ARDUINO | WINTER 2013
TEAM MEMBERS : Keerthana Reddy , Sonali Sinha
Devising a mechanisms to steer a steering wheel using the circular motion of the joystick.
In Winter 2013, I had taken up Embedded System Design as a subject in my Bachelors. It was then that I realized the true potential of automation. Though the complete prospect of automation excited for a long time, it was during this time , I understood how it works and how it can be deployed at various stages. At this stage, I was inspired to take up this as a project. I wanted to devise a system , wherein a user needs to apply just a minimal force to move the steering wheel of a car.
The application of a minimal force was the most important prospect of this project as it enabled people with various disabilities to continue using their choice of transportation.
The project was developed on the Arduino Uno development board and also utilized a joystick and a servo motor. The basic goal was to map the joystick rotation to the motor rotation which was meant to be attached to the steering wheel shaft.
JOYSTICK (USER END)
The user interacts with the joystick , and moves the joystick in a circular fashion.The joystick is an input device consisting of a stick that pivots on a base and reports its angle or direction to the device it is controlling. It is generally configured so that moving the stick left or right signals movement along the X axis, and moving it forward (up) or back (down) signals movement along the Y axis.
There are basically two analog outputs of the joystick, A0 and A1. They correspond to the X and Y position of the joystick at that time. These vary over a range of 0 to 1023 normalised data. The circular motion of a joystick (corresponding to certain X and Y positions) is mapped to the circular motion of the motor which is 0 to 359 degrees rotation.The mapping is generated by the deducing the angle (A) that the current position of joystick makes with the center of the joystick, as depicted in the sketch above.
Arduino UNO is the core of this complete system. All the data processing and control is taken care of here. The analog data generated from the joystick is put in at the analog inputs of the Arduino . These are then processed (deduction of the angle ) via the code stored in the arduino and then a control signal is generated for the motion of the servo motor.
SERVO MOTOR ( Steering Wheel Shaft)
A servomotor is a rotary actuator that allows for precise control of angular position. It consists of a motor coupled to a sensor for position feedback, through a reduction gearbox. The input to its control is some signal, either analogue or digital, representing the position commanded for the output shaft.
In this project , the servomotor receives the control signal from the Arduino. The servomotor has three connecting wires orange, red and brown .The orange wire is connected to the control brown wire is connected to ground and the red wire is connected to the 5V supply on the arduino board.
The servo motor is meant to be attached to the steering wheel shaft of the four wheeler.