonstrated in an industrial use case, and the main contribution of this study is related to the way the combination of virtual and physical prototyping and testing is used.

A layer-based virtual prototyping system for product development

This paper proposes a dexel‐based virtual prototyping system, which builds a virtual prototype with dexels or rectangular strips of solid. The approach resembles the physical fabrication process of most powder‐based rapid prototyping (RP) systems. It simulates an RP process to create a virtual prototype. Colour virtual prototypes may also be fabricated relatively easily. Thus, the designer can perform design validation and accuracy analysis easily in a virtual environment as if using a physical prototype. In addition to numeric quantification of the RP process, the system provides vivid visualisations of the prototype for studying its characteristics. Furthermore, the prototype may be superimposed on the product model, and the areas with dimensional errors beyond design limits may be clearly highlighted for subsequent improvement. The designer may thus analyse and compare the surface texture point‐by‐point of the prototype with the product design.

<div class="section abstract"><div class="htmlview paragraph">The microcellular foam injection molding process for thermoplastic materials provides design flexibility and cost savings opportunities not found in conventional injection molding. This process allows for plastic part design with material wall thickness optimized for functionality.</div><div class="htmlview paragraph">The combination of density reduction and design for functionality can result in material and weight savings of up to 20%. With the correct equipment configuration, mold design, and processing conditions, these microcellular voids are uniform in size and distribution. The use of microcellular foam molding provides significant reductions in cycle time, material consumption, injection pressure, and clamp tonnage.</div><div class="htmlview paragraph">In this work, a physical foam molding process, MuCell, is applied to a polypropylene (PP) composite. The MuCell injection molding process involves the highly controlled use of gas in supercritical state, as the physical blowing agent, to create millions of micron-sized voids in thin wall molded parts (less than 3mm).</div><div class="htmlview paragraph">The results show that a weight reduction can be achieved without significant degradation in mechanical properties, such as stiffness and impact resistance. MuCell also contributes to faster cooling from the melt as well as the elimination of pack and hold phase, which both result in shorter injection molding cycle times and reduced warpage.</div><div class="htmlview paragraph">Once material tests have been completed, final part tests will also be performed, to validate established design specifications. These results presented here indicate that microcellular foam molding technology has good potential to be applied to interior parts of vehicles, contributing to weight reduction and productivity increase.</div></div>

This study explores the development of a novel side core design with an integrated cooling system for the low-pressure die casting (LPDC) of A356 aluminum alloy wheel rims in Indonesia. The objective is to reduce cycle time and minimize casting defects. The methodology involves 3D modeling using SolidWorks and simulations performed with MAGMAsoft to evaluate filling and solidification behavior, air pressure, and air entrapment. Notably, this is the first application of a cooling system in Side cores within the Indonesian automotive industry, motivated by the need to improve production efficiency and product quality, as current manufacturing processes suffer from long cycle times and high defect rates. Simulation results show a significant reduction in cycle time by 72 seconds, improving both efficiency and product quality. This study demonstrates the effectiveness of integrating cooling systems into side cores to enhance the LPDC process.

Dramatically reducing cycle times through flash development

Virtual prototyping of embedded control software in mechatronic systems: A case study

The increasing pressure in the work environment, combined with the intensive use of technology and long working hours, has contributed to the increase in musculoskeletal disorders related to inadequate ergonomic conditions, such as Repetitive Strain Injuries (RSI) and Work-Related Musculoskeletal Disorders (WMSDs). This observational cross-sectional study evaluated the ergonomic conditions and the prevalence of musculoskeletal complaints in 21 technical-administrative employees of a federal university who use computers as their main work tool. For this purpose, the Nordic Musculoskeletal Questionnaire (NMQ) and the Rapid Office Strain Assessment (ROSA) method were applied. The results indicated that the most affected body regions were the shoulders (11), lower back (11) and neck (10), evidencing a high level of discomfort. The ergonomic assessment by the ROSA method showed that many workstations presented high ergonomic risks, indicating the need for immediate corrective interventions. The findings reinforce the importance of ergonomics in preventing musculoskeletal disorders and promoting healthier and more efficient work environments.

This paper presents a formal approach that addresses the reciprocal robots collision avoidance, where two robots need to avoid collisions with each other, while moving in a common workspace. Based on our formulation, each physical robot acts fully independently, communicating with the corresponding virtual prototype and imitating its behavior. Each physical robot reproduces the pathway of its virtual prototype. With a view to collision avoidance, it is necessary to detect a possible collision. This action includes the potentially intersecting regions test of the corresponding virtual prototypes. The estimation of the collision-free actions on the virtual robots and the collaborative work of the physical robots which imitate their virtual prototypes are the original ideas. Based on potentially intersecting regions of the virtual robots, we identified a collision-free motion corridor for two cooperative robots. Using the definition of velocity obstacles, we derived sufficient conditions for the collision-free motion of the two virtual robots. We tested the present approach on several complex simulation scenarios involving two virtual robots and estimating collision-free actions for each of them during the cooperative tasks. The focus of this paper is the identification of the collision-free actions for two virtual robots and their behavioral imitation by the physical robots.

