These involve changes to the lithium chemistry of batteries, their mechanical properties and the electronics that control them.

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Thus Paul Sharits's stroboscopic flicker film "Epileptic Seizure Comparison" (1976) appears near images of what in psychiatry have been dubbed "influencing machines, " mechanical objects that some schizophrenics imagine control their thoughts and actions.

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"This is a fundamentally new technology that allows us to control electronic devices directly using mechanical agitation, " Prof Wang added.

BBC: Sensors

He therefore wondered if he could use EEG-based control to operate a set of mechanical legs.

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Mechanical linkages connect the joysticks and rudder pedals to external surfaces that control pitch, roll and heading.

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This approach can provide incredible control over an artificial arm, but patients often prefer to use simpler, mechanical prosthetics.

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It is easy for parking software to control because it involves switching electric motors on and off, rather than operating mechanical pumps.

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The fine-grained control that the command software enables combined with a design that is more electrical than mechanical creates enormous flexibility in how the different systems can be coordinated.

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"Any mechanical motion, such as the movement of arms or the fingers of a robot, could be translated to control signals, " said Zhong Lin Wang, a professor at the Georgia Institute of Technology.

BBC: Sensors

Aside from mechanical challenges, what was missing that may have spurred personal robotics development was a dedicated programming language specifically for robot control and communication.

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