Magnetic actuation of a micro-diaphragm structure for an active tactile sensor

We previously proposed an active tactile sensor that detects both the contact force and hardness of objects such as fingertips. We validated the device principle by using a pneumatic actuation system [1-2]. As a new method for driving the sensor element, we proposed the idea of using a magnetic force working between a permanent magnet on the sensor element and a microfabricated flat coil. We developed the flat coil by using thick photoresist as a mold and electroplated copper as a conductor. We assembled the sensor element and the flat coil, and constructed a hybrid active tactile sensor system. When we dynamically drove the sensor with the magnetic actuator, we could drive the sensor element around its mechanical resonance frequency. We expect that this active tactile sensor can detect a variety of information about an object, such as its hardness and damping factor.