Virtual Point Method Research Articles

Virtual Point Control for Step-Down Perturbations and Downhill Slopes in Bipedal Running.

Bipedal running is a difficult task to realize in robots, since the trunk is underactuated and control is limited by intermittent ground contacts. Stabilizing the trunk becomes even more challenging if the terrain is uneven and causes perturbations. One bio-inspired method to achieve postural stability is the virtual point (VP) control, which is able to generate natural motion. However, so far it has only been studied for level running. In this work, we investigate whether the VP control method can accommodate single step-down perturbations and downhill terrains. We provide guidelines on the model and controller parameterizations for handling varying terrain conditions. Next, we show that the VP method is able to stabilize single step-down perturbations up to 40 cm, and downhill grades up to 20–40° corresponding to running speeds of 2–5 ms−1. Our results show that the VP approach leads to asymmetrically bounded ground reaction forces for downhill running, unlike the commonly-used symmetric friction cone constraints. Overall, VP control is a promising candidate for terrain-adaptive running control of bipedal robots.

Numerical Simulation of 1-D and 2-D Continuous Geo-electrical Magnetotelluric Forward

Finite element technology in one-dimensional layered media of the continuous electro-media and the two-dimensional continuous electrical is displayed in ways of the special matrix equations in the variation formula and split technical conditions. To achieve a one-dimensional layered continuous electrical finite element numerical simulation of the media, the introduction of the secondary triangulation rectangular subdivision has been used to the two-dimensional numerical simulation, and using the rectangular center to set up the virtual point method to reduce the computational workload in calculation. Then design a meaningful manner electric model, the base power model analysis of electromagnetic waves in the rock, they all provide the guidance for the actual production. DOI: http://dx.doi.org/10.11591/telkomnika.v11i6.2717