Developing a novel soft magnetic force sensor based on Hall Effect

This paper proposes a new inexpensive soft force sensor suitable for soft robotics applications that require high flexibility and wide range of sensing area. All Hall Effect sensors developed so far use a Hall Effect sensor to detect the magnetic field of a piece of solid magnet. The proposed force sensor in this paper uses a Hall Effect sensor to detect the magnetic flux density change induced by aligned magnetic powder blended with silicone rubber when a normal force is applied. The sensor is designed and tested with different magnetic powder density and sensor dimensions to achieve an optimum design in sensitivity as well as linearity. The experimental results show that different force measurement range with specific desired sensitivity can be achieved by adjusting certain physical properties of the sensor. This is a useful feature for lots of soft sensing elements in today's applications requiring more compliance and reliable sensors, especially in soft robotics applications.