Method for scanning the surface of an object
US5499194A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Mar 31, 1994 |
| Grant date | Mar 12, 1996 |
| Priority date | — |
| Expiry date | Mar 31, 2014 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG05B2219/34101
- WIPO fieldControl
- WIPO sectorInstruments
Abstract
A workpiece surface 30 is digitized by scanning it with the stylus 8 of a scanning probe 5. Digitized coordinate data for many points P1-P6 on the workpiece surface are subjected to a filtering algorithm, in order to remove redundant data when the surface is relatively flat or planar. Top and bottom tolerance vectors TV0,BV0 are defined, starting from a first point P1 and lying at a given tolerance h above and below a second point P2. Next, a direct vector DV1 is defined between the point P1 and a third point P3. If the vector DV1 lies outside the tolerance band between the vectors TV0 and BV0, then point P2 is deemed to be required and is not filtered out. Otherwise, the data for point P2 is deemed to be redundant and is rejected. In this case, new tolerance vectors TV1 and BV1 are now defined, starting from point P1 and passing within a tolerance h above and below point P3. From the four vectors TV0,TV1,BV0,BV1, a pair of vectors TVn,BVn is selected for a further iteration of the process, based upon which of these vectors lies closest to the vector DV1.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.