Motorized scroll wheel for an input device
A peripheral device may include a body. The device may include a scroll wheel rotatably coupled with the body. The scroll wheel may include a ferromagnetic rotor. The rotor may be generally annular and may define an open interior. The rotor may define a first plurality of teeth arranged about a periphery of the open interior. The device may include a stator disposed within the open interior. The stator may define a second plurality of teeth that are alignable with the first plurality of teeth. The stator may include a plurality of electro-permanent magnets. Each of the electro-permanent magnets may be disposed within a conductive coil. The device may include a position sensor that is configured to detect an angular position of the rotor. The device may include control circuitry that controls delivery of current to the electro-permanent magnets of the stator to controls a speed of the scroll wheel.
1. A system comprising:
a peripheral device comprising:
a body;
a wheel rotatably coupled to the body, the wheel at least partially exposed outside of the body such that a user may interact with the rotating wheel via a user's finger;
a motor comprising at least:
a first portion of the motor coupled to the wheel; and
a second portion of the motor coupled to the body,
wherein the first and second portions of the motor are configured to interact with each other to provide an acceleration force to the wheel;
a sensor configured to detect the rotational speed of the wheel;
a processor configured to:
receive an input from the sensor related to the rotational speed of the wheel; and
drive the motor to maintain rotation of the wheel at a speed imparted to the wheel by the user's finger;
a host machine; and
an application running on the host machine configured to receive an input from the peripheral device,
wherein an event on the host machine, related to the input received from the peripheral device, causes data to be sent to the processor of the peripheral device, and
wherein in response to receiving the data, the processor configured to drive the motor to decelerate the speed of the wheel.
2. The system of claim 1 wherein the first portion is a rotor coupled to the wheel.
3. The system of claim 2 wherein the second portion is a stator coupled to the body.
4. The system of claim 1 wherein the sensor is a position sensor and has a sampling rate of at least 10 kHz.
5. The system of claim 1 wherein the peripheral device is a computer mouse and the wheel is a scroll wheel.
6. The system of claim 1 wherein the peripheral device is a keyboard device and the wheel is a scroll wheel.
7. The system of claim 1 wherein the first portion is a ferromagnetic rotor, and wherein:
the ferromagnetic rotor is generally annular and defines an open interior; and
the ferromagnetic rotor defines a first plurality of teeth arranged about a periphery of the open interior,
wherein the second portion is a stator disposed within the open interior of the ferromagnetic rotor, the stator defining a second plurality of teeth that are at least substantially alignable with the first plurality of teeth, wherein the stator comprises at least one permanent magnet and a plurality of electro-permanent magnets, wherein each of the plurality of electro-permanent magnets is disposed within a conductive coil.
8. The system of claim 7 wherein each of the plurality of electro-permanent magnets is coupled with a respective permanent magnet that is disposed within the respective conductive coil.
9. The system of claim 8 wherein the plurality of electro-permanent magnets comprise three electro-permanent magnets arranged in a triangular configuration.
10. The system of claim 1 wherein the host machine is a host computing device.
11. The system of claim 1 wherein the driving the motor includes increasing the speed of the wheel as the wheel slows down due to friction in order to maintain rotation of the wheel at a speed imparted to the wheel by the user's finger.
12. The system of claim 1 wherein the sensor detects an angular position of the wheel.
13. The system of claim 1 wherein the sensor is a Hall Effect sensor.
14. The system of claim 1 wherein the motor is a brushless motor.
15. The system of claim 1 wherein the motor is a pancake motor.
16. The system of claim 1 wherein a maximum speed of the wheel via the motor is at least 2400 rpm.
17. The system of claim 1 wherein a maximum available torque of the wheel via the motor is at least 10 mNm.
18. The system of claim 1 wherein a minimum stall torque is 20 mNm.