First Conversion: Bruder Delta Loader

[RobotArms24]

So this will be my first attempt at converting a toy to R/C. I have spent some time researching other peoples conversion and have come up with a game plan. I chose a skid steer because they are pretty simple and I always wanted a skid steer.

I saw on another forum someone had used an embedded computer to control his skid steer, and this idea intrigued me. I decided the extra cost for the microcomputer was not worth it tough, and my programming knowledge is very limited because I haven't done any programming since I was in high school.

So the plan for now is to use gear motors and the sabertooth motor controller. Hobby King has some cheap receivers and transmitters that I will use to control the loader.

I have already ordered my loader and ripped it apart. We have all seen pictures of them so I wont post any. I did break most of the tabs when disassembling, and I have no idea how anyone can disassemble these toys without breaking them...

Here is a short parts list I have going:


The lift servo is a servo I have lying around already so I figured I will give it a shot. It's almost 15kg/cm so it should be more than strong enough.

The bucket servo is a "robotics" servo that should be able to do 180 degrees, and should have lots of power. I saw on the other forum that one guy had a full size servo on his bucket and had made a 3D printed mount for it, that anyone can buy, so I will try that.

I drew up a wiring diagram:


I have two BEC's on there, but I don't know if it is necessary.... The motors are I believe 800 mA stall and I can't find specs on the servo's, does anyone know roughly how much power a servo will draw? I might end up just getting a single larger BEC to control everything, it would probably make less interference that way as well.

These are the motors I plan to use:
https://www.pololu.com/product/1594


According to my measurements they should fit great. They are the slowest RPM they make in that style at 80rpm@4.5V, and I will run them at 6V so I hope they aren't too fast.

They make nice looking motor mounts for these motors.



I have been working on some 3D models for drive hubs. I can send them to get 3D printed in Nylon for really cheap. I had test printed my first design at a local printing hub and they turned out not too great, the local printer was very low resolution.


I have a newer model I will get printed by shapeways. I have seen pictures of their prints and they are much higher quality and still afforable. The problem with shapeways is the looong wait time, something like 30 days to print.

Here is what I have so far:

The recess in the back is for the shaft adapter.

This is what the real thing looks like, I tried to make it realistic looking.



This is my progess so far, and it will probably be a bit of a long project, work is slow so r/c money is limited.

Any thoughts/suggestion would be greatly appreciated!

Thanks for looking!
-Kyle