quantumflop

I am wondering if anyone has tried hacking an ESC. I know that the E-Flite 20Amp ESC has pads on the circuit board corresponding to the in-circuit programming pins of the Atmel processor. I'm thinking that it may be possible to burn the Atmel EEPROM with custom code. The Hyperion Titan 10A does not have the pads, but it appears that the ISP pins are not in use. Which, at least, leans toward the possibility that the Atmel is not fused to disable in-circuit programming.

Well, el gurus? Anyone have some info?

Matt Kirsch

My Feedback: (21)

Wow, you're way more into this than I could ever hope to be.

Just out of curiousity, what would you be looking to improve over the stock programming?

quantumflop

The stock programming uses a startup code that is fairly routine in sensorless BLDC motors, i.e., they energize a winding to put the rotor into a known electrical position, then start guessing at the communation timing until they get the rotor up to a speed where the back EMF signal is sufficient for a commutation trigger. This startup technique frequently requires the motor to rotate "backward" to its starting position (not always desireable) and has horrible torque capabilities. A paper and patent from about 11 years ago, meaning it is nearly public domain now, provides a technique for sensorless BLDC startup that pings the windings in a predetermined pattern in order to determine the rotor position using the inductance saturation of the stator. This technique provides nearly an exact rotor position when compared with using Hall effect sensors and, as such, can provide optimum startup of sensorless BLDC motors. I'd like to try to implement that technique using a hobby ESC.

-pkh-

My Feedback: (2)

I think the Castle Creations ESCs would be more easily hacked, since they use a USB interface to program them, and to upgrade the firmware.

BTW, an 11 year old patent is not even close to public domain. They expire 20 years after the filing date, which is typically 17-18 years after the issue date.

quantumflop

Oops. You're right about the 20 year patent term. I should've known that. Oh, well, I wasn't going to try to peddle the technology anyway. I just wanted to use it myself.

As for the Castle Creations ESC, you may be right. I'll give it a try. Thanks!