Force sensitive input devices and methods

1. An input device comprising:

a first input key configured to output a first analog signal as a function of force applied to the first input key;

a second input key configured to output a second analog signal as a function of force applied to the second input key;

a third input key configured to output a third analog signal as a function of force applied to the third input key;

a fourth input key configured to output a fourth analog signal as a function of force applied to the fourth input key; and

a controller configured to calculate a first vector having a first magnitude based on a value of the first analog signal, calculate a second vector having a second magnitude based on a value of the second analog signal, calculate a third vector having a third magnitude based on a value of the third analog signal, calculate a fourth vector having a fourth magnitude based on a value of the fourth analog signal, and output movement data including both direction and magnitude that represent a vector addition of the first, second, third, and fourth vectors, the movement data being formatted for presentation to a driver of a computing device.

2. The input device of claim 1 , wherein the controller is configured to format the movement data according to either the DirectInput protocol or the XInput protocol.

3. The input device of claim 1 , wherein the controller is configured to format the movement data to a scale expected by the driver of the computing device.

4. The input device of claim 3 , wherein the controller is configured to format the movement data to the scale expected by the driver of the computing device based on a user-adjustable mapping.

5. The input device of claim 1 , wherein the movement data includes an x-axis component and a y-axis component, the x-axis component being a function of the first and second analog signals, and the y-axis component being a function of the third and fourth analog signals.

6. The input device of claim 5 , wherein:

the x-axis component represents a first distance from a resting point, the first distance being proportional to a force applied to one of the first and second input keys; and

the y-axis component represents a second distance from the resting point, the second distance being proportional to a force applied to one of the third and fourth input keys.

7. The input device of claim 1 , wherein the controller comprises an analog-to-digital converter (ADC) configured to convert the first, second, third, and fourth analog signals into digital signals.

8. The input device of claim 7 , further comprising a low-pass filter configured to reduce noise in at least one of the first, second, third, and fourth analog signals before the analog signal is received by the ADC of the controller.

9. The input device of claim 1 , further comprising a number of binary input keys, each of the binary input keys being configured to output a digital signal indicating whether or not the binary input key has been pressed.

10. The input device of claim 1 , wherein the first, second, third, and fourth input keys each comprise:

a button movable along a respective axis between a first end position and a second end position;

a resilient component biasing the button toward the first end position; and

a sensor configured to measure a displacement of the button along the respective axis away from the first end position and toward the second end position and to output the respective analog signal in response to the measured displacement of the button.

11. The input device of claim 10 , wherein the button of each of the first, second, third, and fourth input keys comprises:

a keycap configured to be pressed by a user to move the button along the respective axis away from the first end position and toward the second end position; and

a plunger supporting the keycap, the plunger engaging the resilient component.

12. The input device of claim 10 , wherein the resilient component of each of the first, second, third, and fourth input keys is configured to allow a displacement of the button along the respective axis away from the first end position and toward the second end position that is proportional to a force applied to the button by a user.