Patent ID: 8757716

Claim:
A motion sensing apparatus for a moving child support device, said motion sensing apparatus comprising: a housing defining a longitudinal axis; at least one piezoelectric sensor having a sensing surface positioned within the housing; a weighted member positioned within the housing and configured for movement in the direction of the housing's longitudinal axis; and a signal amplifier; wherein the weighted member is configured to apply a variable force to the sensing surface of the piezoelectric sensor in response to movement of the motion sensing apparatus; wherein the piezoelectric sensor is configured to output a voltage signal corresponding to the magnitude of the variable force applied by the weighted member, the output voltage signal being indicative of the motion sensing apparatus's movement with respect to the housing's longitudinal axis; and wherein the signal amplifier is configured to receive the voltage signal output by the piezoelectric sensor and filter the voltage signal in order to output a motion signal indicative of the frequency of the motion sensing apparatus's oscillation with respect to the housing's longitudinal axis.