The finger-device interaction has been an area of interest among researchers in haptics. Due to the dependence of friction force and friction coefficient on the normal load, it is essential to maintain a controlled constant normal load when studying the effect of other parameters including humidity and surface texture on friction. A typical practice is to use visual feedback to control the normal load. In our work, a novel reciprocating tribometer was designed that can control the normal load using a precision vertical stage. A control algorithm was developed and optimized to drive the vertical stage based on the feedback from the force transducers. Comparison between the presented tribometer and visual feedback normal force control showed that the tribometer could achieve a normal load with a standard deviation of 7.5% - 18.7%, whereas the standard deviation of visual feedback based normal load control is measured to be 16.3% - 33.1%.
|Title of host publication||STLE 2019 Tribology Frontier Conference|
|Publication status||Published - 2019|