A Multifingered Robotic Hand With Fiber-Optic Force and Tactile Sensing for Remote Manipulation

Underactuated robotic hands are extensively used in remote manipulation due to their ability to adapt to various object sizes and shapes. Their structural simplicity and small number of actuators required for operation make them highly versatile and responsive, which is crucial for effective teleoperation. In addition to grasping performance, haptic feedback, which integrates force and tactile sensing, is essential for dexterous manipulation. This study proposes a solution using fiber-optic tendons embedded with fiber Bragg gratings (FBGs), combining sensing and actuation to simultaneously perform power transmission, along with force and tactile sensing. Each finger employs a fiber-optic tendon with three FBGs: one measures tendon tension, and the other two at the fingertip detect contact force and temperature. The tendon is placed on the volar side of the finger and routed to an actuation module with a servomotor at the wrist for power transmission. This tendon enables finger flexion, while a passive extension mechanism with linear springs on the dorsal side facilitates extension. Experimental results demonstrate the feasibility of this approach, showing the hand's multifunctional capabilities, including haptic feedback and power transmission, as well as its potential for teleoperation. This approach improves the robotic hand's ability to provide real-time feedback, improving dexterity in remote manipulation.