Tactile sensing is essential for intelligent robot control such as for dexterous manipulation tasks. To provide reliable sensors that can withstand industrial applications, we have developed a soft and thin-film tactile sensor capable of detecting tri-axis force components including normal and shear forces. The thickness of the sensor is 5.5 mm, and the sensor can be easily attached on an end-effector. Two layers of capacitive sensing-electrode arrays sandwiching an elastomer layer of 2-mm spatial resolution are embedded in soft material, and output signals are distributed. To measure the external force vector, center-of-distributed-signal calculation was conducted. Our sensor exhibited linear behavior within 0.1 to 10 N for normal force and 0.1 to 4 N for shear force. With high reliability, sensor sensitivity did not change over ±10.0% even after one million repetitive keystroke cycles and one million repetitive shear movement cycles. To determine the sensor’s effectiveness for manipulation tasks, a grasping-force control experiment was conducted using sensor signal feedback, and multiple local-shear force vectors were successfully calculated sing area-divided methods.
