Abstract: A golfing aid system at least partially configured to be mounted on a golfer is provided. The system includes an optical system, an output configured to provide audio and/or visual information, a human wearable support, a first compass mounted on the wearable support, an optical system. The golfing aid system is configured to, when the wearable support is worn by the golfer, obtain a first compass heading from the first compass for a target location observable through the optical system, obtain a second compass heading when the golfer is in a golfing stance, determine, based on at least the first and second compass headings, whether a part of the body that supports the human wearable support is substantially in alignment with a direction, and provide feedback through the output, the feedback being configured to indicate whether or not the golfer is substantially aligned with the direction.

Abstract: A tennis racquet or other athletic instrument configured for striking a moveable ball or other playing element includes electronic sensors for providing an audible or audio-visual indication of the location on the racquet or instrument at which contact is made with the ball or other playing element. Various devices for sensing the location of contact are disclosed.

Abstract: A tennis racquet or other athletic instrument configured for striking a moveable ball or other playing element includes electronic sensors for providing an audible or audio-visual indication of the location on the racquet or instrument at which contact is made with the ball or other playing element. Various devices for sensing the location of contact are disclosed.