The armwrestling match between an EAP actuated robotic arm and a human
High Resolution image of the armwrestling
match graphics (TIFF (10.1 MB))
In 1999, Dr. Yoseph
Bar-Cohen, JPL, posed a scientific challenge to the worldwide research and
engineering community to develop a robotic arm that is actuated by artificial muscles
(moniker for electroactive polymers (EAP)) to win a wrestling match against a
human opponent.
Objective
Promote
advances towards making EAP actuators that are superior to the performance of
human muscles
Increase
the worldwide visibility and recognition of EAP materials
Attract
interest among potential sponsors and users
Lead to
general public awareness since it is hoped that they will be the end users and
beneficiaries in many areas including medical, commercial, etc.
Initially,
the challenge is to win against a human (any human) using a simple shape arm
and this recent competition was against a high school student who represented
the human side.
The
ultimate goal is to win against the strongest human using as close resemblance
of the human arm as possible.
Developing a winning arm will require advances in the EAP field infrastructure
including: Analytical tools, materials science, electromechanical tools,
sensors, control, feedback, rapid response, larger actuation forces, actuator
scalability (use of small and large ones), enhanced actuation efficiency, etc.
2008 - The EAP Armwrestling Contest
The intent of the armwrestling contest is to challenge and
encourage advances in development of EAP materials. As progress is being
in the field of EAP "the bar will be raised" on the challenge so that
eventually the competing arms will need to act very similar to a human
arm. Therefore, in future wrestling contests during the SPIE’s EAP-in-Action
Session only the following definition for EAP will be accepted for the
actuators that will drive the participating wrestling arms.
EAP is only a material or combination of materials that is
primarily composed of a polymer that convert(s) electric to mechanical energy
for which the presence of the polymer is a key to the generated force and
displacement. The response should be reversible, namely, the actuated
robotic arm should be able to use the same actuation mechanism to return to the
starting position.
- No actuators that involve
input of gases, liquids or chemicals will be accepted (e.g., actuated by
pneumatic, hydraulic, or use of acid/base).
- An exception will be given to the use of polymers that
are indirectly driven by electric current or field but they will
need to be identified as being so. For example, thermally actuated
polymer materials will be accepted if they use embedded electrical heating
elements.
2007 – No EAP robotic arms are ready to wrestle
2006 - The EAP Armwrestling Contest
The 2006 competition was held during the SPIE’s EAPAD Conf. on Feb. 27, 2006 at 5:00 PM and involved measuring the arms capability and comparing the data of the competing arms. Each competing EAP actuated arm pulled on a cable that has a force gauge on its other end and was supported by the wrestling fixture (see Figure 1). A schematic diagram with the fixture dimensions is shown on the right of Figure 1. This fixture was strapped to the table (see Figure 2) and the EAP actuated arms were tested for speed and pulling force capability. To simulate a wrestling action a 0.5-kg weight that was mounted on the cable had to be lifted to the top of the fixture (shown in the photo – see Figure 1) and the time to reach the top was measured. In case the arms could not lift the weight to the full height of 9.78” an adjustable base was used to place the weight at a higher starting level.
FIGURE 1: Photos and drawing of the fixture that was used to test the force and speed of the EAP actuated robotic arms
FIGURE 2: An example of the table that will be used to support the test fixture. The table dimensions are: Length: 244 cm (96") x Width: 76 cm (30") x Height: 76 cm (30") and Thickness: 2.5 cm (1").
Upon pulling on the cable the time was gauged to determine the speed and once the weight reached the top, the cable was stretched and the force was measured by the gauge. To establish a baseline for performance comparison, Panna Felsen’s capability was the first to be measured and then the three participating robotic arms were tested. The rules of the contest are on http://ndeaa.jpl.nasa.gov/nasa-nde/lommas/eap/amerah/Amerah-2006/armwrestling-rules.htm The results of the contest this year were as follows (the participants are listed below the table):
|
|
Lifted height |
Force (lbf) |
Speed (in/sec) |
Notes |
|
Panna Felsen |
9.78" |
21.8 |
>9.78 |
BASELINE |
|
VT - |
~8.78" (started from bottom level) |
0.2 |
~0.037 |
Strongest |
|
ERI (Shahinpoor) |
~3.28" (started from 6” height) |
0.2 |
~0.045 |
Fastest |
|
VT - Mech. |
Upon activation actuators failure occurred |
|||
1.
