Mid-air haptic generation analytic techniques

Abstract

Mid-air ultrasonic haptic devices operate by manipulating an acoustic field to produce a haptic effect on a user. Addressing mid-air haptic devices which abstracts the most basic acoustic fundamental from that of a point to a 'primitive' provides tools to adjust shape, location, and amplitude. A primitive can be designed to provide a haptic effect at the location targeted, removing the requirement of the designer needing to understand methods to create a haptic sensation. Further, a control scheme for a set of dynamic acoustic phased-array solvers is presented which enables a distributed system to compensate for unwanted time-of-flight artifacts at low cost. This is achieved by recursively subdividing the system into subtrees of phased-array nodes whose output can be estimated and the desired field drive distributed amongst the nodes. Timings of the desired field drive requests submitted to individual phased-array node inputs are then modified to compensate for the differences between wave coalescence/convergence and wave emission times, the time-of-flight, resulting in a more accurate acoustic field.