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EQMOD
2011.01.30, 10:56 PM
Here is my latest project, converting a small rc car to 2.4Ghz full proportional control and powered by a 1S Lipo;

http://i263.photobucket.com/albums/ii128/EQMOD/w64_001.jpg

http://i263.photobucket.com/albums/ii128/EQMOD/w64_002.jpg

http://i263.photobucket.com/albums/ii128/EQMOD/w64_003.jpg

View of the electronics including the receiver, and two servo boards acting as proportional throttle control and actuator driver;

http://i263.photobucket.com/albums/ii128/EQMOD/w64_004.jpg

http://i263.photobucket.com/albums/ii128/EQMOD/w64_005.jpg

http://i263.photobucket.com/albums/ii128/EQMOD/w64_006.jpg

As compared to my previous 2.4Ghz conversion;

http://i263.photobucket.com/albums/ii128/EQMOD/w64_007.jpg

EQMOD
2011.01.30, 10:57 PM
Videos:

Proportional control in action;

http://www.youtube.com/watch?v=6tI-5wb-824


Table top run;

http://www.youtube.com/watch?v=F77VgQCTqnU


Floor run;

http://www.youtube.com/watch?v=vbw85CkcJBg

EQMOD
2011.01.30, 10:57 PM
Here she is again with LED lights for the headlight and tail lights;


http://i263.photobucket.com/albums/ii128/EQMOD/ledw72_001.jpg


http://i263.photobucket.com/albums/ii128/EQMOD/ledw72_002.jpg


http://i263.photobucket.com/albums/ii128/EQMOD/ledw72_003.jpg


And a couple of videos;


http://www.youtube.com/watch?v=ek_wBKIPGgE


http://www.youtube.com/watch?v=mhLrnFzlOTs

color01
2011.01.31, 01:42 AM
Saw this on RCTech -- your work is crazy, and awesome. Great! :)

doug01n
2011.01.31, 06:39 AM
Dude.... you are SOOO good doing this crazy things... It's insane!

Congratulations!

Skv012a
2011.01.31, 09:45 AM
Wooooooow! Awesome work!

Guinness
2011.01.31, 11:46 AM
wow that's impressive!

very nice work

sykdevil
2011.02.01, 07:46 AM
Can you share what electronics you are using?

EQMOD
2011.02.03, 09:00 PM
Here are the details of the electronics;

TX - TR2002
RX - RX3002

http://www.efly-hobby.com/en/productlist.asp?id=874

And two Esky 8g servos' control boards used as motor ESC and steering actuator driver. 5kohm pots were added to put the h-bridge output of these servo boards to 0volt;

http://i263.photobucket.com/albums/ii128/EQMOD/potpot_001.jpg

sykdevil
2011.02.17, 09:29 PM
Great work EQMOD

Can you please teach us how to turn the Esky 8g servo into that tiny esc and steering actuator driver? Most interested in how to make that steering actuator driver. The servo to motor esc tutorial can easily be found online, but I never saw one for the steering actuator.

Thanks!

wildthing
2011.03.01, 04:27 PM
I don't want to hijack EQMODs thread... but from what he told me, the actuator will vary its magnetic pull depending on the power it is given.

So if you try to measure the voltage across the wires that are intended for the servo motor, you will notice that the voltage will also vary from zero to about 5 to 6v (depending on power source) depending on the turn of the steering wheel. Sometimes it is lower than that if you set the EPA lower. This is because the signal from the tx is converted to PWM signal that the servo board converts to voltage.

Armed with that explanation from EQMOD, I tried to use a servo pcb to control an actuator of a 1/40th scale Auldey Racetin toy RC.

It did not work properly (very difficult to zero) when I try to center it when I was using a servo pcb from a micro servo (rated 1kg torque - probably similar to the ESKY 8g servo).

However, I had good (probably better) response when I used the servo board from Metal Geared hi-torque servo (from my crawler).

As a conclussion, the magnet in the actuator tends to dictate the type of servo board that will work on the actuator. A powerfull actuator will also require a powerfull servo board.

I think the 1/72 scale car donor that EQMOD used, had a "weak" actuator so he was able to use small servo board from a micro servo.

With regards to the centering potentiometer, you can always use the stock pot from the servo but if you want a smaller one (like EQMOD used) you can try to get surface mount potentiometers with the 5k ohm value (502 is printed on the pot) or a bourns potentiometer (which is easier to get).