of the mass the active device may comprise a shape memory alloy actuator or any other mechanism capable of controlling the position of the mass fig1 shows how the electrical and mechanical signals propagate through the tactile feedback control system in a preferred embodiment of the invention the embodiment shown employs a d c servo motor 1701 as the mass moving actuator of a vibrotactile unit a computer 1707 or other signal processing means sends a digital value representing the desired actuation level control signal to the digital to analog convert d a 1703 the analog output of the d a is then amplified by a variable gain amplifier 1704 to produce an analog voltage activation signal this voltage is placed across the servo motor driving the motor at a desired angular velocity the voltage signal may alternately be converted to a current activation signal for driving the motor at a desired torque velocity damping of the servo control loop may be performed by tachometer feedback not shown the computer 1707 digital to analog converter 1703 analog to digital converter a d 1702 bus 1709 and variable gain amplifier 1704 may be elements of a signal processor digitized values from a d 1702 from analog joint.