Patent Application
20080042975
The following description is presented to enable embodiments of the invention to be made and used, and is provided in the context of a patent application and its requirements. Various modifications to the disclosed embodiments will be readily apparent, and the generic principles herein may be applied to other embodiments. Thus, the invention is not intended to be limited to the embodiments shown but is to be accorded the widest scope consistent with the appended claims. Like reference numerals designate corresponding parts throughout the figures.
If the user is not using the pointing device in a new location, the method passes to block 204 where the user observes the object in a visual scene and moves the pointing device to move or control the object. For example, the visual scene is an image displayed on a display and the user moves the pointing device to control the movement of a cursor included in the image in an embodiment in accordance with the invention. Examples of display devices include, but are not limited to, a computer, digital video recorder, television, music player, and personal digital assistant.
In another embodiment in accordance with the invention, the visual scene includes a view of the object and the user moves the user-controlled pointing device to control the movement of a remote-controlled object. Examples of such objects include, but are not limited to, a remote-controlled electronic device, such as a remote controlled toy, a gaming system, or an industrial robot used in a manufacturing or testing facility.
Next, at block 206, each magnetic sensor in the pointing device measures the magnetic field component associated with a respective orthogonal direction. The measured magnetic field components are then filtered to isolate the DC magnetic field components, as shown in block 208. The DC magnetic field components are used for navigation in one embodiment in accordance with the invention because the speed of the changes in the DC magnetic field components is comparable to the speed at which a user moves his or her hand or hands.
A determination is then made at block 210 as to whether a gain is to be applied to one or more DC magnetic field components. A gain or scaling factor translates the movement of the pointing device to a field of motion associated with the object in an embodiment in accordance with the invention. If a gain is to be applied, the method passes to block 212 where the gain values are received and applied to the one or more DC magnetic field components. Each gain value is individually adjustable and programmed by a user in an embodiment in accordance with the invention. In another embodiment in accordance with the invention, the gain values are set by a manufacturer and stored in memory.
Next, at block 214, the changes in the position of the pointing device are tracked and translated into corresponding changes in object positions, movements, or functions. The positional information associated with the object is then transmitted to a controller associated with the object. For example, the positional information is transmitted to a display controller when the user is controlling the movement of a cursor on a display device. A determination is then made at block 216 as to whether the user is continuing to move the pointing device. If so, the method returns to block 206 and repeats each time the user moves the user-controlled pointing device.
Referring now to
The magnetic field component associated with the orthogonal direction is measured while the pointing device is moving and the differences in the magnetic field component determined in order to calculate the distance the pointing device moved in the one orthogonal direction (block 302). A determination is then made at block 304 as to whether there is another orthogonal direction in the field of motion that needs to be calibrated. If so, the method returns to block 300 and repeats until all of the magnetic field components and distances have been determined.
The distances in the field of motion for the pointing device are then translated into distances in a field of motion for the object, as shown in block 306. This typically involves applying a scaling factor or gain to one or more magnetic field components so that the object moves with a desired speed and accuracy within its field of motion. Other embodiments in accordance with the invention can translate the distances in the field of motion for the pointing device into distances in a field of motion for the object using different techniques.
Surface 410 is a flat surface that allows pointing device 400 to move in two orthogonal directions (e.g., x-direction and y-direction) in the embodiment shown in
As discussed earlier, the pointing device uses local pervasive magnetic fields to determine positional information. Thus, magnetic sensors 402, 404 are sufficiently sensitive to measure at least a portion of the terrestrial fields, depending on how and where pointing device 400 is used. Magnetic sensors 402,404 are implemented as one of several commercially available magnetic sensors in an embodiment in accordance with the invention. Examples of such sensors include, but are not limited to, a complementary-metal-oxide-semiconductor (CMOS) fluxgate magnetometer designed by AICHI Micro Intelligent Corporation, or a digital magnetic compass component designed by Honeywell International.
As pointing device 400 moves over surface 410, each magnetic sensor 402, 404 generates an output signal that represents the respective magnetic field component measured by that sensor. Processing circuit 406 receives the output signals and tracks the direction and speed associated with the movement of the pointing device by analyzing the output signals from sensors 402, 404. The changes in the magnetic field components between measurement points are used to determine both the distance and the speed traveled by the pointing device.
Once the movement of pointing device 400 is determined, processing circuit 406 translates the motion of pointing device 400 into corresponding positional information for cursor 412 displayed on display device 414. Communications device 408 transmits corresponding positional information to controller 416 associated with display device 414 using a communications device associated with display device 414 (not shown) and communications link 418. Cursor 412 is moved on display 414 in response to the positional information. Based on the actions taken by a user and the changes in the image displayed on display 414, the user can repeatedly re-position cursor 412 by moving pointing device 400.
