Multi-Degree-of-Freedom Force Sensor Incorporated into Soft Robotic Gripper for Improved Grasping Stability

Area of Science:

• Robotics
• Materials Science
• Sensor Technology

Background:

• Soft robotic grippers offer versatile object manipulation but require precise force control for delicate handling.
• Existing grippers often lack integrated, robust force sensing capabilities, limiting their application in sensitive tasks.
• Accurate force feedback is essential to prevent damage to fragile objects and avoid slippage during grasping.

Purpose of the Study:

• To develop and integrate a novel three-degree-of-freedom (3-DOF) optical force sensor into a soft robotic gripper.
• To achieve stable grasping with real-time force feedback and slip detection.
• To create a cost-effective, robust, and electromagnetically immune sensing solution for soft grippers.

Main Methods:

• Incorporation of lightweight, compact optical fibers into the soft gripper structure.
• Utilization of a contact-based light loss sensing mechanism for force measurement.
• Innervation of the gripper with optical fibers for both sensing and structural reinforcement.

Main Results:

• Demonstrated a robust 3-DOF optical force sensor with low drift (<0.1% over 9000 cycles).
• Successfully integrated the sensor into a soft pneumatic bending gripper.
• Achieved effective slip detection and grip force feedback during grasping of various objects, including magnetic materials.

Conclusions:

• The developed optical force sensor provides a stable and reliable solution for enhanced grasping stability in soft robotic grippers.
• The sensor's design is cost-effective, durable, and immune to electromagnetic interference.
• This technology enables precise force control and slip detection, crucial for handling delicate or valuable objects.