...
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).
Parking Brake Specs
Assumptions
-5/32" disc thickness (3.9mm)
-8" rotor diameter
550kg total car mass (including ballasted driver & passenger)
Requirements
ASC:
Hold 10% of cars weight in fully loaded position on dry pavement
WSC:
Hold car on a 20% incline or decline (approx. 11.3 degrees)
Calculations
ASC
Braking Force = Pulling Force - Friction Force
= (0.1)(9.81N/kg)(550kg)
= 539.55N
WSC
Braking Force = mgsin(θ)
=(9.81N/kg)(550kg)sin(11.3)
=1057.22N
Required braking force is driven by WSC requirements.
Performance data for Tolomatic Mechanical Brakes. Static torque data is to be used.
Braking radius for an 8" disc = 3.376" = 0.08575m
Braking Torque = (Braking radius + wheel radius)(Braking Force) = (0.18738m)(1057.22N) = 198.1Nm
Since there are two parking brakes, torque required per brake = (198.1Nm)/2 = 99.05Nm
Maximum static torque for ME10 is 226Nm. If we order a 3.5" lever, will need between 75-100lbs of lever force.
