| 1. |
- Hermansson, Tomas, 1979, et al.
(författare)
-
Quasi-static path optimization for industrial robots with dress packs
- 2021
-
Ingår i: Robotics and Computer-Integrated Manufacturing. - : Elsevier BV. - 0736-5845. ; 68
-
Tidskriftsartikel (refereegranskat)abstract
- Problems with robot dress packs are a major reason for on-line adjustments of robot programs and down-time in robot stations. It is therefore of high value if the physical behaviour of the dress packs can be considered with simulation methods already during the off-line programming process for a robot station. This paper presents a method for quasi-static path optimization for an industrial robot with respect to its deformable dress pack. Given an initial collision-free path generated by an automatic path planner, the via point configurations of the path are optimized with respect to the performance aspects of the dress pack. The method is derived from a general framework for parameter optimization of a mechanical system subject to quasi-static motions and deformations. The optimal parameter values are obtained from numerical solutions to a non-linear programming problem in which the static equilibrium equations of the system hold at discrete times. Due to the large-scale nature of this problem, a dress pack is modelled as a discrete Cosserat rod, which is the preferred choice for modeling large spatial deformations of a slender flexible structure with coarse discretization. The method is applied to an industrial robot moving in-between stud welding operations in a stud welding station. The optimized path reduces the stress in the dress pack and keeps the dressed robot from the surrounding geometry with a prescribed safety clearance during the entire robot motion.
|
|
| 2. |
- Isaksson, Ola, 1969, et al.
(författare)
-
Multi-domain design assessment for aerospace components including weld accessibility
- 2021
-
Ingår i: Proceedings of the Design Society. - : Cambridge University Press (CUP). - 2732-527X. ; Volume 1 - August 2021, s. 2217-2225
-
Konferensbidrag (refereegranskat)abstract
- Aeroengine manufacturers need to better include assessment of risk and cost for realising the novel products needed to meet the ambitions sustainability driven targets for air transport. Radical technologies are needed that simultaneously require critical manufacturing processes to be assessed already in conceptual design. In this paper, a multi-domain framework for conceptual design and evaluation is proposed that provide the ability to interactively explore the concepts that simultaneously allow a wider range of architectures can be assessed and still include weldability of the concepts. It has been demonstrated how high level, and function driven conceptual design alternatives can be modelled and evaluated to analyse risk and resilience of architectures. Geometrical concepts generated for the most interesting regimes using design of experiments covering a desired design space. For each CAD-model the welding process can be simulated to assess feasibility and lead time for welding, and return quantified results to be included in an integrated results data set for interactive decision making. The paper is the first report from a research project that improve concurrent design of product and production concepts.
|
|
| 3. |
- Landahl, Jonas, 1986, et al.
(författare)
-
Using product and manufacturing system platforms to generate producible product variants
- 2016
-
Ingår i: Procedia CIRP. - : Elsevier BV. - 2212-8271. ; 44, s. 61-66
-
Konferensbidrag (refereegranskat)abstract
- Product platforms have proven efficient as a means to reduce lead-time and increase product quality simultaneously. When using platforms to generate a family of products, the number of variants that need to be managed in manufacturing increases. To succeed with this, the manufacturing system needs to be maintained in a similar level of flexibility as the product platform. However, there is seldom a joint decision behind each and every conceptual product variant during development, regarding capability in manufacturing. For example, when considering producibility, some product variants require better tolerances than what the manufacturing processes can deliver. This uncertainty can be reduced, by making producibility analyses of a set of conceptual product variants. By performing several different analyses, knowledge can be gained, and joint decisions can be made about cross product-manufacturing aspects. The activities can be systematically arranged to gradually eliminate unfeasible conceptual product variants. In this paper we show how an integrated PLM architecture can be used to create sufficient knowledge as a basis for joint product and manufacturing decisions. The utmost company benefit of this is to reduce lead-time by taking manufacturing capability into account when developing product families.
|
|
| 4. |
- Li, Yi, et al.
(författare)
-
Visualization of part surfaces for identifying feasible assembly grasp locations
- 2017
-
Ingår i: The 5th International Digital Human Modeling Symposium (DHM 2017).
-
Konferensbidrag (refereegranskat)abstract
- As the first step toward automatic grasp planning in the IPS (Industrial Path Solutions) platform with aDHM (Digital Human Modeling) tool called IMMA (Intelligently Moving Man-ikins), two methods namedPointwise Shortest Distance and Environment Clearance are presented in this paper to color part surfaces by taking environmental constraints into ac-count so that aDHM tooluser can easily identify feasiblegrasp locations for a manikin. Theimplementation of these two methods are robust enoughto handle triangle meshes with commongeometric flaws such as cracks andgaps. In fact, with the help of Visual Shellalgorithmimplemented on Graphics Processing Unit (GPU),even meshes within-consistently oriented normal vectorscan be handled. Currently, we are planning to conduct anindustrial user study, where assembly simulation expertswill be asked to specify man-ikin’s hand grips using IMMA with and without the help of the proposed methods, toprove that the proposed methodsindeedenhance the flexibility and hence the usability for the assembly simulation experts. Visualization of part surfaces for identifying feasible assembly grasp locations. Available from: https://www.researchgate.net/publication/322581783_Visualization_of_part_surfaces_for_identifying_feasible_assembly_grasp_locations [accessed Jan 19 2018].
|
|
| 5. |
|
|
| 6. |
- Spensieri, Domenico, 1978, et al.
(författare)
-
Collision-free robot coordination and visualization tools for robust cycle time optimization
- 2021
-
Ingår i: Journal of Computing and Information Science in Engineering. - : ASME International. - 1530-9827 .- 1944-7078. ; 21:4
-
Tidskriftsartikel (refereegranskat)abstract
- This paper presents novel algorithms and visualization tools for avoiding collisions and minimizing cycle time in multi-robot stations by velocity tuning of robot motions. These tools have the potential to support product/manufacturing engineers in the practical task of adding synchronization instructions to robot programs to overcome the challenges in terms of product design, cycle time, quality control, and maintenance including re-usability of coordination schemes. We propose a range of techniques to achieve that, when additional requirements make the best coordination strategy hard to be chosen. Indeed, our main contributions are (i) considering and minimizing delays introduced by limitation in hardware synchronization mechanisms, (ii) highlighting insights on the relationship between a 3D working space and a path coordination space, and (iii) a computational tool for visualization of shared areas in both work space and path coordination space. Different strategies based on the developed algorithms are evaluated by successfully automatically solving industrial test cases from inspection measurement applications in the automotive industry. A study about how cycle time robustness is significantly influenced by variation in the robot motion execution times is also given.
|
|
