Line Following Ti 84 Calculator Robot

This guide explains how to program a line-following robot using the TI-84 calculator as its brain. Line-following robots are simple but effective for learning basic robotics principles. We'll cover the necessary components, programming steps, and testing procedures.

Introduction

Line-following robots are a great way to learn about robotics and programming. By following a line on the ground, the robot can navigate a path without complex sensors or algorithms. The TI-84 calculator can serve as the robot's brain, processing sensor inputs and controlling motors.

This guide assumes you have basic knowledge of electronics and programming. You'll need a TI-84 calculator, a breadboard, and some basic electronic components to build the robot.

Robot Components

Hardware Requirements

TI-84 calculator
Breadboard
Jumper wires
Motor driver (L293D or similar)
DC motors (2)
Infrared (IR) sensors (2)
Power supply (9V battery or adapter)
Chassis and wheels

Circuit Setup

The circuit connects the TI-84 to the motor driver and IR sensors. The motor driver controls the DC motors, while the IR sensors detect the line. The TI-84 reads the sensor values and sends signals to the motor driver to adjust the robot's movement.

Note: The TI-84's I/O pins are limited. You may need to use a TI-84 Plus or TI-84 CE for more advanced projects.

Programming the TI-84

The TI-84 program reads the IR sensors and controls the motors based on the sensor values. Here's a basic program outline:

Program Logic:

Initialize motors and sensors
Read sensor values continuously
Adjust motor speeds based on sensor readings
Repeat until stopped

Example Program

Here's a simple program in TI-Basic:

:Input "Enter threshold:",T
:While not(getKey)
:If sensor(1) > T and sensor(2) > T
:motor(1,50)
:motor(2,50)
:ElseIf sensor(1) > T
:motor(1,30)
:motor(2,70)
:ElseIf sensor(2) > T
:motor(1,70)
:motor(2,30)
:Else
:motor(1,0)
:motor(2,0)
:End
:End

The program reads the IR sensors and adjusts the motor speeds based on the sensor values. The threshold value (T) determines when the robot should turn.

Testing the Robot

After programming the TI-84, test the robot on a simple track. Start with a straight line to verify basic movement, then try curves and turns to test the robot's ability to follow the line.

Adjust the threshold value and motor speeds as needed to improve performance. Record the results and make notes for future improvements.

Troubleshooting

If the robot doesn't follow the line properly, check these common issues:

Loose connections between components
Incorrect threshold value for the IR sensors
Motor driver not receiving power
Program errors in the TI-84 code

Refer to the TI-84 manual and motor driver datasheet for additional troubleshooting tips.

Frequently Asked Questions

Can I use a different calculator for this project?: Yes, but the TI-84 is recommended due to its I/O capabilities. Other calculators may require additional hardware.
How do I adjust the robot's sensitivity?: Change the threshold value in the program. Higher values make the robot more sensitive to line detection.
Can I add more sensors to the robot?: Yes, but you'll need to modify the program to handle additional inputs and adjust the logic accordingly.
What's the best surface for testing the robot?: A light-colored surface with a dark line works best for IR sensors. Avoid reflective surfaces that may interfere with sensor readings.