CONTROLLER WITH TACTILE SENSORS

Abstract: A controller with a plurality of tactile sensors (200) may be used for one, two or three parameter control in applications requiring manual user control of parameters such as temperature, volume, speed, direction and cursor position on a computer screen. The controller comprises two or more tactile force sensors (100) and a computing device (800). The centers of the tactile sensors are positioned at angles about a common center point. The computing means determines a magnitude and a direction of a resultant force from all the tactile sensors, using the force applied to each tactile sensor and the angle at which the center of each tactile sensor is oriented about a common center point. The configuration enables sensing applied force in two or more directions at angles from a common center point. Another parameter may be controlled based on the total force applied to all of the tactile sensors of the controller.

Description: CONTROLLER WITH TACTILE SENSORS This invention relates generally to devices for receiving manual user input for control of parameters such temperature, volume, speed, direction, and cursor movement on a computer screen. It relates to the field of computer input devices where joy sticks, mice, and track balls find common usage as pointing devices. The present invention is a tactile device based on analog control and has an output resistance which varies with the force applied to the device. It relates more specifically to an improved device for electronic positional and directional control using a plurality of individual tactile sensors. Various electronic positional and directional control devices are available that enable a user to control either one or two parameters. An example of one parameter control is the use of up arrow keys and down arrow keys to scroll text in an up or down direction on a computer screen when using a word processor computer program. Touch pads are also used for one parameter control in applications requiring manual control, such as the liquid level in a container or volume from an acoustic speaker system. It is desirable that a controller device with tactile sensors be relatively simple and reliable, that the controller device does not require finger repositioning or frequent cleaning and maintenance, that the controller device have no moving parts and no requirement for mechanical preloading, and that the controller device be capable of providing for one, two, or three parameter control. BRIEF DESCRIPTION OF THE DRAWINGS These and other features, aspects, and advantages of the present invention will become better understood with regard to the following description, appended claims, and accompanying drawings where: Fig. 1 is an exploded view of a two device controller with tactile sensors having a flexible circular pad over the two tactile sensing devices; Fig. 2 is an exploded view of a four device controller with tactile sensors having a flexible semi-spherical pad over the four tactile sensing devices; Fig. 3 shows two partially overlapping tactile sensing devices of a two device controller with tactile sensors; Fig. 4 shows three partially overlapping tactile sensing devices of a three device controller with tactile sensors; Fig. 5 shows four partially overlapping tactile sensing devices of a four device controller with tactile sensors; and Fig. 6 shows two interdigitated tactile sensing devices of a two device controller with tactile sensors. DETAILED DESCRIPTION OF THE INVENTION Referring now to Fig. 1, a two device controller with tactile sensors 200 is shown in accordance with the present inventive concepts. The two device controller with tactile sensors 200 comprises two force sensors 100, each force sensor 100 having a circular tactile sensing device 150 electrically connected to a resultant force computing means 800. The resultant force computing means 800 may compute a first control parameter comprising a normalized resultant force magnitude and polarity in the +X direction 710 or -X direction 720, as well as a total force that provides a second control parameter. A flexible circular pad 910 is provided to distribute applied tactile forces to the tactile sensing devices 150. The two tactile sensing devices 150 partially overlap one another, as shown in Fig.3. The force sensors 100 may use any one of several different sensing technologies that are well known in the art, including but not limited to piezoelectric devices, capacitive devices, semiconductor devices and conductive ink devices. The preferred embodiment of the force sensors 100 uses a force sensitive ink and is described in United States Letters Patent 5,541,570 issued on July 30, 1996, Force Sensing Ink, Method of Making Same and Improved Force Sensor by Donald J. McDowell. For brevity, the disclosure contained in this reference will not be repeated here. The size of each the circular tactile sensing devices 150 is typically approximately one centimeter in diameter. For example, the tactile force sensors may be formed by positioning a thin layer of force sensitive resistive material, such as a force sensing ink, between two thin backing sheets and by providing a means for measuring the change in resistance of the resistive material due to an applied force on the sensing means . Turning now to Fig. 2, a four device controller with tactile sensors 400 is shown in accordance with the present inventive concepts . The four device controller with tactile sensors 400 comprises four force sensors 100, each force sensor 100 having a circular tactile sensing device 150 electrically connected to a resultant force computing means 800. The resultant force computing means 800 may compute a first control parameter comprising a first normalized resultant force magnitude and polarity in the +X direction 710 or -X direction 720, a second control parameter comprising a second normalized resultant force magnitude and polarity in the +Y direction 730 or the -Y direction 740, as well as a total force that provides a third control parameter. The resultant force computing means 800 may also compute a third normalized force magnitude and direction in a plane of the X and Y axis using the first and second normalized resultant force magnitudes and directions. A flexible semi-spherical pad 920 is provided to distribute applied tactile forces to the tactile sensing devices 150. The four tactile sensing devices 150 partially overlap one another, as shown in Fig. 5. Fig. 3 depicts a typical configuration of a tactile area 930 of a controller with tactile sensors 210 that has two partially overlapping circular tactile sensing devices 150. The diameter of each of the tactile sensing devices 150 is approximately one centimeter. The tactile sensing devices 150 are circumscribed within a tactile area 930 of approximately one and one-half centimeters diameter. The center of each tactile sensing device 150 is positioned at equal angles about the center of the circular tactile sensing area. Fig. 4 depicts another typical configuration of a tactile area 930 of a controller with tactile sensors 310 that has three partially overlapping circular tactile sensing devices 150. The diameter of each of the tactile sensing devices 150 is approximately one centimeter. The tactile sensing devices 150 are circumscribed within a tactile area 930 of approximately one and one-half centimeters diameter. The center of each tactile sensing device 150 is positioned at equal angles about the center of the circular tactile sensing area. Fig. 5 depicts yet another typical configuration of a tactile area 930 of a controller with tactile sensors 410 that has four partially overlapping circular tactile sensing devices 150. The diameter of each of the tactile sensing devices 150 is approximately one centimeter. The tactile sensing devices 150 are circumscribed within a tactile area 930 of approximately one and one-half centimeters diameter. The center of each tactile sensing device 150 is positioned at equal angles about the center of the circular tactile sensing area. Fig. 6 shows a typical configuration of a tactile area 930 of a controller with tactile sensors 220 that has a pair of circular interdigitated tactile sensing devices 160. The diameter of each of the interdigitated tactile sensing devices 160 is approximately one centimeter. The tactile sensing devices 160 are circumscribed within a tactile area 930 of approximately one and one-half centimeters diameter. The center of each tactile sensing device 160 is positioned at equal angles about the center of the circular tactile sensing area. There are a multitude of geometric variations that may be applied to the present inventive concept that does not exceed the scope of the present disclosure. For example, the shape of the tactile sensing devices is not limited to a circle, but may be an ellipse, a triangle, a square, a rectangle, or any polygon such as a hexagon or an octagon. The number of tactile sensing devices is also not limited to the two, three, or four that have been described. Other than requiring two or more devices, the number may be increased almost indefinitely, thus providing a greater resolution to the angular directional component. Another possible variation is operation of the controller with tactile sensors directly from a finger rather than interposing a pad for force distribution to the tactile sensing devices. The sensitivity of the controllers may also be tuned by adjusting the distance of the centers of the tactile sensing devices from the center of the circular tactile area. The sensitivity to applied forces in angular directions along the lines connecting the center of each tactile sensing device and the center of the circular tactile sensing area is increased by moving the center of each tactile sensing device closer to the center of the circular sensing area. The sensitivity to applied forces in angular directions between the lines connecting the center of each tactile sensing device and the center of the circular tactile sensing area is increased by moving the center of each tactile sensing device farther away from the center of the circular sensing area.

