Abstract: Techniques are provided for measuring angles of rotation of a rotatable body, and, in particular, for measuring angles of rotation of a rotating member that can rotate greater than 360 degrees. One example of these techniques is multi-turn angular position sensor that includes a main gear configured to couple to and rotate, in response to rotation of a rotation member, over a main gear rotation range, a first sensor gear engaged with the main gear and configured to experience more angular rotation than the main gear in response to rotation of the main gear, and a second sensor gear engaged with the main gear and configured to experience more angular rotation than the main gear and less angular rotation than the first sensor gear in response to rotation of the main gear.

Abstract: A multi-turn angular position sensor a main gear configured to couple to and rotate, in response to rotation of a rotation member, over a main gear rotation range, a first sensor gear engaged with the main gear and configured to experience more angular rotation than the main gear in response to rotation of the main gear, and a second sensor gear engaged with the main gear and configured to experience more angular rotation than the main gear and less angular rotation than the first sensor gear in response to rotation of the main gear. The angular position sensor also includes a first angular position sensor configured to sense rotation of the first sensor gear and to generate a first output signal indicative of rotation of the first sensor gear, and a second angular position sensor configured to sense rotation of the second sensor gear and to generate a second output signal indicative of rotation of the second sensor gear.