Master-slave equipment presents a force in master side by scaling up or down the force observed in slave side. For the efficiency improvement of micro operations, etc., it is desirable that the displayed force is adjusted to the human ability to perceive.
In this paper, we deal with the scaling method considering the differential limen of the force, which is one of the inner force sense characteristics. By noticing the differential limen, the conditions for making it possible to perceive not only an existence but also a change of force are obtained. Under the condition that the differential limen is in proportion to standard stimulus, we show the condition for the perception of a change of force in master side. Simultaneously, lower limit of the scaling modulus for the perception is obtained.
We apply the conditions to the measured results and discuss the modification of the scaling coefficient when the dispersion exists in the measured values.