Min-Max Optimal Control of Robot Manipulators Affected by Sensor Faults.

This paper is concerned with the control law synthesis for robot manipulators, which guarantees that the effect of the sensor faults is kept under a permissible level, and ensures the stability of the closed-loop system. Based on Lyapunov's stability analysis, the conditions that enable the application of the simple bisection method in the optimization procedure were derived. The control law, with certain properties that make the construction of the Lyapunov function much easier-and, thus, the determination of stability conditions-was considered.

Two-axis goniometer for single-crystal nuclear magnetic resonance measurements.

We report the design and construction of a two-axis goniometer capable of any sample orientation with respect to the external magnetic field. The advantage of this design is that it allows free rotations around a single axis independent of the other which minimizes rotational error without reduction of the angle range. Goniometer is capable of operating with high precision at both low and high temperatures and in high magnetic fields.