How To Build a Remote Controlled Robot From Scratch

The nice part when I build things in robotics is that I can reuse the components from one project to another. Several boxes full of sensors, motor drivers, and a wide range of kits. What is missing here is just an idea and some time to put it together. So, I decided to build something new, something that I have never built before.

I chose to use a remote control with a receiver, a mobile platform, and one of the powerful motor drivers on the market, and at the same time, the best of my collection. The result is a remote controlled robot.

Such a project requires basic knowledge in electronics (something about voltage, ampere, how to use power wires, soldering, etc.). Moreover, this is a simple project that can be finished in a few hours.

Probably the best books to start building robots:

• Electronics from the Ground Up

• Robot Builder’s Bonanza

• Programming Arduino: Getting Started with Sketches

In this article, I described the components used, how to assemble the components, and finally, you’ll see how I tested the robot in my own kitchen.

The hardware components used in the project

• The remote control is a Flysky FS-T6-RB6 2.4GHz FS: I found the 2.4GHz remote control and the receiver at a good price on eBay, somewhere early this year.

• The receiver with six radio channels: it came bundled with the remote control.

• The aluminum chassis: I bought the chassis two years ago to use it outside (in the park, on the street, etc.). So far, I didn’t play with it very long and not outside the home. The reasons are the following: poor performance of the DC motors, wheels of a breakable rigid plastic, relatively small space inside the chassis, so a greater exposure of the components that are mounted outside of the platform.

• The Sabertooth 2x25A motor driver: I got it last year and is a powerful motor driver capable of controlling high torque DC motors. The DC motors used in this chassis are low power consumption as well as performance.

• LiPo battery: the battery is a 7.4V Zippy with two cells and a discharge rate of 20C.

• Power wires and tools: I needed some power wires, a screwdriver, and a soldering iron.

How to assemble the electronics

This is perhaps the most important part of this tutorial. Here I give a description of the connections between the 6-channel receiver, the motor driver, and battery.

As shown in the previous image, only two of the six channels of the receiver are used.

One of it is connected to the input channel S2, and channel 2 is connected to the S1 input of the motor driver. The receiver is powered by the motor driver, namely the outputs 5V and 0V.

The M1 outputs are connected to two DC motors while the M2 outputs are connected to the other two motors. The positive battery terminal is connected to the positive terminal (+) of the motor driver, while the negative terminal of the battery is connected to the negative terminal of the motor driver.

Huh, I finally finished making the connections. Everything is as I described above.

But there are some details that I need to mention. These include the motor driver which has a number of switches used to set the operating mode and a special switch for the LiPo battery type.

How do I set up the Sabertooth motor driver

Any of the Sabertooth drivers come with a set of six switches. Depending on its use, with a remote control or a microcontroller, the user must change the switches in the correct position. The switch 3 is for the battery and is OFF. When are used LiPo battery, the motor driver takes care and protects the battery to resist at a higher number of charging and discharging cycles.

The switches 2, 4 and 6 are ON

• Switch 2 set to ON – the input signal is analog.

• Switch 4 set to ON – is for the remote control mode.

• Switch 6 set to ON – if the remote control signal is interrupted, the motor driver stops the DC motors as a safety measure.

The Sabertooth driver is connected to the receiver and interprets each received signal from the remote control. This change the direction of the motors depending on the received signal, in other words, I can control the robot to move in any direction I want.

Testing the robot