4WD Arduino Car

To anyone reading this who is a developer, or an electrical engineer, or one of those weird people who is a bank teller or something as their day job, but also tinkers in their garage and somehow knows out how to build a 3D printer or something, you may think this is lame.

But I am not a developer. I don’t know how to code. I know almost nothing about circuit boards, or installing bluetooth, robotics, etc. So to me, this project is one of the more interesting projects I have done, with the most opportunity to learn. It also happens to be one of the more daunting projects I have started. The instructions clock in at 166 pages. I appreciate the instructions though, because on top of showing you how to put the car together and make it work, it explains how what you are doing actually works. Here is an example:

Assembling the car

Below is the full list of parts used to build the car. The bags at the top left are the various different screws and stands used for the car itself. The wires next to it are for connecting the different control boards and LED lights. To the right of the wires is the battery pack and USB cable for connecting the car to your computer and uploading code to it. Next to the cable is the main control board and the extension board which sit on top of each other on the top of the car. To the right of that is the four tires and four motors, as well as the four brackets that you mount the motors to.

Below that is the infrared controller. To the right of that is the servo that powers the ultrasonic module. The ultrasonic module controller board is just to the right of that, and you can see the “eye” looking thing next to it as well which is the hardware for emitting the ultrasonic waves. Above the “eyes” is the LED control board, and below the infrared controller is the LED strips. The other chips to the left of the eyes is the infrared controller module that you plug into the car to allow it to receive transmitted data from the IR controller. Similarly, the blue chip near the eyes is the bluetooth module that you plug into the car to be able to communicate with your phone, which drives the car as well.

At the bottom is the radio frequency controller parts. The two chips are again for plugging into the car, and the RF remote, which is how you communicate between the two devices. And of course at the bottom right is the chassis of the car.

The first step was installing the motors and tires on to the base of the foundation. That black chip in the front is a line tracking module. It has small sensors that point at the floor that can detect a line. The car can be programmed then to track and follow lines.

Next we installed the LED modules which are the two strips at the front and back of the car. The piece in the middle is the LED control board, which we will soon connect to the main control board of the car.

Below is the main control board, and you can see it is wired to underneath the chassis, which is where the LED control board is. The two LED strips are also connected by wires to the LED control board so they all communicate.

Next we installed the battery pack and a servo for the ultrasonic module. More on that later.

After the Servo was installed (blue piece at top of picture above), we attached the ultrasonic module to it. The ultrasonic module is the piece that looks like eyes of the car which you will see from the completed project below.

Below is a picture of the completed unit with the radio frequency controller.

There are three options to drive the car. The radio frequency controller as shown above. An infrared controller, and a bluetooth module that you can control the car with your phone.

Beyond just driving the car with the controllers, there are other options you can program the car to do as well. There is an obstacle avoidance mode for example that we programmed in. This makes the car drive automatically, but it detects obstacles and moves around them. It uses the “eyes” at the front of the car, which can pivot and look around. Those “eyes’ emit ultrasonic waves which reflect back on the car to help it understand how far away the obstacle is.

Below is the flow chart that you can program in to the car that it uses to determine how the car will move as it encounters obstacles.

Luckily the instructions provide the code for you, as I would have no idea how to write this code myself.

Here is a video of the car after being programmed with obstacle avoidance. In this video, the car is driving itself, and is not controlled by one of us.

I’m sure the components are fairly cheap to manufacture, but the car cost about $90 which felt like a good deal. The batteries however were $17 each, plus a $20 charger, so that was less of a good deal. But overall I enjoyed the product and felt like it was a good learning experience and worth the time and money.