Granted Patent B2

US 12,623,272 · App. 17/353,100 · Granted May 12, 2026

Inventors: Friedrich Riemeier (Berlin, DE); Werner Butscher (Berlin, DE); Frank Witte (Berlin, DE); Christoph Radinger (Teltow, DE); Andrew Cordell (McKinney, TX); Rohit Sachdeva (Plano, TX)

Assignee: Dentsply Sirona Inc.

B21F45/008A61C7/002A61C7/20B21F1/008B21F23/005B25J9/1682B25J9/1692B25J9/1697G01B11/24B21C51/00Y10T29/49568

Abstract

Claims (18)

1 . A method of calibrating a bending apparatus comprising at least a first moveable manipulator and at least a second moveable manipulator, comprising the steps of:

positioning a wire such that it is held by the first moveable manipulator and the second moveable manipulator, wherein the first moveable manipulator includes at least one revolute joint defining a first rotation axis and at least two prismatic joints defining a first translation axis and a second translation axis, and wherein the second moveable manipulator includes at least two revolute joints defining a second rotation axis and a third rotational axis;

moving the first rotation axis, included as part of the first moveable manipulator, measuring movement of the first rotation axis, measuring a first resulting movement of the wire, and recording the first resulting movement;

moving the first translation axis, included as part of the first moveable manipulator, measuring movement of the first translation axis, measuring a second resulting movement of the wire, and recording the second resulting movement;

moving the second rotation axis, included as part of the second moveable manipulator, measuring movement of the second rotation axis, measuring a third resulting movement of the wire, and recording the third resulting movement;

moving the second translation axis, included as part of the first moveable manipulator, measuring movement of the second translation axis, measuring a fourth resulting movement of the wire, and recording the fourth resulting movement;

moving the third rotation axis, included as part of the second moveable manipulator, recording movement of the third rotation axis, measuring a fifth resulting movement of the wire, and recording the fifth resulting movement;

developing a real model based on the recorded movements of the axes of the first moveable manipulator and the second moveable manipulator and the corresponding recorded movements of the wire; and

iteratively bending and measuring single bends in the wire until correct overbending values are determined for the wire;

wherein each of the axes of the first moveable manipulator and the second moveable manipulator are moved in different directions, wherein the resulting movements of the wire are measured by a vision system, and wherein measuring the resulting movements of the wire comprises using the vision system to measure the wire shape while rotating the wire about the first rotation axis to reconstruct both the actual wire cross section and actual bend formed in the wire.

2 . The method of claim 1 , wherein the vision system is configured to measure the wire shape after each bend is completed, and wherein the measured wired is used to calculate grip positions for subsequent bending operations on the wire.

3 . The method of claim 1 , wherein the wire is made from an alloy.

4 . The method of claim 1 , wherein the wire is an orthodontic archwire.

5 . The method of claim 1 , wherein developing the real model comprises:

calculating joint values based on a planned bending position;

calculating an actual achieved bending position;

comparing the actual achieved position to the planned position; and

if the difference exceeds a limit, defining a new target position by adding a compensation movement to the planned bending position.

Continuity (5)

References Cited (72)