SO3 input device

• US 6,670,947 B2
• Filed: 10/22/2001
• Issued: 12/30/2003
• Est. Priority Date: 10/22/2001
• Status: Active Grant

• Current Assignee: Robert William Smyth
• Original Assignee: Robert William Smyth
• Inventors: Smyth, Robert William
• Primary Examiner(s): Mengistu, Amare
• Assistant Examiner(s): SHENG, TOM V
• Application Number:
  US10/007,424
• Publication Number:
  US 20030076304A1
• Time in Patent Office: 799 Days
• Field of Search: 345/156-158, 345/162-167, 341/20-22, 341/31, 341/32
• US Class Current: 345/167
• CPC Class Codes: G06F 3/03549 Trackballs G06F3/03541 takes precedence

Abstract

An apparatus, method and algorithm for the economical, intuitive rotational control of a three dimensional object displayed on a computer monitor. The computer input device consists of a tracked ball, with a directed source emanating from it, that is housed in an enclosure which allows for the free rotation of the ball. The ball sits on a bearing within a base equipped with an array of sensors. Activated sensors are grouped in such a way that the positions of the detected sources can be determined. A 3×3 orientation matrix is then computed to allow applications programs to present a graphical object in the same orientation as the orientation that the user has given to the ball in the input device.

Claims

1. A computer input device comprising:

(a) a ball with a plurality of directed sources inside arranged so that at least two axes of the ball are distinguished,

(b) a bearing on which said ball rests so said ball may be rotated easily in an arbitrary fashion around any axis through the center of said ball,

(c) a base which holds said bearing as well as a plurality of sensors capable of responding to said directed sources inside said ball,

(d) an enclosure to isolate said sensors from the environment outside said device and keep said ball easily accessible for free rotation, and

(e) interface circuitry to allow a device selected from the group consisting of general purpose computers and specialized electronic processors to read the state of each sensor from the said plurality of sensors,

whereby said device will provide three dimensional rotational control of a graphical object displayed on a monitor,

whereby there is a natural correlation between the movement of said ball by the hand of the user and the three dimensional rotational control of a graphical object, and

whereby said natural correlation is established by absolute measurements of orientation.

2. The computer input device of claim 1 wherein said directed sources are light sources and said sensors are photosensitive devices.

3. The computer input device of claim 1 wherein said directed sources are magnets and said sensors respond to magnet fields.

4. The computer input device of claim 1 wherein said directed sources are colored lights and said sensors are color sensitive sensors.

5. A method of manipulating a three dimensional graphical object comprising:

(a) providing a device containing a ball with directed sources inside arranged so that at least two axes of the ball are distinguished,

(b) providing a bearing on which said ball rests so said ball may be rotated easily in an arbitrary fashion around any axis through the center of said ball,

(c) providing a base which holds said bearing as well as a plurality of sensors capable of responding to said directed sources inside said ball,

(d) providing an enclosure to isolate said sensors from the environment outside said device and keep said ball easily accessible for free rotation, and

(e) providing interface circuitry to allow a device selected from the group consisting of general purpose computers and specialized electronic processors to read the state of each sensor from said plurality of sensors,

whereby said method will provide three dimensional rotational control of a graphical object displayed on a monitor,

whereby there is a natural correlation between the movement of said ball by the hand of the user and said three dimensional rotational control of a graphical object, and

whereby said natural correlation is established by absolute measurements of orientation.

6. A process yielding absolute measurements of orientation from a computer input device containing a freely manipulable ball with directed sources arranged so that at least two axes through the center of said ball are distinguished comprising the steps of:

(a) taking a single initial device reading comprising;

(1) reading raw information from said computer input device,

(2) separating activated sensors of said computer input device into two groups,

(3) mapping the groups of sensors into localized groups of virtual sensors,

(4) averaging the coordinates of the positions of said virtual sensors in said localized groups to obtain current positions of at least two distinguished axes,

(5) normalizing computed data describing the current axis positions,

(6) making a conventional choice of orientation from a group of symmetric possibilities consistent with the computed axis positions, and

(7) storing a mathematical description of said choice of orientation in memory, and

(b) taking subsequent periodic device readings consisting of (1) through (5) as above and then making a choice of orientation consistent with the previous computed orientation thereby discarding symmetric possibilities compatible with the current device reading and then storing a mathematical description of said choice of orientation in memory,

whereby there is a periodically updated 3×

3 orientation matrix to allow applications programs to present a graphical object in the same orientation as the orientation that the user has given to the ball in said computer input device, and

whereby said 3×

3 orientation matrix is determined by absolute measurements of orientation.