Friction compensation in a minimally invasive surgical apparatus
US6565554B1 · kind B1 · utility
Assignee
Inventor
Key dates
| Filing date | Apr 7, 1999 |
| Grant date | May 20, 2003 |
| Priority date | — |
| Expiry date | Apr 7, 2019 |
Classification
- Technology area (CPC A)Human Necessities
- CPC primaryA61B2034/305
- WIPO fieldMedical technology
- WIPO sectorInstruments
Abstract
The present invention provides improved devices, systems, and methods for compensating for friction within powered automatic systems, particularly for telesurgery and other telepresence applications. The invention allows uninhibited manipulation of complex linkages, enhancing the precision and dexterity with which jointed structures can be moved. This enhanced precision is particularly advantageous when applied to the robotic surgical systems now being developed. The friction compensation systems of the present invention address static friction (typically by applying a continuous load in the direction of movement of a joint) and the often more problematic static friction (generally by applying alternating loads in positive and negative joint actuation directions). The invention can accommodate imprecise velocity measurements by applying an oscillating load whenever the joint velocity reading falls within a low velocity range. Preferably, the oscillating load is insufficient to move the joint without additional input, and significantly reduces the break away input required to initiate movement. In the exemplary embodiment, a duty cycle of the oscillating load varies, favoring the ap…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.