CR21 and CR22 rear bellcrank at a 160 lb/in wheel rate.
No part-specific design process is documented. The Bellcranks subsystem design process applies: 1. Take the wheel rate target from kinematics; the bellcrank is named by it (CR26I front is the 150 lb/in wheel rate crank, rear the 200 lb/in). 2. Set the architecture: connection points, pivot location, double or single shear. 3. Size the pivot for shear from the vector sum of rod and damper loads. 4. Run single-plate FEA for deflection first, then stress. CR26I rear single plate at 0.19 in gave FoS 3.54. 5. Calculate the wheel rate change that the measured deflection produces, and confirm it is inside tolerance. 6. Fit and validate the damper position sensor.
The rear load case is much less extreme than the front, so less material is used. CR22's rear bellcrank retains 0.00688 in deflection at 0.2 lb for two plates.
Waterjet from 0.125 in aluminium sheet with connection holes roughed 0.1 in oversize, then finished on the CNC mill to a snug fit. Bushing press fit.
Aluminium.
None recorded. This part has no entry in Knowledge_Transfer/Issue Logging/Fault Vault.xlsx, in either Issue Log.xlsx, in CR22/Issue Tracking/Shakedown 7-15-23.xlsx, or in any design review issue list found in CrimsonStorage or Box.
Nothing in CrimsonStorage covers these yet.