A Stability Analysis of Haptic Systems by Using Difference Diffrential Equation From the view point of characteristic equation

In the remote robot systems using haptic communication under communication delays, there is a problem of instability of operations or behaviors. For solving the problem, we have introduced a method using “resistance” which is proportion to the velocity and investigated the theoretical method to analyze the mechanism by using difference differential equation. However, in the former investigation, we have focused on the motion of approach to target position and mechanical howling has not been analyzed adequately. This paper shows the possibility of explanation of mechanical howling by using difference differential equation and investigates the stability condition from the view point of characteristic equation. As a result, we shew that the resistance has the effect of narrowing the stability range for approaching target position but enlarging the stability range for mechanical howling. Moreover, empirical data is examined by the method.