Compensating Pose Uncertainties through Appropriate Gripper Finger Cutouts

Abstract The gripper finger design is a recurring problem in many robotic grasping platforms used in industry. The task of switching the gripper configuration to accommodate for a new batch of objects typically requires engineering expertise, and is a lengthy and costly iterative trial-and-error process. One of the open challenges is the need for the gripper to compensate for uncertainties inherent to the workcell, e.g. due to errors in calibration, inaccurate pose estimation from the vision system, or object deformation. In this paper, we present an analysis of gripper uncertainty compensating capabilities in a sample industrial object grasping scenario for a finger that was designed using an automated simulation-based geometry optimization method (Wolniakowski et al., 2013, 2015). We test the developed gripper with a set of grasps subjected to structured perturbation in a simulation environment and in the real-world setting. We provide a comparison of the data obtained by using both of these approaches. We argue that the strong correspondence observed in results validates the use of dynamic simulation for the gripper finger design and optimization.

Download Full-text

Automated Shape Optimization of Orienting Devices for Vibratory Bowl Feeders

Journal of Manufacturing Science and Engineering ◽

10.1115/1.4025089 ◽

2013 ◽

Vol 135 (5) ◽

Cited By ~ 7

Author(s):

Daniel Hofmann ◽

Hongrong Huang ◽

Gunther Reinhart

Keyword(s):

Shape Optimization ◽

Good Accuracy ◽

Random Search ◽

Optimization Technique ◽

Trial And Error ◽

Shape Variation ◽

Search Optimization ◽

Simulation Based ◽

Automated Simulation ◽

Small Parts

Orienting devices for vibratory bowl feeders are still the most widely used system for the automated sorting and feeding of small parts. The design process of these orienting devices has recently been supported by simulation methods. However, this merely shifts the well-known trial-and-error-based adaption of the orienting device's geometry into virtual world. Yet, this does not provide optimal design and, furthermore, requires strong involvement of the developer due to manual shape variation. This paper proposes an optimization algorithm for the automated simulation-based shape optimization of orienting devices for vibratory bowl feeders. First, general formalisms to state the multiobjective optimization problem for arbitrary types of orienting devices and feeding parts are provided. Then, the implementation of the algorithm is described based on Bullet Physics Engine and random search optimization technique. Finally, comparison of simulation results with experimental data point out good accuracy and, thus, great potential of the developed shape optimization software.

Download Full-text

An enhanced Monte Carlo simulation–based design and optimization method and its application in the speed reducer design

Advances in Mechanical Engineering ◽

10.1177/1687814017728648 ◽

2017 ◽

Vol 9 (9) ◽

pp. 168781401772864 ◽

Cited By ~ 7

Author(s):

Rong Yuan ◽

Haiqing Li ◽

Zicheng Gong ◽

Mingzhe Tang ◽

Wei Li

Keyword(s):

Monte Carlo Simulation ◽

Monte Carlo ◽

Optimization Method ◽

Design And Optimization ◽

Simulation Based Design ◽

Simulation Based ◽

Speed Reducer

Download Full-text

Design and Optimization of Hybrid Compliant Narrow-Gauge Surgical Forceps

ASME 2010 Conference on Smart Materials, Adaptive Structures and Intelligent Systems, Volume 1 ◽

10.1115/smasis2010-3732 ◽

2010 ◽

Cited By ~ 1

Author(s):

Milton E. Aguirre ◽

Mary Frecker

Keyword(s):

Compliant Mechanism ◽

Geometry Optimization ◽

Optimization Method ◽

Design Methods ◽

Geometric Constraints ◽

Infiltration Process ◽

Design And Optimization ◽

Grasping Forces ◽

Tool Performance ◽

Yttria Partially Stabilized Zirconia

This work describes a design and optimization method for developing hybrid, multi-material, compliant instruments which are expected to be useful in mini-laparoscopy and natural orifice translumenal endoscopic surgery. These two-material devices are designed specifically for Penn State’s lost mold rapid infiltration process, which is capable of fabricating hundreds of freestanding meso-scale parts in parallel. New narrow-gauge surgical procedures impose severe geometric constraints that challenge traditional compliant mechanism design methods. Since narrow-gauge constraints leave geometry optimization ineffective, new design methods are explored to improve the performance of a 1 mm diameter contact-aided compliant forceps. By considering hybrid designs, new design possibilities are enabled through material variation. The hybrid forceps has desired regions of flexibility and stiffness that can be isolated to improve tool performance. For instance, a hybrid forceps can be designed with greater flexibility in some regions to provide larger jaw openings while maintaining high stiffness in other regions to obtain large grasping forces, both vital features in a surgical forceps. Using ANSYS to model large deformation and contact, an optimization problem is formulated to maximize tool performance and to determine optimal segregation of hybrid materials considering a range of modulus ratios. Materials under consideration include nanoparticulate 3 mol% yttria partially stabilized zirconia (3YSZ) and austenitic (300 series) stainless steel. All results are compared to previously optimized homogeneous designs.

