Real DIY RC Car : 7 Steps

Hello again all my dear friends.

Today I am going to show you how making RC Car which control with RF module. I'll try my best to give you all detail.

Okay, let's get it started.

My goal in this project was to make an RC car fully by myself and make a custom controller for it.I also made the body and chassis by myself.I tried my best to build it as light as possible, so I can run it faster.

Step 1: Get the Parts and Tools

Guys you may think that a lots of materials used in this project but it's fully customizable and you can do any change you want.

Materials:

1.solid gardening wire

2.rf module(433 Mhz, I leave the link to where you could buy it)

3.pcb

4.HT12E encoder

5.HT12D decoder

6.1 mega ohm, 51k ohm, 150r, 220r resistors

7.bc547 transistor

8.two lm7805 voltage regulator

9.two 10uf and two 100uf capacitor for voltage regulators

10.1000-3900uf capacitor (use to filter the rf module voltage)

11. irf530(2), irf9530(2) mosfets for back motor h bridge driver.

12.heat sink(for mosfets)

13.fan( I used small 5v fan to make sure all system stay could)

14.old ps or xbox controller( I had few broken ps controller and I used them)

15.servo

16.DC motor( I salvage it from a old printer and it work perfect)

17.two 0.1uf ceramic capacitors for motor and servo

18.female header

19.few different color leds

20.two 18650 li ion battery, I used them in series to get 4.2v with higher current(optinal)

21.a DC DC boost conveter (to convert the battery voltage from 4.2 up to any voltage you want)(optinal)

22.18650 battery charger

23.power jack

24.l293 or l298 h bridge ic

25.small digital volte meter

26.1/10 size rc car wheels(4)

27.1n4007 diode(4)

Tools:

Soldering iron

plier

wire cutter

etc

Step 2: Start to Assembling

You can find the datasheet for HT12e and HT12d by searching in google and it is very simple circuit.

As you can see I made a HT12 E encoder circuit on a small piece of PCB and then I connect the HT12E output with very thin wire to the switches, transmitter, antenna and filter cap. I take all the inside parts of ps controller out and attached a momentary switch to the rubbery part of the controller. HT12 E need 5 volts to operate so I used smd lm7805 to get smaller space and fit easy. the controller assembly is much easier than the car. after I assembled all the parts I put the controller together.You can see photos and get and idea how to do it.

Step 3: Making the Car

I used 2mm gardening wire to make my car body.I belive it's very simple and easy to make the back chacies and the front.

I made the spring shape wire to cross the back wheels and make it easeir to be stable and turn smothly.then I made another spring shape for front wheels but in vertical with a cross between two spring. I leaved few photo of it for you to give you an idea about how you can do it.Do not use too thin wire because it may bend easy and your car body not look nice. for the wheels I used the 1/10 size rc car wheels that you can buy them for 8$ from ebay and you can choose any wheel you want.(The back wheels are attached togeather by pice of Stainless Steel 303 201 Round Solid Metal Bar Rod Dia 4mm Length 155mm which is very strong and smooth).

For the electronic part I used HT12D decoder and a mosfet h bridge for running the back motor and l293 for running the servo.Two output of the decoder send signal to mosfet h bidge and two of them connect to l293 h bridge.

The h bridge circuit is very simple and easy to make. I used two npn and two pnp mosfets. I will upload some photo of the circuit for you. the reson for using a h bridge for back motor was to push it as much as possible to run a motor faster and faster(I feed the h bridge now with 24v and 1a) and it work very nice and smooth and my car run faster and faster. I also used a small 12v fan to cool down all the system.

This is link to the mosfet h bridge circuit:

(https://en.wikibooks.org/wiki/Practical_Electronics/Stepper_Motors)

for front wheel I used a metal gear 9g servo. I opend a servo and solderd two wire to the inside motor to be able to run it as dc motor very nice and simple. To run the servo I used l293 h bridge with 12v and it work nice and smooth as well. see the photo of how to use a servo as a dc motor.(you can use plastic gear servo as well but I used a metal gear one because it is stronger)

Step 4: Making a Battery Pack

As I said before, I used two 18650 li ion battereis in parralel to get higher current and I used a DC DC boost converter to boost the voltage from 4.2v of the batteries to any voltage I want(I boost it up to 24v). you can see the photo of the boost converter and you can buy it from ebay for 6$ and it is very stable and work perfect. I attached a charging madule with the switch to the batteries, you need to add the swith to the circuit, because durring a charging the circuit shouldn't operate and the switch cut of the connection to the circuit.I also used a small digital volt meter on the boost converter output to monitor the output voltage at all the time. My own made battry pack oparate at list for 2hour continuously without any problem.