Pierre LarochelleAndrew P. MurrayCarl NelsonNina Robson...
2页
查看更多>>摘要：This special issue constitutes selected papers from the refereed conference proceedings of the 1st Mechanical Systems and Robotics Symposium, MSR 2020, scheduled to be held in Rapid City South Dakota, USA, in May 2020. MSR is a series of international conferences hosted in North America that focuses on specialised robotic systems, soft, wearable and origami robotic systems, applications to walking, flying, climbing, ground, underground, swimming, and space systems, human rehabilitation and performance augmentation, design and analysis of mechanisms and machines, human-robot collaborative systems, service robotics, mechanical systems and robotics education, commercialisation of mechanical systems and robotics, and related topics.
查看更多>>摘要：This paper presents an approach to rigid flat origami design, with applications including a portable boat and travel-size musical instrument. The conditions for rigid flat folding are summarised, and a set of procedural design guidelines are presented systematically to apply these principles, including a symmetry-based strategy for achieving additional compactness, a corner-fold insertion technique to achieve constraint in the desired shape while preserving mobility for transition to the flat configuration, and a plane-assignment algorithm for the flat configuration. The portable boat is developed from a symmetric, four-vertex origami pattern, and a simplified construction is identified through eliminating the panels which remain adjacent in the open and flat-folded configurations. The musical instrument is a modified box in the shape of an octagonal right prism, and is designed using methods similar to those used in the boat construction. Prototyping methods for both objects, and light testing, are presented.
查看更多>>摘要：A developable mechanism is a linkage that has its axes located on a developable ruled surface and its links shaped to fit this surface in a stowed configuration. Our goal is to find configurations for both planar and spherical four-bar linkages in which points on the four joint axes lie on a circle. This configuration can form the stowed position of the linkage with its links shaped to form a cylinder in the planar case and a cone for the spherical case called the conformed position. The result is a cylindrical or conical developable mechanism respectively. We provide two derivations for both the planar and spherical cases. One uses the formulas for the radii of the open and crossed form of these mechanisms and the other computes the configuration directly. We demonstrate these results with examples.
Lance P. HyattJacob R. GreenwoodJared J. ButlerSpencer P. Magleby...
22页
查看更多>>摘要：Planar and spherical mechanisms can be mapped to regular cylindrical and circular conical developable surfaces using cyclic quadrilaterals. The link lengths and link angles can be used in equations to calculate the circumcircle of a cyclic quadrilateral to find the radius or cone angle of a developable surface. Two other numerical and graphical methods to map mechanisms to these surfaces are discussed and expanded. Useful properties of developable mechanisms are also identified using cyclic quadrilaterals. While Grashof mechanisms can be mapped to developable surfaces in either their open or crossed configurations, the only way to map a non-Grashof mechanism to a cylindrical or conical surface is in its open configuration. Extramobile and intramobile behaviour can be predicted based the cyclic quadrilateral's position within the circumcircle and the mechanism's grounded link. The possible configurations are tabulated and analysed.
查看更多>>摘要：This paper presents an implementation of a path tracking algorithm and end game for the homotopy solution of mechanism synthesis equations using a graphical processing unit, or GPU. The goal is to have the GPU execute a large number of path tracking solutions in parallel in order to identify design candidates that satisfy a set of kinematic synthesis polynomial equations. Effective use of the GPU requires that the processors execute the same instruction set. This imposes constraints on the structure of the path tracker and the end game. In this paper, we present that our implementation of GPU-based polynomial homotopy solver and end game. We demonstrate the implementation by solving the five position planar four bar synthesis problem for a given set of task positions.
查看更多>>摘要：Active fuel management is a technology that allows a multi-cylinder internal combustion engine to shut off a bank of cylinders to reduce engine power output as needed to match driving conditions and driver power demand. This variation in engine power is taken a step further with a technology known as dynamic fuel management, wherein individual cylinders of a multi-cylinder engine may be turned off as needed. This approach allows a finer resolution in engine power variation. Dynamic fuel management allows an engine to operate with lower pumping losses, thereby maximising the potential for capturing regenerative braking energy. In this paper, the synergies of such an engine equipped with dynamic fuel management, coupled to an electrified driveline incorporating a 48V P1 architecture, are investigated. Detailed MATLAB models are developed to understand the influence of system parameters as well as to identify the optimal engine/motor torque arbitration required for maximum fuel economy. It is shown that the combination of dynamic fuel management and P1 hybridisation can provide a substantial fuel economy improvement.
查看更多>>摘要：In this paper, improvements of the basic twisting string actuation commonly found in the literature are demonstrated based on the addition of two types of passive elements in order to optimise mechanical efficiency. First, the motion speed is increased with non-cylindrical rigid wrapping. Secondly, passive compliant load adjusters are added to improve the overall mechanical advantage of the transmission in reaction to varying loads. A mathematical model of the new system is first detailed in the paper and provides numerical simulations subsequently validated with experimental results. The impact on the important characteristics of the transmission of the design parameters are shown in details and the simulations highlight several improvements of our proposed design compared to existing twisting wire systems. Finally, this novel transmission with a compliant adjuster is used to drive an underactuated robotic finger to demonstrate its effectiveness.
查看更多>>摘要：Larger workspace volume is one of the most important objectives in the optimum design of robot manipulator. In the present study, the workspace volume of a 3R manipulator has been maximised. The nonlinear constrained optimisation problem has been solved using the particle swarm optimisation (PSO) and a hybrid PSO and gravitational search algorithm (GSA). The proposed algorithm combines the search method of PSO and GSA with enhanced exploration ability to achieve higher workspace volume as compared to the established available results. Further, the total void cross section area has been estimated and a quantitative analysis of the results has been made to identify the key influencing kinematic parameters and prioritise the constraints. Applications of the hybrid algorithm on two industrial manipulators are presented as case studies. An important implication of this article is that the proposed hybrid algorithm provides encouraging result in terms of objective function values and CPU time.
查看更多>>摘要：Simulations of several repetitive mechanisms, some of them considered difficult to perform, have been done relatively easily using for loops and the MeKin2D modular-kinematics subroutines. These simulations include generation of multiple couple-curves, wicked-vane and aperture mechanisms, feathering paddlewheels, radial engines and a folding pop riveter. For the former two mechanisms, in addition to motion simulation, shaking-force and mechanical-advantage analyses have also been performed, respectively. For a better understanding of the computer implementations of these simulations, their source code is also provided as an Appendix to the paper.
A. Padmanabha ReddyC. SateeshaAther Aziz RainaS. H. Manjula...
17页
查看更多>>摘要：In this paper, we propose different procedure to solve the problem of linear system of Fredholm integral equations with constant coefficients. The proposed method gives the rapidly convergent successive approximation to the analytic solution. The reliability and efficiency of the method are illustrated by investigating the convergence results for some problems. In fact, comparisons are made between the contributed scheme and the generated results.
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