3D pointing devices with orientation compensation and improved usability
View Patent ↗Systems and methods according to the present invention describe 3D pointing devices which enhance usability by transforming sensed motion data from a first frame of reference (e.g., the body of the 3D pointing device) into a second frame of reference (e.g., a user's frame of reference). One exemplary embodiment of the present invention removes effects associated with a tilt orientation in which the 3D pointing device is held by a user.
1. A method for controlling an object by a device comprising the steps of:
detecting movement of the device using an accelerometer and at least one other sensor in the device, the movement being in a body frame of reference;
transforming the detected movement from the body frame of reference to another frame of reference; and
using the transformed movement to generate an output of the device for controlling said object,
wherein the step of transforming is calculated by:
Pu =Rotate( Pb,Q )+ P delta
Pu ′=Rotate( Pb′,Q )
Pu ″=Rotate( Pb″,Q )
Wu =Rotate( Wb,Q )
Wu ′=Rotate( Wb′,Q )
where:
Rotate represents a quaternion rotation operator such that Rotate(A, Q) is equal to Q*A Q where Q* is a quaternion conjugate and a vector A is a quaternion with a complex component equal to A and a real component equal to 0;
Pu is a position in the another frame of reference;
Pb is a position in the body frame of reference;
′ represents a derivative;
Wu is an angular velocity of the device in body angles in the another frame of reference;
Wb is an angular velocity of the device in body angles in the body frame of the device;
Pdelta is a difference between an origin of the another frame of reference and the body frame of reference in the another frame of reference coordinate system; and
Q is the normalized rotation guaternion that represents the rotation from the body frame to the another frame.
2. The method of claim 1 , further comprising the steps of:
interpreting the detected movement to produce an estimate of the detected movement;
converting the detected movement from the body frame of reference to the another frame of reference; and
mapping the transformed movement to produce said output of said device.
3. The method of claim 2 , wherein the step of mapping is performed to output a gesture for controlling said object.
4. The method of claim 3 , wherein said gesture is a command.
5. The method of claim 1 , wherein the step of transforming is performed by a processor external to the device.
6. The method of claim 1 , wherein the step of transforming includes transforming in x, y, and z dimensions and for both translational and rotational motion.
7. The method of claim 1 , wherein the step of transforming includes transforming from x, y, and z dimensions to x and y dimensions.
8. The method of claim 1 , wherein the step of transforming includes transforming only one of translational motion and rotational motion.
9. The method of claim 1 , further comprising the step of:
performing a second transformation to generate the output.
10. A system for controlling an object comprising:
a device, comprising:
an accelerometer; and
at least one other sensor; and a
a processor, external to the device, the processor configured to:
detect movement of the pointing device using the accelerometer and the at least one other sensor in the device, the movement being in a body frame of reference;
transform the detected movement from the body frame of reference to another frame of reference; and
use the transformed movement to generate an output of the device for controlling said object,
wherein the step of transforming is calculated by:
Pu =Rotate( Pb,Q )+Pdelta
Pu ′=Rotate( Pb′,Q )
Pu ″=Rotate( Pb″,Q )
Wu =Rotate( Wb,Q )
Wu ′=Rotate( Wb′,Q )
where:
Rotate represents a quaternion rotation operator such that Rotate(A, Q) is equal to Q*A Q where Q* is a quaternion conjugate and a vector A is a quaternion with a complex component equal to A and a real component equal to 0;
Pu is a position in the another frame of reference;
Pb is a position in the body frame of reference;
′ represents a derivative;
Wu is an angular velocity of the device in body angles in the another frame of reference;
Wb is an angular velocity of the device in body angles in the body frame of the device;
Pdelta is a difference between an origin of the another frame of reference and the body frame of reference in the another frame of reference coordinate system; and
Q is the normalized rotation quaternion that represents the rotation from the body frame to the another frame.
11. The system of claim 10 , wherein the processor is further configured to:
interpret the detected movement to produce an estimate of the detected movement;
convert the detected movement from the body frame of reference to the another frame of reference; and
map the transformed movement to produce said output of said device.
12. The system of claim 11 , wherein the step of mapping is performed to output a gesture for controlling said object.
13. The system of claim 12 , wherein said gesture is a command.
14. The system of claim 10 , wherein the transform step includes transforming in x, y, and z dimensions and for both translational and rotational motion.
15. The system of claim 10 , wherein the transform step includes transforming from x, y, and z dimensions to x and y dimensions.
16. The system of claim 10 , wherein the transform step includes transforming only one of translational motion and rotational motion.
17. The system of claim 10 , wherein the processor is further configured to:
perform a second transformation to generate the output.