A joystick composed of a stator formed by an outer cage forming an inner cubic compartment containing an inner cube oriented with its wall spaced from and substantially parallel corresponding wall of the compartment. Opposed magnets are position in cooperating relationship on opposed walls of the compartment...http://www.google.com.tw/patents/US6195083?utm_source=gb-gplus-share專利 US6195083 - Active joystick with optical positions sensor
