Patent ID: 8739618

Claim:
An apparatus for determining a deformation speed V that is a rate of change of an amount of elastic deformation of an elastic member that connects a driving element and a driven element to be actuated, the deformation speed V being determined based upon quantized values of the amount of elastic deformation, the apparatus comprising: a driving speed acquisition unit configured to acquire a driving speed Vd that is a speed at a driving force input point at which a driving force from the driving element is transmitted to the elastic member; a deformation amount acquisition unit configured to acquire an amount of elastic deformation Pe of the elastic member as a quantized value; an approximate rate computation unit configured to compute an approximate rate Ve based upon a plurality of values of the amount of elastic deformation Pe acquired at different points in time by the deformation amount acquisition unit, the approximate rate Ve being a rate of change of the amount of elastic deformation Pe obtained by smoothing out an abrupt change in the values of the amount of elastic deformation Pe caused to appear by quantization; and a deformation speed computation unit configured to compute the deformation speed V of the elastic member based upon the driving speed Vd acquired by the driving speed acquisition unit and the approximate rate Ve computed by the approximate rate computation unit, by the following formula: V=A ·( −Vd )+ B·Ve where A is a coefficient increasing with increase in frequency of fluctuations in a position of the driving force input point, and B is a coefficient increasing with decrease in the frequency of fluctuations in the position of the driving force input point.