Synthetic friction algorithm for a hand control element
First Claim
1. A method for simulating friction forces in an active, position mode hand controller that includes a hand-control element and a motor coupled to said hand-control element, said method comprising the steps of:
- establishing a reference position;
establishing a static friction zone having a static zone boundary that extends a short distance on either side of said reference position;
linearly increasing a force toward said reference position applied by said motor to said control element as said hand-control element moves from said reference position within said static friction zone;
maintaining a constant force toward said reference position applied by said motor to said control element as said hand-control element moves from said reference position outside said static friction zone; and
redefining said reference position when a position of said hand-control element crosses said static zone boundary of said static friction zone, by translating said static zone boundary closest to said position of said hand-control element, to said position of said hand-control element.
1 Assignment
0 Petitions
Accused Products
Abstract
Synthetic friction force algorithms provide simulated static friction forces as well as dynamic friction forces. On either side of a hand-control element reference position a small static friction zone is established. As long as the hand-control element is within this static friction zone, the reference position remains constant and the control element drive motor generates a centering force proportional to the distance of the hand-control element from the reference position; a force urging the hand-control element toward the reference position. When the relative position of the hand-control element reaches or exceeds an edge of the static friction zone, it enters the dynamic friction zone. The motor applies a constant dynamic friction force, urging the hand-control element toward the reference position and the reference position is translated so that the edge of the static friction zone is translated to the current hand-control element position.
24 Citations
3 Claims
-
1. A method for simulating friction forces in an active, position mode hand controller that includes a hand-control element and a motor coupled to said hand-control element, said method comprising the steps of:
-
establishing a reference position; establishing a static friction zone having a static zone boundary that extends a short distance on either side of said reference position; linearly increasing a force toward said reference position applied by said motor to said control element as said hand-control element moves from said reference position within said static friction zone; maintaining a constant force toward said reference position applied by said motor to said control element as said hand-control element moves from said reference position outside said static friction zone; and redefining said reference position when a position of said hand-control element crosses said static zone boundary of said static friction zone, by translating said static zone boundary closest to said position of said hand-control element, to said position of said hand-control element. - View Dependent Claims (2, 3)
-
Specification