|
05.19.2007, 08:38 PM
Simple and short, my opinion on braking.
BL motor braking: (most likely mechanics)
first: a shorted motor has incredible resistance from turning, and, the faster it spins, the more resistance it has.
- Using full motor shorting for braking would undoubtedly flip an R/C car over it's lid with ease.
- So, you need to control this shorting in order to control the motor shaft resistance, to create an average resistance or torque.
-Along came PWM... the controller sets up the FET's to unify all motor phases to create a short. So the controller will change PWM duty cycle depending on throttle position... so anywhere between say 1% to 95% (for ABS, guessing) duty cycle for proportional braking.
-These latest controllers (like the Quark) most likely have some good algorithms for braking.
This is just my simple theory on motor braking, not going into detail what happens in FET's.
:025:
“The modern astrophysical concept that ascribes the sun’s energy to thermonuclear reactions deep in the solar interior is contradicted by nearly every observable aspect of the sun.” —Ralph E. Juergens
|