Download Full-text

Efficient Multi-Objective CFD-Based Optimization Method for a Scroll Distributor

Energies ◽

10.3390/en14020377 ◽

2021 ◽

Vol 14 (2) ◽

pp. 377

Author(s):

Damian Obidowski ◽

Mateusz Stajuda ◽

Krzysztof Sobczak

Keyword(s):

Energy Savings ◽

Axisymmetric Flow ◽

Geometry Optimization ◽

Optimization Method ◽

Problem Size ◽

Computational Point ◽

Multi Objective ◽

Flow Problems ◽

Multi Objective Genetic Algorithm ◽

Separation Zones

An efficient approach to the geometry optimization problem of a non-axisymmetric flow channel is discussed. The method combines geometrical transformation with a computational fluid dynamics solver, a multi-objective genetic algorithm, and a response surface. This approach, through geometrical modifications and simplifications allows transforming a non-axisymmetric problem into the axisymmetric one in some specific devices i.e., a scroll distributor or a volute. It results in a significant decrease in the problem size, as only the flow in a quasi-2D section of the channel is solved. A significantly broader design space is covered in a much shorter time than in the standard method, and the optimization of large flow problems is feasible with desktop-class computers. One computational point is obtained approximately eight times faster than in full geometry computations. The method was applied to a scroll distributor. For the case under analysis, it was possible to increase flow uniformity, eradicate separation zones, and increase the overall efficiency, which was followed by energy savings of 16% for the scroll. The results indicate that this method can be successfully applied for the optimization of similar problems.

Download Full-text

Distributed, multiplatform high ﬁdelity human-patient simulation environment: a global-range simulation-based medical learning and training network

International Journal of Healthcare Technology and Management ◽

10.1504/ijhtm.2005.006993 ◽

2005 ◽

Vol 6 (4/5/6) ◽

pp. 500 ◽

Cited By ~ 1

Author(s):

Dag K.J.E. Von Lubitz ◽

Howard Levine

Keyword(s):

Patient Simulation ◽

High Fidelity ◽

Human Patient Simulation ◽

Simulation Environment ◽

Human Patient ◽

Simulation Based ◽

Medical Learning ◽

And Training

Download Full-text

Simulation-Based Hybrid Optimization Method for the Digital Twin of Garment Production Lines

Journal of Computing and Information Science in Engineering ◽

10.1115/1.4050245 ◽

2021 ◽

Vol 21 (3) ◽

Author(s):

Woo-Kyun Jung ◽

Young-Chul Park ◽

Jae-Won Lee ◽

Eun Suk Suh

Keyword(s):

Expert Knowledge ◽

Structural Characteristics ◽

Optimization Method ◽

Hybrid Optimization ◽

Optimization Process ◽

Production Lines ◽

Distribution Method ◽

Workload Analysis ◽

Hybrid Optimization Method ◽

Simulation Based

AbstractImplementing digital transformation in the garment industry is very difficult, owing to its labor-intensive structural characteristics. Further, the productivity of a garment production system is considerably influenced by a combination of processes and operators. This study proposes a simulation-based hybrid optimization method to maximize the productivity of a garment production line. The simulation reflects the actual site characteristics, i.e., process and operator level indices, and the optimization process reflects constraints based on expert knowledge. The optimization process derives an optimal operator sequence through a genetic algorithm (GA) and sequentially removes bottlenecks through workload analysis based on the results. The proposed simulation optimization (SO) method improved productivity by ∼67.4%, which is 52.3% higher than that obtained by the existing meta-heuristic algorithm. The correlation between workload and production was verified by analyzing the workload change trends. This study holds significance because it presents a new simulation-based optimization model that further applies the workload distribution method by eliminating bottlenecks and digitizing garment production lines.

Download Full-text

A general design and optimization method of tightly-coupled cross-dipoles for base station

12th European Conference on Antennas and Propagation (EuCAP 2018) ◽

10.1049/cp.2018.0367 ◽

2018 ◽

Author(s):

Can Ding ◽

Haihan Sun ◽

Y.J. Guo ◽

R.W. Ziolkowski

Keyword(s):

Optimization Method ◽

Base Station ◽

General Design ◽

Design And Optimization ◽

Tightly Coupled

Download Full-text

Transportation-oriented spatial allocation of land use development: a simulation-based optimization method

SIMULATION ◽

10.1177/0037549720920374 ◽

2020 ◽

Vol 96 (7) ◽

pp. 583-591

Author(s):

Hongzhi Lin ◽

Yongping Zhang

Keyword(s):

Land Use ◽

Urban Development ◽

Simulation Experiment ◽

Optimization Method ◽

Transportation System ◽

Sustainable Urban Development ◽

Total System ◽

Simulation Based ◽

Level Model ◽

Land Use Development

Urban development usually deteriorates the transportation system. For sustainable urban development, policymakers often face the challenging problem of how to optimally allocate overall land use quotas across a number of residential locations according to the performance of the transportation system. This is a kind of Stackelberg competition, where policymakers make land use decisions and travelers make behavioral responses. A novel bi-level model is formulated to solve this problem. The upper-level model minimizes the total system travel time by land use allocation, while at the lower level are sequential models with feedback for transportation system equilibrium. The Dirichlet allocation algorithm, a simulation-based heuristic algorithm, is designed to solve this bi-level model. A simulation experiment using the Nguyen–Dupuis network is then used to verify the proposed model and algorithm. The results from the simulation experiment demonstrate that not only are the model and algorithm operational but that they also provide an effective tool for policymakers to plan for land use development.

Download Full-text