Our first Workshop on Line Tracking Robots, Wall E, held on the 4th and 5th of December 2008, was fairly successful, with most robots working and following a white line on the black surface with ease. Most students present were first years, so this should prove to be a great start for them. As promised, I have attached the .C files related to line tracking and other functions of the Robot alongside.
C Programs :
ICC AVR 7 for Windows
Some of the problems you were facing on Day 1 because of bitwise AND & bitwise OR operations were fixed by replacing a file called macros.h.
1. Install ICC 7 AVR.
2. Open the folder containing the file, most probably C:/ ICC 7 AVR
3. Open C:/ ICC 7 AVR / include /
4. Paste this file macros.h in the folder.
5. Windows will ask you if you want to replace the existing file, select yes.
This will allow you to use the functions 'bit_is_clear', bit_is_set, cbi, sbi in ICC AVR, and not resort to usage of bitwise mathematics. Bitwise mathematics however is still valid and can be used if you are more comfortable with it.
Equally good alternatives to ICC AVR are WinAVR and CV AVR.
Presentations shown during seminar (click on View published presentation in a new window when each presentation opens)
Assembly of Robot
Machine Building 1
Machine Building 2
Machine Building 3
Presentation on Atmega Board
Presentation on Introduction to Programming (Blink)
Instructions on Coding in ICCAVR
Presentation on Line Sensors
Presentation on Programming to run your motors and PWM and Line Following
Some points to consider in improvement of your robots for competitions: (Each of these tips will enable you to build something a lot faster and better than your current robot which every person already has)
1. Make a better chassis and better position of the sensors and castor wheel.
2. Use faster motors (will need better control)
3. Use ADC instead of comparators to interpret exact position of sensors (google 'PID line follower' to get a good idea)
4. Use a bigger sensor array with 5 or 7 sensors , instead of 3 (Can be bought from Nex Robotics or made on your own) With 5 to 7 sensors, your algorithm changes significantly, since you'll have to consider all of these inputs while deciding which direction to move in.
5. Designing your own Micro-controller board which will give you more flexibility in making.
The line follower you made was very basic and didn't use most of the otherwise powerful controller (Atmega) features. Google to find better ideas on how to do basic line following and try to implement them on your robot.
Some links and tutorials to help you along (Not Exhaustive):
Robotix (IIT KGP Technical Robotix Society) (Look under general robotics tutorials)
Where to Buy things at Lamington Road:
Our Review with prices
Robotics India's Review
SRA Members who can be contacted for further help:
Praveen Nair : praveen [at] vjti [dot] info
Raj Rambhia : rajrambhia [at] vjti [dot] info
Sisil Mehta: sisil [at] vjti [dot] info
Raghav Ohri: raghav [at] vjti [dot] info