Patent ID: 7953319

Claim:
A position controller adapted to be used with a shape-memory-alloy actuator adapted to move a movable member using a shape-memory-alloy member in a biased manner, and to be used with a first stopper member configured to restrict a movable range of the movable member, said position controller comprising: a control section operable to control a position of said movable member, by using, as a reference value, a first resistance value corresponding to a first change point at which a resistance change rate per unit temperature change in said shape-memory-alloy member changes from a first rate to a second rate different from said first rate; a driving section operable to supply electric power to said shape-memory-alloy member so as to electrically heat said shape-memory-alloy member; a resistance detection section operable to detect a resistance of said shape-memory-alloy member at different electric power levels supplied by the driving section; and a change-point detection section operable to detect said first change point corresponding to the point at which the movable member comes in contact with the first stopper member, said first change point being based on at least two resistances detected by said resistance detection section, with said at least two resistances corresponding to at least two different electric power levels.