This paper proposes a model reference tracking based adaptive PID controller with adaptive mechanisms in both feedforward and feedback paths. The objective is to force the outputs of a not explicitly known multiple input multiple output (MIMO) linear time-invariant system to track the outputs of a known reference model. A PID controller is inserted to the feedback path. The parameters of the PID controller are computed adaptively by eliminating output tracking errors. This approach allows us to manipulate the multiple motions of a complicated, unstable, or highorder robot by operating on a simpler, stable, or lower-order known reference model. The mathematic description of the robot is not required. Output matching and tracking conditions are derived and analyzed.