An intelligent material unit formed of an intelligent gel encapsulated within an enclosure. When the gel is actuated by a change in temperature thereof, such as heat and/or by an externally applied field such as an electrical current, electric field, magnetic field, ultrasonic energy (or sonic), microwave...http://www.google.fr/patents/US5951600?utm_source=gb-gplus-shareBrevet US5951600 - Medical devices using electrosensitive gels