The proficiency of Computer Aided Design (CAD) to save, communicate and render realistic virtual prototypes allows for easier communication and review of proposed design decisions via design reviews. However, the use of virtual prototypes is limited by the realism of the human computer interface. This paper builds on previous research investigating if increasing the realism of input and output interactions between subjects and virtual prototypes will affect user’s ability to analyze an assembly for errors. For this end, two experiments were conducted which asked participants to perform design reviews on assembly models and identify errors in the assembly. The first experiment tested virtual prototype output display factors through subject point of view movement and virtual prototype rotation. The second experiment tested human input factors using different controller setups. It is expected the more realistic virtual prototype rendering and controller input experience will result in more accurate design reviews.

Virtual prototypes are increasingly used in device/driver co-development and co-validation to enable early driver development and reduce product time-to-market. However, drivers developed over virtual prototypes often do not work readily on silicon devices, since silicon devices often do not conform to virtual prototypes. Therefore, it is important to detect the inconsistences between silicon devices and virtual prototypes.

Dynamic Simulation analysis of mechanical system based on the virtual prototyping technology can be used to simulate the actual working condition of machines to be designed. It can shorten the product development cycle by providing convenient amendments to the virtual prototype in accordance with the results of simulation. In this paper, the virtual prototype of the crank-connecting rod mechanism of mud pump was built by using the software Pro/Engineer, then the model was imported into the virtual prototyping software —ADAMS. At the same time, the restrictions and the driving mode were applied to simulate the kinematic process according to the multi-body system dynamics theory. Thus the whole dynamic analysis process of the virtual prototype was completed. Though the process, the movement process graphs such as displacement, velocity and acceleration of the piston were obtained, which validated the availability of the movement model. The design process and methodology adopted in this paper can be a valuable reference for the design and development of similar products.

The use of prototypes in the product development process (PDP) brings maturity to the project, reduces uncertainties, and helps in the conservation of information flow during the whole PDP. Usually, virtual prototypes (VP) are created in CAD/CAE systems, while physical prototypes (PP) are usually manufactured from techniques of material addition. In this reality, the creation/manufacturing of a prototype capable to meet its purpose will depend on the alternative available for its creation/manufacturing, and on the experience of the professional involved (designer). This work proposes a procedure to help in the selection of the best creation/manufacture technique for VP and PP, initially focusing on the automotive sector. The procedure was developed from theoretical backgrounds, discussion and consideration among professionals and scholars. The procedure was evaluated in a field research, where 34 professionals from 23 different companies of the automotive sector had been consulted. The theoretical frameworks, the proposed procedure, and the results of the field research are presented. Finally, the work is finished showing the conclusions and final considerations. The use of this procedure is expected to help experienced professionals and beginners, as well as scholars, in their research, education, and extension activities.

In the design process of complex systems, the use of physical prototypes presents many drawbacks in terms of both costs and time. Virtual prototyping tools allow instead the designer to extensively study the system behavior in a variety of configurations, providing the possibility of performing focussed tests and comparing the effectiveness of different solutions before the physical realization of the prototype. When building the virtual prototype, the choice of a suitable model for each of the interacting components is crucial for achieving reliable results. In the simulation of racing vehicles, such as cars or motorcycles, it is common practice to represent the engine torque by means of stationary maps depending on a finite number of constant values of the throttle fraction and the rotational speed of the crankshaft. Although simple to implement and characterize, such model cannot reproduce dynamic transients, and therefore may not be adequate when a detailed analysis of the vehicle behavior is required. In this paper we present the characterization and identification of a nonlinear dynamic model for a two-stroke internal combustion high-performance engine, to be used in the ADAMS multibody virtual prototyping environment. The model is obtained by using neural networks and validated on experimental data

Young, active disabled people with impairment of lower extremities tend to be as active, as possible considering their disabilities. For purposes of leisure and sport many wheelchair solutions have been already proposed, yet the struggle to provide efficient and economically rational means of transport that increase their mobility is still ongoing. According to various authors lever wheelchairs have certain advantages in the given field: ergonomic work conditions and high human work efficiency resulting from the lever drive concept. In our works we created a pre-prototype of such wheelchair. Our projects goal was to try to implement many different solutions which were to provide rich functionality: adjustment of levers’ length, adjustment of levers’ axis of rotation position, changeable gears including reverse gear, innovative brake mechanism. As a result we could assess which of the functional assumptions were reasonable and easy to implement and which could be useful however make the design very complicated, heavy and thus irrational. Our main conclusion was that if the lever driven wheelchair concept is to become popular, one of the key-issues in their design must be: simplicity. Additional functionality seems attractive during theoretical studies, but it’s implementation very often causes too much complication and weight gain.