Haptic perception of force

This article reviews research that deals with measuring the precision and/or the accuracy of haptic force perception, using psychophysical methods. Other aspects of force perception might include physiological aspects or neuronal processing, but these are beyond the scope of the present article. Furthermore, force sensation plays a role in the perception of other physical aspects, such as friction or stiffness. These aspects are reviewed separately elsewhere. \u3cbr/\u3e\u3cbr/\u3eForce perception relates to two aspects of force: its magnitude and its direction. Perception of these aspects is discussed separately below. Concerning force magnitude, many early studies have focused on the perception of force in the direction of gravity, i.e. the weight of objects. This is discussed first. Then, force magnitude perception in other directions is discussed. Finally, some applications of this research are discussed. \u3cbr/\u3e\u3cbr/\u3eDifferent psychophysical techniques have been used to study force perception. To study the relationship between physical and perceived force magnitude, the technique of magnitude estimation has been used. To measure the smallest difference in force magnitude or direction that can be perceived, discrimination experiments have been performed. Finally, to study the relationship between force magnitudes perceived in different ways, or between physical and perceived force direction, matching experiments were done. This subdivision is used to categorise the different studies. \u3cbr/\u3