05670955 is referenced by 42 patents and cites 5 patents.

A thumbpad input device that enables a user to generate direction and speed by manipulating a round elastic pad. The underside of the pad is lined with a set of uniformly spaced contacts positioned in a circular pattern. Each contact is paired with a corresponding switch that is coupled to a circuit board. When a user presses down on the pad, one or more contacts close their respective switches. The pad contacts and switches are designed so that the number of closed switches varies with the magnitude of the force applied to the pad. The thumbpad input device has a micro controller that monitors the switches. It determines the most clockwise closed switch and the most counter-clockwise closed switch. Presumptively, these two closed switches define the two endpoints of an arc of all closed switches. These endpoints are then forwarded to a host processor. The host processor processes these endpoints to calculate the direction and speed of the symbol which correspond with the user's manipulation of the rubber pad.

Title
Method and apparatus for generating directional and force vector in an input device
Application Number
8/381633
Publication Number
5670955
Application Date
January 31, 1995
Publication Date
September 23, 1997
Inventor
Luis A Reyes
Woodinville
WA, US
John P Pennock
Bellevue
WA, US
Mark T Hanson
Lynnwood
WA, US
Edwin Thorne III
Seattle
WA, US
Agent
Seed and Berry
Assignee
Microsoft Corporation
WA, US
IPC
H03M 11/00
H03K 17/94
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