Environmental Robots Incorporated (ERI),
2. Virginia
Tech, USA: : Senior Students under the lead of Barbar
Akle, Nakhiah Goulbourne and Don Leo at the Mechanical Engineering
Department, including Jaime Schmieg (Team Leader),
Dave Griffiths, Heath Folmsbee, Anthony Ribaudo, Erin Lucas, Charley Sessoms
and Josh Leong. This group used
dielectric 
elastomer EAP for the actuation of the arm.
3. Virginia Tech, USA: : Senior Students under the lead of John Cotton at the Department of Engineering Science and Mechanics, including Joseph Ash, Matthew Degner, Sara Jasin, Jordan Milford, Kevin Nash, Josh Oechslin (Team Leader), Catherine Ross, and Brandon Shue. This arm was based on the same mechanism that was used by the VT students in 2005.
Acknowledgement
The wrestling fixture (Figure 1) was drawn by Ayoola K Olorunsola, JPL, constructed by Qibing Pie and his students from UCLA, and finalized by Chris Jones, JPL.
Considering participation in the 2007 armwrestling
contest
1. DSO
National Laboratories, Defense Medical & Environmental Research Institute,
Centre for Human Performance,
2. Swiss Federal
Laboratories for Materials Testing and Research, EMPA,
2005 - The EAP/Human Armwrestling Match
The first competition was held on March 7, 2005 at 5:00 PM
in
1. Environmental Robots
Incorporated (ERI),
2. Swiss Federal
Laboratories for Materials Testing and Research, EMPA,
3. Virginia Tech - Steven Deso, Stephen Ros, Noah P. Papas,
Senior Students in the Engineering Science and Mechanics Dept.
The longest to hold against the student has been
the arm from ERI and it lasted for 26-seconds. To get a prospective to this
major milestone for the field of EAP one may want to be aware that the first
flight of the Wright Brothers before over hundred years lasted only 12-seconds.
The following photos of the three arms where taken during the competition: 
Also, a video of
the competition is available on the Discovery
channel's Daily Planet, March 15, 2005.
Current status
The first
Armwrestling Match of EAP Robotic Arm against Human (AMERAH) was held on March
7, 2005 at 5:00 PM during the International Society for Optical Engineering
(SPIE) Annual International EAPAD
(EAP Actuators & Devices) Conference.
The 1st
AMERAH was coordinated with the United
States ArmSports.
On March
15, 2004, John Brzenk (the World Wrestling Champion
per Guinness Book of Records), John Woolsey (ABC Wide World of Sports
Wrist-wrestling Champion) and Harold Ryden
(California State Champion) attended the EAP-in-Action Session and they were
introduced to the EAPAD Conference attendees to give them an idea about the
toughness of this challenge. These Champions participation was arranged thanks
to Mr. Marvin Alex Cohen, who was the Technical Advisor to Warner Bros Motion Pictures
in the movie "Over The Top" that is stared by Sylvester Stallone. Mr.
Cohen participated under the banner "Fox Sports Net".
RULES for the Armwrestling competition in 2005 - A website was formed
for the AMERAH
Armwrestling Competition Rules.
The Human Opponent
The human opponent was Panna
Felsen, who is a straight A high school student
from the
The Table for the Armwrestling Competition
A standard Armwrestling table was brought to the competition by Dave Devoto who is a pioneer and leading representative of the United States ArmSports
AMERAH Competition Judges
The following are the members of the AMERAH organization
Committee and the Competition Judges.
CHAIR: Yoseph Bar-Cohen, Senior
Research Scientist and Group Leader, JPL's
NDEAA Lab.
Dave Devoto - Pioneer and leading
representative of the United
States ArmSports
Richard Landon - from Stan Winston Studio (SWS designed and
created the robots and makeups for Spielbergs movie AI). Mr. Landon wrote chapter 6 in
the Biologically
Inspired Intelligent Robots book
John D. Madden -Univ. of British Columbia
(Canada), Co-chair of the 2005 EAPAD Conference
Joanne Pransky - World's First Robotic
Psychiatrist www.robot.md
Brian Thomas - Senior Event Manager, SPIE-- The International Society for Optical
Engineering
The Armwrestling - Support Organizations
The hosting and logistics of the competition was done by SPIE as part of the EAP-in-Action Session of the
annual EAPAD Conference, San Diego, CA, USA
The United States ArmSports
is an umbrella organization representing armwrestlers,
armwrestling organizations and tournaments in the United States of America and
around the World. ArmSports is a relatively new term
encompassing the ancient sport known as Armwrestling, Arm Wrestling,
Arm-Wrestling, Wrist-wrestling, Indian wrestling etc. United States ArmSports is the exclusive American member of the World
Armwrestling Federation (WAF).
To return to:
NDEAA Webhub or to the
WorldWide Electroactive Polymers (WW-EAP) Webhub