Motion control system for the Large Optics Diamond Turning Machine (LODTM)
LODTM, built by LLNL for DOD, is a precision vertical lathe used to diamond turn large optical parts (to 64'' diameter) to 1 ..mu.. inch tolerance. The LODTM motion controls require precision sensors, precision servos, and a wideband (100 Hz) real time computer. Position is sensed to 1/40 ..mu.. inch resolution by laser interferometers and differential capacitance gauges. Precision servos operating at 1/10 ..mu.. inch resolution and at low velocities with zero backlash are required. A unique fast tool servo (FTS), located close to the diamond tool, adjusts the final tool position. The LODTM controls coordinate the X, Z, and FTS servos to cause the tool to move on a specified contour and at a specified feedrate in the X-Z plane. The part tape commands this motion with a linear CNC and real time (32-bit) computer. During each 1 ms sample time, the computer must DMA 13 sensor readings into memory, calculate the X and Z Tool Coordinates, calculate the FTS input, output the following errors, output the FTS input, and check for anomalies.
- Research Organization:
- Lawrence Livermore National Lab., CA (USA)
- DOE Contract Number:
- W-7405-ENG-48
- OSTI ID:
- 5709996
- Report Number(s):
- UCRL-86438; CONF-8110142-1; ON: DE82006740
- Resource Relation:
- Conference: Instrument Society of America conference, Anaheim, CA, USA, 6 Oct 1981
- Country of Publication:
- United States
- Language:
- English
Similar Records
Lawrence Livermore National Laboratory ULTRA-350 Test Bed
Lawrence Livermore National Laboratory ULTRA-350 Test Bed