Parking Brake MSXV

Objective	Design a Parking Brake for MSXV that satisfies ASC and WSC regulations
Key outcomes
Status	IN PROGRESS

Problem Statement

Design MSXV’s Parking Brake, ensuring that it meets all regulations as imposed by ASC and WSC

🎯 Scope

Must have:	Rotors must have a diameter from 6.00” to 13.00” Rotors must have a thickness from .25” to .81” Actuating lever (to connect caliper to brake cables)
Nice to have:	Hang caliper on center, or very close to center of rotor Mounted at 10-11 o'clock position Design caliper bracket mount
Keep in mind:	MSXII’s parking brake failed to meet FSGP requirements for minimum stopping distance Parking cables have a minimum bending radius of 6”
Need to figure out:	Narrowness of car How brakes (caliper portion) will be mounted Do we want a stick vs center lever parking brake (center lever recommended) How do brake caliper assemblies work Lever force Lever design
Caliper Carrier (Keep in Mind)	Adjustable tabs Caliper carrier connected to suspension mount (one part) Suspension shouldn’t interfere with caliper body

Given Parts

Parking Brake Parts

Part #

QTY

Catalogue URL

Specs

Wilwood Caliper (Parking Brake Caliper)

120-1360

2

https://www.wilwood.com/PDF/Flyers/fl13A.pdf

Brake Pad Info Sheet

https://www.wilwood.com/BrakePads/BrakePadsProd?itemno=150-13675

Single piston, floating caliper
Has a cam-actuated lever
Two settings for leverage adjustment
Brake pads designed for this caliper are discontinued (no info)

Parking Brake Cable Kit

330-9371

1

https://www.wilwood.com/PDF/DataSheets/ds1108.pdf

Cable’s should be routed as straight as possible, minimum bend radius of 6”

\uD83D\uDD17 Reference materials

ASC Regulations

10.6 Parking Brake Solar cars must be equipped with a parking brake.
10.6.A Performance The parking brake shall be able to hold the car in place without wheel chocks on dry pavement under either a forward or rearward force equal to 10% of the cars weight in fully loaded condition.
The parking brake should be able to hold the car in place when pushed with a force equal to 10% of the cars weight (a.k.a if car’s weight is 100N, it should be able to withstand 10N of force)
10.6.B Independence This brake must operate completely independently from the main braking system and may not be used in the performance tests specified in Reg.10.9.D.
10.6.C Locking
- 10.6.C.1 It must be able to be locked into the “ON” position, such that the driver does not have to continue to hold it to maintain position.
- 10.6.C.2 The driver shall be able to set and lock the parking brake while seated in the normal driving position and seat belted in.
- 10.6.C.3 The driver shall be able to set and lock the parking brake in a single action or motion.

“lockable, independent equipped with working parking brake (must hold 10% of vehicle weight in both directions), non-tire contact style”

10.6.D Contact Style
The parking brake shall not be of a tire or wheel contact style (i.e. pad on tire or pad on rim styles are not considered as acceptable designs).

WSC Regulations

2.21.10

Solar cars must be equipped with a parking brake that can be operated by the driver from the normal driving position. The parking brake must hold the fully laden solar car on a 20% incline or decline.

Reference Information