A 1 DOF model of force control is considered with discrete delayed feedback. The act and wait control concept is introduced as a special case of periodic control: the feedback gain is constant for a sampling period (act), then it is zero for a certain number of periods (wait), then it is constant again, etc. It is shown that by applying the act and wait concept, the stability properties of the system improve and the force error caused by the Coulomb friction decreases. If the period of gain variation is larger than the feedback delay, then the system performance changes radically: the stability properties improve significantly, and the optimal control parameters can provide dead beat control. This way, by using the act and wait concept, the delay effects are eliminated from the system.

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