Abstract: A dry electrode, which is a single-plate capacitor, is particularly adapted to be placed on a patient's scalp to detect brain waves in an EEG system. The electrode comprises a metal disk sandwiched between very thin and relatively thicker layers of ceramic. The metal disk is attached to a small disk printed circuit board that carries an amplifier to amplify the brain waves detected by the electrode. The quality of contact of the electrode with the patient is measured by applying a pulse or voltage step through the ground electrode.

Abstract: The present invetion involves a tolerance based motion controller. The controller is capable of processing a group of tolerance constraints. The tolerance constraints specify where and when each tolerance constraint is to be applied, along with the information specifying the desired trajectory of motion. There are also a group of velocity constraints, specifying the maximum allowable velocity at each point along the desired trajectory. This information along with sensor feedback is used to modify the velocity along the actual trajectory of motion. This results in the time required traverse the trajectory being as short as possible. Also, the actual trajectory of motion should never exceed the permissible deviation from the desired trajectory, as specified by the tolerance constraints, with the velocity always being bounded by the specified velocity constraint.