Abstract: An apparatus for and method of conducting a nerve conduction study is provided. In response to predetermined stimulation from an excitation device, a signal is generated that travels through a human body. The apparatus includes a sensing electrode operatively engagable with the human body downstream of the excitation device for sensing the signal. The apparatus further includes a pressure mounting structure operatively connected to the sensing electrode for controlling the pressure at which the sensing electrode engages the body. The pressure mounting structure includes a pressure source and a pressure sensor. A controller receives a pressure signal from the pressure sensor and the signal from the sensor electrode. The controller includes software to normalize the amplitude of the signal based on the pressure at which the sensing electrode engages the body.

Abstract: A powered transfer and transport system is provided to permit disabled individuals increased mobility and freedom of movement. The powered system performs as a wheelchair in one configuration and as a bed in another, and provides powered mechanisms for variously positioning the seating surface which are operable by the occupant from the seating surface. The powered system includes mechanisms for laterally shifting, elevating, rotating, reclining and driving the seating surface. Enhanced mobility and freedom of movement for the individual results, improving the capability for independent living and expanding employment opportunities.

Abstract: The multiple frequency impedance measurement system of the present invention permits noninvasive examination of living tissue at any one of a plurality of frequencies. Precise frequency control is provided by a phase locked loop (PLL) circuit which is adjustable among at least a plurality of frequencies by locking the loop to the output signal generated by a voltage controlled oscillator (VCO) divided by a selectable divisor. By selecting the divisor of the output signal of the VCO, the frequency is changed and, due to the use of a PLL circuit, each selected frequency is stably maintained. Electrodes connecting the circuit to tissue to be monitored are driven by a high-Q filter and buffer amplifier which convert the square wave output from a voltage controlled clipper circuit to a sine wave signal. The clipper circuit receives the output signal from the VCO and is part of a feedback loop which maintains a constant examination current for the system.