Extendable Palm Device

1. Overview

The extendable palm device is a robotic end-effector that can be retrofitted onto existing robotic grippers. It is constructed as a parallel mechanism that can produce a striaght line motion for the palm while avoiding collisions with the base gripper as can be seen in the videos above. Our 3D-printed prototype is acutated by one Dynamixel AX-12A servo motor connected with a simple gear train. For reproduction of the extendable palm device, please refer to the bill of materials and the link for the Solidworks model made available below.

Related Patents:

• C. H. Kim and J. Seo, "System and Methods for Robotic Precision Placement and Insertion," US Patent Application, Filed May 11, 2020.

Related Articles:

• C. H. Kim and J. Seo, "Dexterous Ungrasping: Methods and Designs for Secure Placement and Insertion through Dexterous Manipulation," (Under preparation).

Contributers: Chung Hee Kim, Jungwon Seo

2. Bill of Materials

Solidworks Model:

• Version 1.0.0 (25 May 2020)

3D-Printing Parts

1. Bracket (Top) x 1
2. Bracket (Bottom) x 1
3. Proximal Link (Left) x 1
4. Proximal Link (Right) x 1
5. Distal Link x 2
6. End-effector Link x 1
7. Gear Connector x 1

Actuator

• Dynamixel AX-12A servor motor: Actuator software available here.

Gear parts

• Lego Technic Gear, 28 tooth double bevel x 2
• Lego Technic Gear, 20 tooth double bevel x 1

Fasteners

• Metric M4 x 30mm socket head cap screw (x4)
• Metric M4 x 15mm socket head cap screw (x4)
• Metric M3 x 15mm socket head cap screw (x2)
• Metric M2 x 40mm socket head cap screw (x2)
• Metric M4 nuts (x4)
• Metric M2 nuts (x2)

3. Assembly Diagram

Note: The Dynamixel AX12-A servo motor and the wrist bracket is connected via the Robotis FP04-F3 side mounting frame bracket that comes with the servo motor purchase.

4. Power and Signal

5. Maintenance

For any technical issues, please contact John Kim chkimaa@connect.ust.hk.