Claims: CLAIMS : 1. A controller with tactile sensors (200) comprising : (a) two or more tactile force sensors (100), each having a center, angularly positioned about a common center point for sensing an applied force in two or more angular directions from the common center point; and (b) computing means (800) for computing a resultant force magnitude and a resultant force direction based on the applied force on each tactile force sensor and the angular direction about the common center point to the center of each tactile sensing means. 2. A controller with tactile sensors (200) according to Claim 1 wherein the two or more tactile force sensors (100) are partially overlapping each other. 3. A controller with tactile sensors (200) according to Claim 1 wherein the shape of the tactile force sensors (100) is selected from the group consisting of circles, ellipses, triangles, squares, rectangles, hexagons and octagons. 4. A controller with tactile sensors (200) according to Claim 1 wherein the tactile force sensors (100) are shaped in an interdigitated manner with each opposing tactile sensing means. 5. A controller with tactile sensors (200) according to Claim 1 wherein the tactile force sensors (100) are formed by positioning a thin layer of force sensitive resistive material between two thin backing sheets and by providing a means for measuring the change in resistance of the resistive material due to an applied force on the sensing means. 6. A controller with tactile sensors (200) according to Claim 5 wherein the pressure sensitive resistive material is a force sensing ink. 7. A controller with tactile sensors (200) according to Claim 1 further comprising a flexible semi-spherical pad positioned over the tactile force sensors (100) for distributing an applied force to the two or more tactile sensing means. 8. A controller with tactile sensors (200) according to Claim 1 further comprising a flexible circular pad positioned over the tactile force sensors (100) for distributing an applied force to the two or more tactile force sensors . 9. A controller with tactile sensors (200) according to Claim 1 wherein the computing means (800) further comprises a means for computing the sum of the magnitudes of the applied force to each tactile force sensor (100) thereby providing a total force control parameter in addition to the resultant force magnitude and the resultant force direction. 10. A controller with tactile sensors (200) according to Claim 1 wherein the sensitivity to forces in angular directions along lines connecting the center of each tactile sensing means and the common center point is increased by moving the center of each tactile force sensors (100) closer to the common center point.

Inventors: PODOLOFF ROBERT MICHAEL, PODOLOFF, ROBERT, MICHAEL
Applicants: BREED AUTOMOTIVE TECH, BREED AUTOMOTIVE TECHNOLOGY, INC.
Application year: 1998
Main classification: G09G
IPC codes: G06F3