I need help with my first attempt at creating an RC car. Details are in post, all help is welcome.

Thread Starter

Correndell

Joined Dec 3, 2017
3
Alright, so lets get started:

Hello everyone! If you're reading this, I appreciate you taking the time to read the post.
Quick introduction: ETN1 in the Navy who just recently joined this forum in the hopes that with all the collective brainpower I may be able to get this project off the ground since I have very little in experience with this kind of thing. I know it may seem crazy, but the Navy really frowns upon people trying to actually repair electronics, so I'm taking this upon myself to get some experience.

Here's what we're working with: I have this *giant* Toy car..it's a Fire Truck from American Plastic Toys Inc. The measurements are 22 inches long, 12 inches wide, and 14 inches tall. The wheels are 6 inches in diameter, with a very hefty steel rod as the axel to both front and rear wheels.

Space is not a concern, there is a massive amount of under-carriage clearance and there's is a compartment inside that can be open and shut that will also allow further room.

I have done some research on how I would like to accomplish this, but my preference is to go with as much second-hand and DIY as possible, instead of buy some already complete kit and just installing it. Hence the desire to gain experience.

The parts I'm working with: I have a 14.4V DC motor, All of the internals to a Dirt Devil BD10315B Handheld Vaccum Cleaner (NO issues with electronics or motor, just Black Mold grew on the impeller, so it became more of a biohazard than anything. Two of the batteries did short however during dissasembly, so I only have two 18650 batteries left, but I will gain two more.

The Circuitboard to the Vaccum Cleaner had a LGFT4101V5 circuit board, which I believe has both battery monitoring/control, a thermal sensor ( To check for battery overheat), a built in fuse, and attachments for the on/off switch (Which I do still also have).

What I would like to know is what would be the best way to use what parts I have on hand to make the RC car? Or did I just list off a bunch of useless stuff with the exception of the battery and motor, and I should get an Arduino kit? I know I'll still need a servo motor for the front wheels, but I am concerned if a 14.4v motor is either too big or not enough for this toy (it is extremely lightweight though, even from a toy's perspective. Just a giant plastic thin shell).

As for the controller. I've done some looking up, and it seems a Arduino based controller with programmable settings can help me control future projects without having a dedicated controller at first.

Alright, that's all I've got. Appreciate the help, and all ideas are welcome.
 

Alec_t

Joined Sep 17, 2013
10,601
Welcome to AAC!
If 'RC' means 'radio control', not just 'remote control', then apart from what you've listed you are going to need a legal off-the-shelf radio transmitter and receiver.
Do you want speed and forward/reverse control for the motor?
 

rthomas12

Joined Dec 6, 2016
32
I would start by using the makeablock MBot as a tool to learn from and a controller for your project. It even has an app to control your project from a smart phone. I am using it to control 24volt motors with Gitfun RFP30N06LE transistors.
 

Thread Starter

Correndell

Joined Dec 3, 2017
3
Speed would be nice, and forward/reverse is also desired. I guess my statement is what would be the most appropriate method. I've been having a hard time finding a Radio Transmitter/Receiver that are not just more expensive than a RC car itself.
 

Thread Starter

Correndell

Joined Dec 3, 2017
3
Ok, here's what I've come up with so far, and some actual application of circuit design would be great vs the mechanical design.

I bought a small cheap rc car from Goodwill, and stripped the receiver from it. From what I gathered the battery pack exploded, but I assume the reciever is fine. The transmitter is missing, but I can deal with that in my own time.

The voltage rating is 7.2v, but I want to use a 14.4 v motor on it. Would it be possible to use an operational amplifier comparator to be able to control a 14.4 volt motor with a 7.2v rated receiver? I understand the voltage supply would need to be a 14.4 voltage supply, but I am wondering if it would be possible to have both a forward and reverse comparator for a forward and reverse control on the motor.

More inputs would be great.
 

Alec_t

Joined Sep 17, 2013
10,601
There are loads of motor speed control modules available online. You would need to check their specs to see what the input and output requirements are and if they are compatible with your receiver. The receiver may have proprietary outputs rather than standard servo signals.
 

be80be

Joined Jul 5, 2008
1,961
The Vacuum Cleaner motor is useless it will never power a wheel without tons of gearing it's to fast.
Find you one of these. great motor in it
 
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