Grasping Force Control for a Robotic Hand by Slip Detection Using Developed Micro Laser Doppler Velocimeter

Area of Science:

• Robotics
• Sensor Technology
• Mechatronics

Background:

• Laser Doppler Velocimetry (LDV) is a high-response surface velocity sensor.
• LDV's potential for slip detection in grasping is hindered by its large size.
• No prior reports exist on using LDV as a slip sensor for robotic manipulation.

Purpose of the Study:

• To demonstrate the feasibility of grasping force control using a micro-LDV.
• To develop a compact LDV for robotic fingertip integration.
• To validate the μ-LDV's capability in detecting object slip during grasping.

Main Methods:

• Developed a micro-LDV (μ-LDV) using MEMS fabrication processes to reduce size.
• Integrated the μ-LDV onto a robotic fingertip as a slip sensor.
• Performed grasping force control experiments with aluminum, wood, and acrylic blocks.

Main Results:

• Successfully demonstrated grasping force control for diverse materials (aluminum, wood, acrylic).
• Validated the μ-LDV's effectiveness in detecting slip without grasping force feedback.
• Achieved precise control by utilizing μ-LDV signals to discriminate slipping.

Conclusions:

• The developed μ-LDV is a feasible and promising slip sensor for grasping force control.
• Micro-LDV technology overcomes size limitations for robotic applications.
• This sensor enables advanced robotic manipulation and object handling.