Pulse-modulated control, non-linear friction, micron-scale valves, actuators
Control fine movement of micron-scale objects; achieve better 'feel' by eliminating the effect of friction in medical robots interacting with humans or animals; control the position of robotic manipulators or vehicles; modulate the opening and closing of pressure valves in large-scale pipelines in the energy industry.
Various feedback control systems cannot work if the friction is highly non-linear or non-repeatable.
This invention uses a feedback control strategy - Pulse-Modulated (PM) control - to address friction-induced non-linearities. The PM control strategy effectively overcomes the hard non-linearities in a system which cannot be remedied by other conventional feedback control strategies. This research shows that this method works well on a system with highly variable non-linearity, and is likely to find successful application to many other systems with similarly challenging non-linearities.
Simple and can overcome highly non-linear, non-repeatable forms of friction.
US Patent Application 12/857827 filed on August 17, 2010
Last revised: Aug 24, 2011