Patent ID: 8396698

Claim:
A computer-implemented method for simulating the haptic interaction of a tool guided by a user with a virtual three-dimensional object, wherein the tool has a surface and is guided by means of a force feedback device, said method comprising computer-implemented steps, said steps comprising: a) defining a plurality of points P i on the surface of the tool, or at least on the surface of an active region of the tool, wherein the active region is the region of the tool, which can be brought into contact with the object during the method, with vectors n i having starting points at each of the points P i and end points arranged within the tool, said vectors n i are being placed at right angles on the surface and are oriented inwardly, b) defining a copy of the tool as a proxy, said proxy being an identical duplication of the tool, at least with reference to the points P i and the vectors ni, c) defining a position of the tool by a tool center point (TCP) and a position of the proxy by a proxy center point (PCP), d) defining a starting position of the PCP at a time T −1 for which no end point of the vectors n i , has contact with the object, e) bringing the tool into contact with the object comprising penetration of the object, thereby forming a position of the TCP at a time T 0 , f) determining a new position of the PCP at the time T 0 from the position of the proxy at the time T −1 and of the tool at the time T 0 , by determining the PCP at the time T 0 intermediate on a connecting line between the PCP at the time T −1 to the TCP at the time T 0 and at a distance from the PCP at the time T −1 of maximal one length of a vector n i or of a fraction of one length of vector n i , wherein the distance is defined as displacement length l, g) wherein determining the new position of the PCP at the time T 0 is made by means of a case-by-case analysis as follows: g.1) if at least one end point of a vector n i of the proxy dips into the object at the position of the PCP at the time T 0 intermediate , the position PCP at the time T 0 is defined as position PCP at the time T −1 , otherwise, g.2) the vectors n i are scanned until a point of intersection with the surface of the object is found, which results in penetration depth vectors s i between points P i and the point of intersection and the penetration depth vectors s i have a direction of the vectors n i , a reset vector s is computed from the penetration depth vectors s i , wherein the direction of the reset vector s results from a sum of the penetration depth vectors s i and PCP T 0 intermediate is displaced by the reset vector s and results in PCP at the time T 0 , and h) the force feedback device exerts a force in the direction of TCP at the time T 0 to PCP at the time T 0 .