In this paper, an exoskeleton performing a sit-to-stand motion is studied. A new approach to control system design for this mechanism is proposed. Proposed control system uses information about currents in the motor's armature cores to assess how much the system is loaded and change its behavior accordingly. It also uses ZMP (zero moment point) principle for assessing system's balance. In the paper, some results of the numerical simulation are presented. On a few examples it was shown how changing duration of sit-to-stand motion influences dynamical behavior of the mechanical system.

This paper presents a footstep planning algorithm for a six-legged in-pipe robot moving in spatially curved pipes. The algorithm allows us to generate sequences of points on the pipe's inner surface where the contact pads of the robot should come in contact with the surface. The algorithm uses mapping of the pipe onto a two-dimensional surface with a simpler geometry. The algorithm plans footstep sequences on that two-dimensional surface and then maps them back onto the pipe. It is shown that this procedure can be extended by implementing an obstacle avoidance algorithm formulated as a quadratic program.

Many of the existing motion planning algorithms require the free space to be decomposed into convex obstacle-free regions. This paper presents an algorithm for generating such regions. The algorithm is based on stereographic projection. The algorithm requires relatively simple computations, compared with some of the known methods. Three applications of the algorithm were demonstrated: motion planning for a walking robot, trajectory generation for an unmanned aerial vehicle and a motion planning for an in-pipe robot.

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