Abstract: A foldable electrical wheelchair having speed and braking controls operable by an accompanying person. An H-shaped chassis supports the drive wheels, a motor unit, a shock absorber, an adjustable footrest, and a battery, and provides a low center of gravity. Arms are connected to the chassis which support the seat, back, armrests, and controls selectively in an operable, locked position, while enabling the wheelchair to be folded for storage or transportation in the trunk or body of a motor vehicle.

Abstract: Two electrical wires are connected to the surface of an electrically conductive solid body at two measurement points located on either side of a crack in the surface of the body. The two wires form a thermoelectric couple. A constant DC current is applied to the body. The two wires are connected to a device for measuring the extent of the crack and another device for measuring the temperature of the crack. By measuring the potential difference during application and interruption of the DC electric current to the body, it is possible to simultaneously obtain a measurement of the extent of the crack and a measurement of the temperature of the crack.