Abstract: An improved method of sensing strain allows measurements of stress, torque, vibration and other loads imposed on a body without physical contact between the body/sensor and the monitoring equipment. An induction loop is at least partially comprised of a magnetostrictive material with a non-linear current-voltage relationship. An excitation device such as a coil is used to induce an AC response in the sensor. The non-linear response to the induced current is received by a sensing device such as a sensing coil, and the output thereof is filtered. The excitation device and sensing device are located in operative proximity to the sensor, but need not be in contact therewith, allowing easy measurement in small spaces, under harsh conditions, or of moving bodies such as drive shafts. The non-linear response of the sensor induces easily detectable harmonics of the base frequency of excitation. These harmonics may advantageously be measured as well.

Abstract: A thermal control device for controlling the temperature of a craft/spacecraft is an electrostatic switch causing a large change in apparent emissivity. A flexible covering has a high emissivity and makes close contact with the surface of the spacecraft when electrostatically attracted thereto, when the covering is out of contact, the spacecraft surface emissivity controls radiation. The device can operate with moderate levels of DC voltages. Application of voltage results in high emissivity while removal of voltage allows a separator to move the covering out of contact and thus results in low emissivity.

Abstract: An improved method of sensing strain allows measurements of stress, torque, vibration and other loads imposed on a body without physical contact between the body/sensor and the monitoring equipment. An induction loop is at least partially comprised of a magnetostrictive material with a non-linear current-voltage relationship. An excitation device such as a coil is used to induce an AC response in the sensor. The non-linear response to the induced current is received by a sensing device such as a sensing coil, and the output thereof is filtered. The excitation device and sensing device are located in operative proximity to the sensor, but need not be in contact therewith, allowing easy measurement in small spaces, under harsh conditions, or of moving bodies such as drive shafts.

Abstract: A method of sensing strain in a material includes the steps of embedding in a material at least one wire formed of a conductive core and a magnetoelastic film coated around the conductive core and having a known level of saturation, interconnecting an input lead to one end portion of the wire and an output lead to another end portion of the wire, inputting an electrical current in the wire through the input lead so as to drive the magnetoelastic film of the wire to saturation such that the electrical impedance is sensitive to changes in strain in the material, and outputting an electrical signal from the output lead being proportional to a strain imposed on the material surrounding the wire.

Abstract: A thermal control device for controlling the temperature of a craft/spacecraft by means of an electrostatic switch to change the mode of heat transfer of the craft/spacecraft skin from conduction to radiation. The change is by means of a large change in apparent emissivity. The device can operate with moderate levels of DC voltages. Application of voltage results in high emissivity while removal of voltage results in low emissivity.