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Hand Arm System

Overview

Anthropomorphic light weight robot:

• Variable passive compliance in each joint
• Human like strength
• Human like range of motion
• Robust to impacts
• Potential energy storage in joints
• 3 different variable stiffness actuator (VIA) concepts
• NO torque sensors
• Fully integrated electronics
• Modular design

Degrees of freedom      Motors                        Position sensors           Weight                    Control frequency

26 52 112 13.5 kg 3 kHz

Variable Stiffness Actuators (VSA)

The Hand Arm System is equipped with 3 types of Variable Stiffness Actuators:

• Antagonism (19 DoF Hand):
  • 2 equivalent motors adjusting joint stiffness and position
  • in-tendon progressive spring mechanism
• BAVS - Bidirectional Antagonism with Variable Stiffness Actuation (2 DoF wrist,1 DoF forearm-rotation):
  • 2 equivalent motors adjusting joint stiffness and position
  • Asymmetric cam disc shape
  • Redundant joint actuation
• FSJ - Floating Spring Joint (4 DoF upper arm joints):
  • one big motor for joint positioning
  • one small motor to change the stiffness
  • one single spring

Electronics

Very high integration and power density

Units integrated in the forearm:

• 44 intelligent motor modules with integrated power inverters and 180 W peak power each
• 2 FPGA based control units
• 12 V & 5 V power supplies and distribution
• Spring deflection sensors

Units integrated in the upper arm / shoulder:

• 8 motors with up to 1 kW peak power
• Modular power inverters
• Spring deflection sensors
• Control units

Customized power supply (IGOR):

• 5 Independent 24 V & 48 V outputs with soft start and fast electronic fuse to power the complete Hand Arm System
• 4 kW peak source and sink capability
• Energy storage using supercapacitors allows operation from standard wall outlet
• Control via touch screen display or USB/RS232

VIDEOS:

Driving a Nail:
http://youtu.be/qVaaGld401I

Robustness of the fingers:
http://youtu.be/YqmRKqFqiok

The arm being hit by a baseball bat:
http://youtu.be/2JT9rD5VGvQ