Magnetic controller for device control

1. A method to control a computer peripheral device, comprising:

determining, by a magnetometer of the device, a magnetic field measurement specifying a strength and a direction of a surrounding magnetic field that surrounds the magnetometer;

determining whether the device is to be controlled by a particular magnetic controller of a plurality of different magnetic controllers based on the magnetic field measurement indicating a respective reference magnetic field measurement that is present when the device is placed within a magnetic field of the particular magnetic controller, wherein:

each different magnetic controller includes a plurality of respective magnetic input actuators that are each operatively coupled to a respective magnetic device and that when manually actuated by a user causes a respective magnetic controller to alter the surrounding magnetic field according to a predefined change associated with the plurality of respective magnetic input actuators;

each different magnetic controller is a different type of magnetic controller of a plurality of types of magnetic controllers; and

each respective type of magnetic controller has a different respective reference magnetic field measurement and a different respective input model of a plurality of input models;

in response determining that the device is not to be controlled by the particular magnetic controller external to the device, not interpreting changes to magnetic fields as commands; and

in response determining that the device is to be controlled by the particular magnetic controller external to the device:

selecting a respective input model for the particular magnetic controller from the plurality of input models based on a respective type of the particular magnetic controller which is determined from the respective reference magnetic field measurement, wherein the respective input model maps magnetic field changes caused by user actuation of the plurality of magnetic input actuators to a plurality of user inputs supported by the particular magnetic controller, wherein each respective input model describes different actions for each respective magnetic controller;

determining, by the magnetometer of the device, a series of subsequent magnetic field measurements, each subsequent magnetic field measurement specifying a strength and a direction of a surrounding magnetic field that surrounds the magnetometer and generated by actuation of the particular magnetic controller to which the reference magnetic field measurement corresponds;

for each subsequent magnetic field measurement:

determining, by a processor of the device, a difference between the respective reference magnetic field measurement that is present when the device is placed within the magnetic field of the respective magnetic controller and the subsequent magnetic field measurement;

determining, by the processor of the device, whether the difference between the respective reference magnetic measurement and the subsequent magnetic field measurement meets a threshold change according to the respective input model; and

for each difference that does meet the threshold change, determining, based on the respective input model, a user input to the device based on the respective input model.

2. The method of claim 1 , further comprising:

for each difference that does not meet the threshold change, not interpreting the difference as a user input to the device.

3. The method of claim 1 , wherein:

the magnetic field measurements specify a three-dimensional magnetic field vector and a magnitude of the three-dimensional magnetic field vector; and

the respective input model maps changes in the three-dimensional magnetic field vector and changes in the magnitude of the three-dimensional magnetic field vector to a plurality of inputs.

4. The method of claim 3 , wherein the respective input model maps the changes in the three-dimensional magnetic field vector and changes in the magnitude of the three-dimensional magnetic field vector to a plurality of inputs by mapping each of the plurality of inputs to discrete changes in a direction of the three-dimensional magnetic field vector and discrete changes in the magnitude of the three-dimensional magnetic field vector to a plurality of input.

5. The method of claim 1 , further comprising:

determining an orientation of the device relative to the particular magnetic controller that is external to the device; and

wherein determining, based on the respective input model, a user input to the device based on the respective input model comprises determining the user input to the device only if the orientation of the device relative to the respective reference magnetic field meets an orientation criterion that defines an orientation of the device relative to the respective magnetic controller.

6. A computer peripheral device, comprising:

a data processing apparatus including a processing subsystem and a magnetometer, the data processing apparatus operable to:

determine, by the magnetometer of the device, a magnetic field measurement, the magnetic field measurement specifying a strength and a direction of a surrounding magnetic field that surrounds the magnetometer;

determine whether the device is to be controlled by a particular magnetic controller of a plurality of different magnetic controllers based on the magnetic field measurement indicating a respective reference magnetic field measurement that is present when the device is placed within a magnetic field of the particular magnetic controller, wherein:

each different magnetic controller includes a plurality of respective magnetic input actuators that are each operatively coupled to a respective magnetic device and that when manually actuated by a user causes a respective magnetic controller to alter the surrounding magnetic field according to a predefined change associated with the plurality of respective magnetic input actuators;

each different magnetic controller is a different type of magnetic controller of a plurality of types of magnetic controllers; and

each respective type of magnetic controller has a different respective reference magnetic field measurement and a different respective input model of a plurality of input models;

in response determining that the device is not to be controlled by the particular magnetic controller external to the device, not interpreting changes to magnetic fields as commands; and

in response determining that the device is to be controlled by the particular magnetic controller external to the device:

select a respective input model for the particular magnetic controller from the plurality of input models based on a respective type of the particular magnetic controller which is determined from the respective reference magnetic field measurement, wherein the respective input model maps magnetic field changes caused by user actuation of the plurality of magnetic input actuators to a plurality of user inputs supported by the particular magnetic controller, wherein each respective input model describes different actions for each respective magnetic controller;

determine, by the magnetometer of the device, a series of subsequent magnetic field measurements, each subsequent magnetic field measurement specifying a strength and a direction of the surrounding magnetic field that surrounds the magnetometer and generated by actuation of the particular magnetic controller to which the reference magnetic field measurement corresponds;

for each subsequent magnetic field measurement:

determine, by a processor of the device, a difference between the respective reference magnetic field measurement that is present when the device is placed within the magnetic field of the respective magnetic controller and the subsequent magnetic field measurement;

determine, by the processor of the device, whether the difference between the respective reference magnetic measurement and the subsequent magnetic field measurement meets a threshold change according to the respective input model; and

for each difference that does meet the threshold change, determine, based on the respective input model, a user input to the device based on the respective input model; and

a magnetic controller of the plurality of different magnetic controllers external to the data processing apparatus, the magnetic controller including:

a magnetic device for altering the surrounding magnetic field; and

one or more magnetic input actuators, each operatively coupled to the magnetic device and that when actuated cause the magnetic device alter the surrounding magnetic field according to a predefined change associated with the magnetic input actuator.