Although processing circuit 406 is described as receiving output signals from magnetic sensors 402, 404 and determining both the movement of pointing device 400 and the corresponding positional information for cursor 412, other embodiments in accordance with the invention are not limited to this implementation. By way of example only, processing circuit 406 receives the output signals from magnetic sensors 402, 404 but controller 416 determines both the movement of pointing device 400 and the corresponding positional information for cursor 412 in another embodiment in accordance with the invention. In another example, processing circuit 406 receives the output signals from magnetic sensors 402, 404 and determines the movement of pointing device 400 and controller 416 determines the corresponding positional information for cursor 412 in another embodiment in accordance with the invention.
Display device 414 is implemented separately from pointing device 400 in an embodiment in accordance with the invention. In another embodiment in accordance with the invention, display device 414 and pointing device 400 are assembled within the same host device.
Communications link 416 is implemented as a wired communications link or a wireless communications link. Output device 408 is implemented as any known output device that can transmit and receive data over a wired or wireless connection. By way of example, only, output device 408 is implemented as a Bluetooth-enabled wireless component in an embodiment in accordance with the invention.
And finally, pointing device 400 can be implemented with a different number of magnetic sensors in other embodiments in accordance with the invention. For example, surface 410 can be designed to constrain the movement of pointing device 400 to only one direction (e.g. side-to-side or up/down). In this situation, pointing device is constructed with only one magnetic sensor.
In another embodiment in accordance with the invention, surface 410 is flat but a user can rotate pointing device over surface 410. Pointing device 400 therefore includes three magnetic sensors to measure the local gradient of the volume of the magnetic field in the plane of surface 410. When the x and y magnetic field components of the gradient in the plane of surface 410 have been extracted, then translation of pointing device 400 on surface 410 can be mapped to the horizontal and vertical cursor motion on the display screen.
As discussed earlier, embodiments in accordance with the invention are not limited to using a pointing device that measures magnetic fields to control the movement of a cursor on a display screen. A pointing device that measures magnetic fields can be used to control the movement or function of any number of objects that can be controlled remotely. Examples of such objects include, but are not limited to, vehicles, testing devices, manufacturing equipment, toys, industrial robots, and consumer products such as music players, digital video recorders, and appliances. A user-controlled pointing device can be used to move an object or select a function associated with an object in various embodiments in accordance with the invention.
Referring now to
Pointing device 500 includes magnetic sensors 502, 504, 506, processing circuit 508, and communications device 408. Pointing device 500 is moved in free space or over a three dimensional surface in the embodiment shown in
Magnetic sensors 502, 504, 506 are positioned within pointing device 500 such that sensors 502, 504, 506 are orthogonal to each other. With three dimensional movements, sensor 502 measures the magnetic field component in the x-direction, sensor 504 measures the magnetic field component in the y-direction, and sensor 506 measures the magnetic field component in the z-direction. Magnetic sensors 502, 504, 506 are implemented as one of several commercially available magnetic sensors, such as, for example, a digital magnetic compass component designed by Honeywell International.
As pointing device 500 moves, each magnetic sensor 502, 404, 506 generates one or more output signals that represent the respective magnetic field component measured by that sensor. Processing circuit 508 receives the output signals and applies a gain to one, two, or all three signals, if necessary. The direction, speed, and angular rotation associated with the moving of pointing device 500 are then determined by analyzing the output signals from sensors 502, 504, 506. The changes in the magnetic field components between measurement points are used to determine the distance, speed, and angular rotation traveled by pointing device 500. Corresponding positional information for robot 514 is then transmitted to controller 516 associated with robot 514 using communications link 418.
Although processing circuit 508 is described as receiving output signals from magnetic sensors 502, 504, 506 and determining both the movement of pointing device 500 and the corresponding positional information for robot 514, other embodiments in accordance with the invention are not limited to this implementation. By way of example only, processing circuit 508 receives the output signals from magnetic sensors 502, 504, 506 and determines the movement of pointing device 500 and controller 516 determines the corresponding positional information for robot 514 in another embodiment in accordance with the invention.
Referring now to
Embodiments in accordance with the invention are not limited to the mounting scheme shown in
The magnetic fields measured by pointing device 400 and pointing device 500 are derived generally from the earth's geo-magnetic fields in an embodiment in accordance with the invention. This allows the pointing device to operate on any surface, including clean, clear glass. The tracking information can also be obtained with a pointing device that moves through free space, such as a game controller or remote controller that provides positional information to any type of an object.
