Effectiveness of cooperative and competitive shared control
- WCU Author/Contributor (non-WCU co-authors, if there are any, appear on document)
- Kevin Babecki (Creator)
- Institution
- Western Carolina University (WCU )
- Web Site: http://library.wcu.edu/
- Advisor
- Martin Tanaka
Abstract: Advances in technology place ever increasing demands for effective interactions be
tween humans and machines. Human-machine interaction (HMI) that incorporates
shared control, in which the human and machines both simultaneously in
uence the
outcome, may lead to a more natural interaction between people and machines. This
natural interaction could be particularly beneficial in assistive devices that are used
to increase, maintain, or improve capabilities of individuals.
An interactive computer simulation of an inverted pendulum which takes input from
artificial and human controllers was programmed in Matlab to determine the effec
tiveness of cooperative shared control. A proportional-derivative (PD) controller was
used as the artificial/computer side of the shared control. Input from a human op
erator was obtained using an Xbox 360 controller, with biofeedback provided by a
at panel display. The artificial controller and human worked together to balance the
inverted pendulum vertically and prevent it from falling below the horizontal axis.
Random perturbations were provided to destabilize the system. The amount of time
in which a participant could maintain stability was used as a performance measure
ment.
In competitive shared control the computer assists the human in completing the pri
mary task. However, in addition, the human works to achieve a secondary task while working symbiotically with the artificial controller. This may result in conditions
where the human is competing with the artificial controller to achieve di erent goals.
Note that this type of shared control is different than the winner takes all competitive
control because in
uence from each source is always present. The amount of time the
pendulum is balanced and how long the pendulum remained within the target area
was used as a performance measurement.
A total of 20 participants for the cooperative shared control and 12 participants for
the competitive shared control were evaluated at 26 different testing conditions in
a pseudo-randomized order. Each test condition was repeated three times for each
participant and the result for each test condition was averaged. The results from both
the cooperative and competitive shared control testing were very promising. The
results showed that blended shared control can outperform a human and that higher
performance can be achieved by increasing the PD level. Blended shared control
can also perform better than an artificial PD controller alone when the diffculty
increases beyond the controller's capabilities. This same observation can be made
when comparing blended shared control to additive performance. Competitive testing
was also able to show that giving the human a secondary task to complete did not
interfere with primary task completion. By lightening the load of a primary task,
blended shared control could enable someone to perform additional tasks or allow
them to perform them better than they could on their own.
Effectiveness of cooperative and competitive shared control
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Created on 4/1/2014
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Additional Information
- Publication
- Thesis
- Language: English
- Date: 2014
- Keywords
- Shared Control
- Subjects
- Human-machine systems -- Evaluation
- Human-machine systems -- Manual control -- Evaluation