REMOTE CONTROLLED ROBOT

1.  INTRODUCTION

We have seen many projects where a robot is controlled by a remote controller. Here we describe a robot that can be steered in any direction just like you drive your car. Wireless steering senses the motion and transmits corresponding instruction to control the robot through RF communication. The robot also has an obstacle detection and avoidance system implemented.   

1.1  Circuit and working

Fig shown below is the block diagram of the complete project. The movement of the steering is sensed by the accelerometer. The data from the accelerometer is processed by Arduino Uno board and corresponding instructions transmitted through the RF transmitter to control the robot. The robot receives the in-structions and the MCU section drives motors corresponding to in-structions received. Obstacle detectors sense any object in the way and intimate the mi-crocontroller to stop forward motion.

1.2 Wireless steering

It is built around Arduino Uno board (Board1), encoder HT12E (IC1), regulator 7805 (IC2), 433MHz RF transmit-ter module, accelerometer module and a few discrete components. Pins A0, A1, A2, A3, A4 and A5 of Board1 are connected to pins ST,

Z-axis, Y-axis, X-axis, GND and VCC of the accelerometer module, respectively.

1.3 Accelerometer module

An ac-celerometer is an electromechanical device that measures acceleration of anything that it is mounted on. The accelerometer module used here is based on ADXL335 triple-axis accelerometer from Analog Devices. The sensor has a full sensing range of ±3g.

1.4 Arduino Uno board

Arduino is an Open Source electronics prototyping platform based on flexible, easy-to-use hardware and software. It is intended for artists, designers, hobbyists and

anyone interested in creating interac-tive objects or environments. 

1.5 Robot

It comprises an RF receiver module, decoder HT12D (IC3), microcontroller PIC16F877A (IC4), operational amplifier LM324 (IC5), motor driver L293D (IC6), regulator 7805 (IC7) and a few discrete components.

1.6 Software

The wireless steering is built around Arduino Uno board. Arduino Uno is programmed using Arduino IDE software. ATmega328 on Arduino Uno comes pre-burnt with a boot loader that allows you to upload new code to it without the use of an external hard-ware programmer. It communicates using the original STK500 protocol. You can also bypass the boot loader and program the microcontroller through ICSP (in-circuit serial programming) header, but using boot loader programming is quick and easy. Select Arduino Uno from ‘Tools→Board’ menu (according to the microcontroller on your board) in Arduino IDE and burn the program through standard USB port in the computer. The source program for the robot is written in ‘C’ language and compiled using MPLAB IDE for the robot. Burn the hex code into the microcontroller using a suitable programmer. Program execution starts by initialising the input and output ports. The program checks the received data for forward, backward, left and right movements and gives correspond-ing control signals to the motor driver.

2. LITERATURE SURVEY

We have seen many projects where a robot is controlled by a remote controller. Here we describe a robot that can be steered in any direction just like you drive your car. Wireless steering senses the motion and transmits corresponding instruction to control the robot through RF communication. The robot also has an obstacle detection and avoidance system implemented.

The idea to this project initially was gathered from an article given in Electronics For You magazine February 2013 issue titled “Cars : Packed With Electronics from Boot to Botnet”. The article published on page 113 of the above mentioned magazine was titled “Robocar With Wireless Steering”.

Also the project includes various discrete components which required deep study of some components involved like arduino board, rf module, accelerometer and PIC microcontroller.

The arduino uno is an open-source prototyping platform which has various sources of study involving its official website “www.arduino.cc” and several forums associated with it. Also there are books being written by its founders that are “Beginning Arduino” by Michael McRoberts and “Getting Started With Arduino” by Massimo Benzi.

Detailed information about PIC microcontroller was gathered from its manufactureres’ site that is “ww1.microchip.com” in the form of datasheet.

Accelerometer is a latest device being used in most of the smartphones today. The accelerometer being used in the project is ADXL 335 manufactured by analog devices and its datasheet is also provided by analog devices ,

Various web articles were referenced which are being given in the refrences column at the end of this synopsis.

3 APPLICATIONS

3.1 In Military:

Wireless steering for military tanks and jeeps could serve as a great tool which could save life of military persons as they could be operated from a distance.

3.2 Automated Vehicles:

As one of the most successful applications of wireless steering, driverless vehicles have recently received significant attention, especially during the past several years. At least two reasons account for this trend: the first is the wide range of commercial applications, and the second is the availability of feasible technologies after 30 years of research.

3.3 Security and Monitoring Purposes:

Robocars with cameras can be developed for security and monitoring purposes by security agencies as well as home users.

3.4 In Children’s Toys :

Wireless Steering is easy to operate hence children will find it more easy and useful.