Gryo Screwdriver RC control?

[eojreyem]

First time poster and I'm asking for help...

I came across the Gyro 4V Max Black and Decker Screwdriver on clearance and have been trying to figure out how to use them to drive a small combat robot. Teardown w/ Pics!

Since they are controlled by a gyro I figured they already have most of the circuitry I'll need to drive the motor. I bought one and opened it up.

There's an H bridge made from 4899NF Mosfets
And a H bridge driver IC 83202IBZ

I think bypassing the Gyro and MicroController from the screwdriver should be possible, and instead input a PWM signal from my RX?

Can anyone point me to information I'll need to convert the signal from my RX into a PWM signal for this H-bridge driver? It does need to be converted, right?

FYI: thinking of using this TX/RX

[harry hills]

Hah I've been playing around with one of these at work recently I did wonder if they had any use for other stuff.

Good luck with your project. It sounds like a lot of work to get anything as good as an off the shelf product but if you enjoy it then good on you

Harry.

[eojreyem]

I have a very rusty degree in Elec Engineering. So it's not completely foreign to me. But yeah... trying to gauge how challenging it'll be and if my goal is to simply save a few bucks it may not be worth it.

Looking into giving it an Arduino brain and giving it remote control via other wireless tech.

[eojreyem]

A bit more research shows I need some sort of signal processing between the RX and the PWM signal for the motor driver circuit.

The signal from the RX is a PWM signal where the length of the high pulse is what's important (example: 150ms long pulse is neutral or half way on servos. 100ms pulse is the shortest (or all the way one way on a servo) and 200ms is longest (all the way the opposite way). There is then a low pulse for some time after it.

The signal the motor driver circuit needs is a PWM signal where the duty cycle of the pulses is important. If the pulse spends 50% of the time up and 50% down it will drive the motor at half speed. 75% up/25% down the motor is at 3/4 speed.

I'm thinking of buying an Arduino Uno for this task.

[marto]

You could probably reprogram the Xmega on the board to read in those signals and control the ESC but it would take a bit of effort and I have never used the Xmega variety from ATMEL before so not sure how hard that would be to get up and running.

Looks like there is pads on most of the Pins you would need to access if you wanted to do it.

Steve

[Max]

I've converted the PPM signal from an rx to PWM to directly drive a small motor, there is plenty if open source code to do this.
I would recomend an arduino mini for use in a robot rather than an arduino uno, it is much more rugged and compact but less good for prototyping as it doesn't have the "push in wire connectors" but instead you solder the wires in so it is more for final solutions than prototyping.