Need some help and suggestion

[hanhoong]

Hi all,
I'm a business study student, therefore I'm a begginer on mechanics and electronics. However, I'm interested to build a RC car to help transport things. I'm glad that you all can provide me some advice on choosing parts and products.
Requirements:
- A wireless control for 20m to 50m.
-4 dc motor with speed controllable with carrying around 20 kg load. ( slow speed is ok ).

[ABSF]

Hmmm... A RC car able to carry a load of 20Kg and has to move a distance of 20m-50m.....

What is the size of the load? Was it as big as a luggage (use for travelling by air)? Why it has to be a car? Can it be a piece of 3'x3' plywood with motors mounted on the underneath? Does it has to be able to avoid obstacles? Does this "car" has to go past a wall so you cannot see it while it is travelling?

Are you doing this project to learn electronics, programming, mcu Or just want us to recommend you a product that can do the work for you? Being "Engineering", all these have to be defined clearly. Otherwise you might not get what you wanted and instead wasting your money getting something that's useless to you.

Allen

[hanhoong]

Thanks Allen

Ya, is just a simple like 3'x3' plywood with motors mounted on the underneath. I choose to use remote control is because that i think by involving sensor may be too complicated for me.
I do this is to learning programming and electronics, but beside it, I can also use it to do something else as well.

[hyng]

Hi, you can use this powerful motor http://www.cytron.com.my/viewProduct.php?pcode=9DCP24-120-30G&name=120W%20DC%20Brush%20Motor
It can at least carry a person weight, we have tried it before.
For motor driver, you can use MDS40A http://www.cytron.com.my/viewProduct.php?pid=NiUbHwoPAAgMBQUEOQA0MtWhikPpCDyhE6jJKUfzpVw=
It can be control with RC.

[ABSF]

The 4 motors would cost you well over RM 2K. I was thinking about using the windshield wiper motors for cars but I am not sure if they are geared and the mounting would be complicated. The high current consumption is also a problem. You might end up 1/4 of the space on your plywood is used for the wet cells.

Since you are doing it for learning programming and electronics, you can do it on a scaled down model, say a payload of 500gm. In that case the cost of buying the motors would be very much reduced. You can divide your project into 3 parts:

1. The RC part which will send siganls to control LEDs using a keypad or joystick.
2. The control of speed of motors using speed controllers and how to change directions of your plywood.
3. The interfacing of the RC receiver and the steering of the motor.

After mastering the above concepts, you can then proceed with your final model.

Allen

[hanhoong]

thanks hyng and Allen.
After, I had read your comment, I know my direction more clearly.