Feed-back accelerometer circuits with a velocity output

Abstract

Circuits are suggested for modifying the feed-back loop of an accelerometer so that the output voltage is proportional to velocity, that is, an integrating process is incorporated within the loop. The main advantage is that the indicated velocity should be less critical with respect to amplifier drift than in most existing methods Of integration. Circuits design is treated in some detail for typical examples of force feed-back accelerometers, including both undamped and viscous damped types, and it is shown that acceptable accuracy and stability should be possible with either type. A comparison is made with other methods of integration, and it is concluded that the method may find application, for example, as part of an analogue inertial navigation system, but that other methods are likely to be preferred in systems incorporating digital computers.