Crimson Racing Wiki

Seat

Subteam: ChassisSubsystem: ErgonomicsAssembly: SeatCars: CR21, CR22

Purpose

The structural shell the driver and the seat insert sit in.

Function

Provides the base geometry the insert is molded against, and carries the driver's weight into the frame.

Design Process

No part-specific design process is documented. The Ergonomics subsystem design process applies: 1. Take driver body measurements and place them against the ergonomics study ranges. 2. Mold the seat insert to the driver in the car with expanding foam, then hand post-process and cover. 3. Set headrest and harness mounting to the rules and to the driver's shoulder height. 4. Run a simulator or on-track endurance stint and measure fatigue with EMG. 5. Iterate the insert shape at the identified pressure and support points.

Analysis

Validation has historically been by lap delta, which the one-pager says has "more than proven the need for a seat", plus driver feedback and weight.

Manufacturing Process

CR22 logged time per seat: 1 hour of prep, 1 hour to pour and cure, 2 hours to refine and post-process. CR22 materials: mattress bag $12.99, two-part foam mix $75.99, tape $9.58. The CR25 design added a solid carbon back to decrease seat profile and increase stiffness, with the same two-part foam mixture retained because the alternative Creafoam product costs $380 for a 25 gallon bag.

Full Material List

CFRP, Nomex sandwich panel on CR26I.

Reoccuring issues

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.

Properties

Chassis weight breakdown: CR25 3.300 lb, CR26E CAD 2.436 lb. CAD mass, CR26E master assembly: 2.436 lb (1.105 kg). CG at X 51.95 in, Y 0.00 in, Z 11.99 in in vehicle coordinates. Source: CR26E/Systems/03 - Mass Model/ChassisWeightBreakdown.xlsx | SolidWorks mass model exports: CR22 (5 May 2024), CR25 (4 Jul 2025), CR26I (30 Jul 2025), CR26E (22 Mar 2026) Quantity per car, as costed: 1

Still to document

Nothing in CrimsonStorage covers these yet.