Though touching a speaker cone does provide a sort of haptic feedback, there are some serious problems with the efficacy of this method. For any other actuator application it becomes necessary to filter, transpose and direct haptic signals.

Actuator software mediates between abstract signals (say, a hard surface in a virtual space, or the audio portion of a haptic symphony) and physical actuators. It is often necessary, as actuators require very different types of signals than other transducers.

Actuator control in an engineering realm is part of PID control theory. Various methods of implementing PID (proportional, integral, derivative) control are listed here, in the bibliography and web resource sections.

Review other pages on this wiki for idiosyncrasies of actuator responses and the human response to haptic feedback, for it is the union of these two realms that makes actuator software necessary.

A variety of software is used to design, control and test actuator based devices. This page is a dedicated introduction to their use.

Haptic feedback has received systematically less attention among scholars than gestural acquisition/synthesis for digital musical instruments. Actuator software, in turn, has been even less closely regarded in musical realms. More recently (as in the past 5 years), researchers have started recognizing the importance of haptic feedback in a music context, and as a result have created some software specifically for the control of actuators.

To start with:

• First, Typology of Tactile Sounds and their Synthesis in Gesture-Driven Computer Music Performance (2000) by Joseph Rovan and Vincent Hayward describes the fundamental problems of actuator software in a musical context. Should familiarize the reader with challenges in this field.

• Solutions to the above issues are put forth in Do It Yourself Haptics: Parts 1 & 2 by Vincent Hayward. These papers contain a great introduction to haptic feedback in a musical context in general. Hayward summarizes the software necessary for several different musical actuator applications.

• Cutaneous Grooves: Composing for the Sense of Touch by Eric Gunther and Sile O’Modhrain (2003) describes a simple solution to the actuator software problem using Pro Tools.

• Most great resources in this field exist outside of the musical realm, as engineers have been interfacing with actuators in slightly different contexts for decades. The book Programmable Controllers: Theory and Implementation (Second Edition) by L.A. and E.A. Bryan contains a solid introduction to PID control theory, and is available online (see Internet directory)

• Sinclair, S., Wanderley M. M., 2008. “A run-time programmable simulator to enable multi-modal interaction with rigid-body systems.” Interacting with Computers. 21, (2009) pp 54-63

• Tao G., and P.V. Kokotovic. 1996. “Adaptive Control of Systems with Actuator and Sensor Nonlinearities.” John Wiley and Sons, New York.

• Howard, D. M., S. Rimell, and A. D. Hunt. 2003. “Force Feedback Gesture Controlled Physical Modeling Synthesis.”, In Proceedings of NIME03, pp. 95-98.

• M. Solveson, M. Christini, D. Collins, “Actuator Design: Meeting your Customer's Requirements for Success”, Ansoft, LLC, 2008.

• Guda V. and W. Semke. 2007. “A Precision Positioning Actuator System using a PID Controller.” Society for Experimental Mechanics, Inc.

• Bibliography