Robotic Hands Mimicking the Human Hand David French
Robotic Hands Mimicking the Human Hand David French April 24, 2013
Types • Prosthetic Image Courtesy of Luke Skywalker http: //www. scifi-review. net/teenager-gets-a-bionic-hand-that-luke-skywalker-would-envy. html
Types • Non-Prosthetic http: //www. vrealities. com/shadowhand. html
Applications • Prosthetic • Humanoid robots • Variety of small-scale dexterous operations – Working in inaccessible or hazardous environments, e. g. radiation, chemical or biological hazards, disabling IEDs • Research – Rehabilitation – Ergonomics
How It Relates to Our Course • Doesn’t usually use inverse kin, differential kin, or trajectory generation since the joints are usually controlled in manually mode. • Motors are sized based on desired torques/speeds, and are very constrained by physical size. • Up to 20 DOF, multiple independent kinematic branches (e. g. fingers)
Examples http: //blogredbox. blogspot. com/2011/09/geeky-gadgetsnewsletter_22. html
Shadow Hand • Shadow Hand – comparable to a human hand in size and shape, and reproduces all of its DOF – 24 joints altogether, with 20 DOF – Not as strong as a real human hand You. Tube link
Shadow Hand • Available in both electric motor and pneumatic muscle driven models – 20 motors or Air Muscles • Every joint has a Hall effect sensor for positional feedback • Every actuator has a force/pressure sensor • Can add third-party tactile sensors • $100 K - $250 K total cost
Shadow Hand First, Middle, Ring finger 1 Distal - Middle 2 Middle - Proximal 3 Proximal - Knuckle 4 Knuckle - Palm Little Finger 1 Distal - Middle 2 Middle - Proximal 3 Proximal - Knuckle 4 Knuckle - Metacarpal 5 Metacarpal - Palm http: //www. vrealities. com/shadowhand. html Thumb 1 2 3 4 5 Distal - Middle - Proximal 1 Middle - Proximal 2 Proximal - Palm 1 Proximal - Palm 2 Wrist 1 2 Palm - Wrist - Forearm
Shadow Hand • Controlled with a 22 sensor Cyber. Glove
Shadow Hand • Integration with Bio. Tac tactile sensor – – forces micro-vibrations temperature estimate radius of curvature of a contacted object – discriminate edges, corners, and flat surfaces – detect slip – discriminate objects based on their texture, compliance, and thermal properties
Sandia Hand You. Tube Link • Affordable: $10 K • Mostly produced with parts found in cellphones • Digits attach to palm using magnets • Can replace its own fingers http: //www. popsci. com/technology/article/2012 -08/video-robot-hand-runs-cellphone-parts-can-replace -its-own-digits
Stanford Hand Video Link • Single actuator • Equal force at all digits, regardless of configuration or shape of object • Digits bend and twist • Extremely durable http: //www. engadget. com/2012/08/04/rethinking-the-robot-hand-at-harvard-video/
DARPA Hand (Pit Crew Example) Video Link http: //www. nytimes. com/2013/03/30/science/making-robots-mimic-the-human-hand. html
SQUSE • 16 joints, 22 actuators • Flesh-toned silicone rubber skin cover You. Tube Link http: //www. popularmechanics. com/technology/engineering/robots/6 -innovative-robot-hands#slide-2
Universal Gripper • Balloon-like sack filled with coffee grounds • To pick, push gripper sack onto object, then apply vacuum to the sack Video Link http: //www. popularmechanics. com/technology/engineering/robots/6 -innovative-robot-hands#slide-5
Equipment • • Links and joints DC Motors / pneumatic motors or ‘muscles’ Position sensors Tactile (touch) and temperature sensors Controllers Microcontroller (e. g. Arduino) Software framework, e. g. Robot Operating System (ROS), which provides packages for motion, control, planning, face recognition, etc.
Controls • Neural interfaces http: //www. youtube. com/watch? v=pp. ILw. Xws. Mng
Controls • Muscle-sensing – Example: Bebionic 3 myoelectric prosthetic hand (video link) – Example: i. Limb Pulse hand prosthesis (video link) • Joystick, keyboard, mouse, other controls Bebionic 3 http: //www. dvice. com/archives/2012/ 11/luke-skywalkers. php
Controls • Position-sensing gloves http: //robotswillstealyourjob. tumblr. com/
Limitations • Limited range of motion • Limited strength/power • High cost • Manual control is often slow, if not difficult • Must be mounted on an appropriate fixture to be useful (e. g. human stub, robotic arm). • “Computer vision systems have worked only in highly structured environments on a very limited set of objects. ”[1] http: //www. nytimes. com/2013/03/30/science/making-robots-mimic-the-human-hand. html
Costs • Build your own ‘Grasping With Straws’ robot $100 -$150 http: //www. sciencebuddies. org/science-fairprojects/project_ideas/Robotics_p 003. shtml? gclid=CNm. Svp jt 3 r. YCFQ 9 e. Qgodk 1 o. ANg
Costs • Mecha. TE Robot Hand - $900
Costs • Professional-grade commercial robotic hands – Usually $10 K or much more [2] – DARPA pit crew hand: potentially $3, 000 in quantities of 1, 000 or more[2] – $10 K for Sandia Hand – $100 K - $250 K for Shadow Hand [2] http: //www. nytimes. com/2013/03/30/science/making-robots-mimic-the-human-hand. html
Practical Applications • Prosthetic • Humanoid robots • Variety of small-scale dexterous operations – Working in inaccessible or hazardous environments, e. g. radiation, chemical or biological hazards, disabling IEDs
Technical Advancements • Shadow Air Muscles – Lightweight (10 g and up) – Little stiction – Flexible • work when twisted axially or bent around corners – High power to weight ratio
Technical Advancements • Improved control interfaces, especially neural interfaces • Accuracy in mimicking the human hand • Dexterity • Modular designs • Durable designs • Greater strength-to-weight ratios • Lower cost designs
Industries Impacted • Prosthetics • Rehabilitation • Future humanoid robot applications • Hazardous/dexterous operations • Ergonomics
Questions? http: //www. 123 rf. com
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