Force Feedback Actuators: Introduction and Basic References

What is Force Feedback? What kind of devices can be used to provide Force Feedback? What kinds of actuators are used in these devices? Why is Force Feedback useful?

Haptic feedback can be defined as any feedback based on tactile and kinesthetic sensations. The two main sub-categories of haptic feedback are force feedback and tactile feedback. Whereas tactile feedback “aims to stimulate tactile receptors (basically, mechanoreceptors) distributed over the skin” (Miranda/Wanderley, 2006), force feedback “aims at creating forces to be sensed by the kinesthetic receptors in muscles and tendons” (Miranda/Wanderley, 2006),

Force feedback is very useful for both musical and non-musical applications. As such, several force feedback devices have been developed which come in a variety of specifications, each with its own set of benefits and drawbacks. Examples of common force feedback devices include game controllers, joysticks, force feedback stylus-based devices, such as the Phantom Desktop, by SensAble Technologies, and force feedback paddles, such as the haptic paddle designed at Stanford University.

A variety of actuators are used to provide the mechanical output force associated with force feedback devices. Typical force feedback actuators include motors of various shapes and sizes that provide a wide range of output power. Several force feedback devices use commercially available actuators, however, it is often the case that an actuator will be designed to specifically meet the need of a given application.

In terms of musical applications, force feedback is very useful, specifically in the design of haptic music controllers: controllers that display active haptic feedback. The relationship between the feel of an instrument/the force feedback onto the user and the overall playability of the instrument /the way in which the instrument sounds is a major area of research that has been/still remains to be explored in the future. The choice of actuator/the design of new actuators to be used to provide the user with force feedback in new haptic music interfaces is also an active area of research. (Miranda/Wanderley)

Various papers and PhD theses have researched the integration of haptic feedback for various application. More recently, researchers have started exploring the importance of haptic feedback in relation to music, specifically, in the design of digital musical instruments.

To start with:

• Two papers by Vincent Hayward, namely, Do it yourself Haptics : part 1 and Do it yourself Haptics : part 2 provide a good starting point and researchers who are new to working with haptic devices.

• Edgar Berdahl's PhD thesis, Applications of Feedback Control to Musical Instrument Design provides an in depth look into haptic devices, actuators used in these devices and their application to the design of musical instruments. Additionally this thesis provides some excellent references regarding the psychology and perception of touch.

• The book New Digital Musical Instruments: Control and Interaction Beyond the Keyboard. by Miranda, E. R., and M. M. Wanderley.“ also provides useful information about force feedback systems, the actuators used in these devices etc

• Another paper by Vincent Hayward, Haptic Interfaces and Devices, provides a excellent reference to the various devices used in haptic feedback systems.

• Åström, K.J., and R. M. Murray. 2008. “Feedback Systems: An Introduction for Scientists and Engineers.” Princeton University Press.

• Burdea, G. 1996. “Force and Touch Feedback for Virtual Reality”. Wiley-Interscience. New York, NY.

• Cadoz, C., et al. 2003. “ACROE-ICA. Artistic Creation and Computer Interactive Multisensory Simulation Force Feedback Gesture Transducers.”, In Proceedings of the 2003 International Conference on New Interfaces for Musical Expression - NIME03. pp. 235-246.

• Florens, J.L. et al. “ERGOS: Multi- degrees of Freedom and Versatile Force-Feedback Panoply.” In Proceedings of EuroHaptics’04. Munchen, Germany, pp. 356-360.

• Hayward, V., and O.R. Astley. 1996. “Performance Measures for Haptic Interfaces.” In Robotics Research: The 7th International Symposium. Giralt, G., Hirzinger, G., (Eds.), Springer Verlag. pp. 195-207.

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

• Massie, T.H., and J. K. Salisbury. 1994. ‘‘The PHANToM haptic interface: A device for probing virtual objects.’’ In Proceedings of the ASME IMECE Symp. Haptic Interfaces for Virtual Environments and Teleoperator Systems. 55(1): 295–299.

• Sinclair, S. 2007. Force-Feedback Hand Controllers for Musical Interaction. Masters Thesis. McGill University.

• Bibliography