To provide the primary structure of the vehicle and the interface between that structure and the driver. Chassis owns the welded 4130 space frame, the impact attenuator and anti-intrusion plate, firewalls and floor panels, and the entire driver interface: seat and seat insert, headrest, harnesses, dash panel, pedal box, steering system from wheel to rack, and the paddle shifters. The frame is the datum every other subteam mounts to, so Chassis drives packaging more than any other subteam.
- Hit the torsional stiffness target that keeps the platform's roll stiffness close to an infinitely stiff frame. CR26I target 1736 lb-ft/deg (90.2% of infinite), actual 2140 lb-ft/deg. CR26E target 1651 lb-ft/deg, measured 1995. - Keep frame mass flat or falling while stiffness holds. CR26I net tubing change was -1.16 lb against CR22. - Manufacture to CAD. CR26I average node deviation from CAD was 0.101 in total (front 0.110 in, rear 0.091 in), verified with a FARO arm; outliers were fed back into the kinematics model. - Accommodate drivers from 5th percentile female to 95th percentile male on every control, verified through anthropometric study and EMG fatigue testing rather than opinion. - Egress in under 5 seconds, no snag points, shielded rotating and hot components. - Reduce driver fatigue over a full endurance stint. EMG mean-frequency shift is the measured quantity. - Improve serviceability: CR26I cut pedal adjustment time 60% (3:00 to 1:45) and eliminated the need for tools.