The contribution of this paper is the expansion of the range of possibilities in the analysis, planning, and control of contact tasks. The successful execution of any contact task fundamentally requires the application of wrenches (forces and moments) consistent with the task. We develop an algorithm for computing the entire set of external wrenches consistent with achieving a given augmented c...

Many types of common objects, such as tools and vehicles, usually move in simple ways when they are wielded or driven: the natural axes of the object tend to remain aligned with the local trihedron defined by the object’s trajectory. Based on this observation we use a model called Frenet-Serret motion which corresponds to the motion of a moving trihedron along a space curve. Knowing how the Fre...

Existing penalty-based haptic rendering approaches are based on the penetration depth estimation in strictly translational sense and cannot properly take object rotation into account. We propose a new six-degree-of-freedom (6-DOF) haptic rendering algorithm which is based on determining the closest-point projection of the inadmissible configuration onto the set of admissible configurations. Ene...

This paper focuses on planar manipulators built upon stacking a series of tensegrity X-joints. The are actuated with four tendons, have different numbers modules, or without offsets. objective this work is to study the influence offsets and number modules size wrench-feasible workspace (WFW). comparison analysis conducted basis equal manipulator height, width mass maximal actuation forces. spri...

To provide a means for comparing impact wrenches and similar tools, the international standard ISO 8662-7 prescribes a method for measuring the vibrations at the handles of tools during their operations against a cotton-phenolic braking device. To improve the standard, alternative loading mechanisms have been proposed; one device comprises aluminum blocks with friction brake linings, while anot...

Grasp planning and optimization have been hot topics in the last decade. Due to the complexity of generating good grasps in analytic form for arbitrary objects, most of the proposed approaches rely on sampling strategies: candidate grasps are generated according to some criteria and then ranked with some quality metric. Uniform sampling around heuristic pre-grasps [1], [2], simulated annealing ...

This note builds on an earlier Warta (Doust, 2022) that summarised the geological development of island Trinidad and margins Caribbean Sea. Parts Southeast Asia can be readily compared to these areas and, I believe, two provinces provide valuable analogues for each other. illustrate this by considering examples tectonic style taken from transpressional fold belts in eastern Java, evolution fore...

Multi-contact motion is important for humanoid robots to work in various environments. We propose a centroidal online trajectory generation and stabilization control dynamic multi-contact motion. The proposed method features the drastic reduction of computational cost by using preview instead conventional model predictive that considers constraints all sample times. By combining with state feed...