Large Binocular Telescope Project
Questions & Answers
concerning the RFP for the
Telescope Instrument Rotator Bearings
April 14, 1999
Question 1. (received 12 Apr 99)
There seems to be an error in the units for the
angular stiffness of the bearings?
Answer 1.
You are correct, the correct units should be "N m / radian".
Question 2. (received 12 Apr 99)
We are having some problems meeting the requested
stiffnesses. Could the stiffness requirements be revisited?
Answer 2.
We have revisited the stiffnesses requested from the
astronomical point of view. We can quote the revised minimum stiffness
requirements as follows. Higher stiffness is always useful.
- stiffness requirements for the Gregorian Rotator Bearings:
- Axial Stiffness > 2e9 N/m
- Radial Stiffness > 2e9 N/m
- Angular Stiffness > 1.2e9 N m/radian
- stiffness requirements for the Nasmyth Rotator Bearings:
- Radial Stiffness > 1e9 N/m
- Angular Stiffness > 8e8 N m/radian
Because of these uncertainties, we have extended the proposal deadline
from 21 April 1999 to 28 April 1999.