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lastRites
08-09-2010, 07:57 PM
I want to make fast Line following bot. :) But I know nothing about microcontrollers or development boards :p. I know programming in java and c++ and have some experience in making manual battle bots but I am keen on starting with autonomous robotics. I have looked around this site but I still do not have a clear idea about the basics. Can you guys please list the components that I will need and if possible a rough guide about how I should get about building the bot.:D Thanks:)

Edit:
Things that I already have:
4 R.C. cars
1 IR controlled Helicopter
6 12v dc 200 rpm motor
4 12v dc 100 rpm motor
2 battle bot chassis
1 car wiper motor

pratheek
08-09-2010, 08:22 PM
First, decide on the mechanical design of your robot.

Then decide on the sensors you will be using to sense the line - LDRs, IR sensors, etc. LDRs are slow so you will have to go with IR sensors.

200 rpm DC motors will be more than enough for a decently fast line follower, when used with wheels of 6 - 8 cm diameter.

For the power supply, you can choose between Ni-Mh, Li-ion and Li-Poly batteries. Li-ion is light and powerful but expensive. Ni-Mh is cheap and easily available.

Algorithm is what you will have to spend more time on. You can use the standard left-right algorithm. You will get the best results with a PID control though.

I have just given the options available to you in brief. For a more detailed explanation, google search or post here.

akshay66
08-09-2010, 09:33 PM
Hi all,
I really like the way you had put your problem.Although, pratheek has given you a rough idea.

For motors first use 100rpm and then when you perfect your code go for 200rpm as you have both the options.
For sensors go for an IR led and Photo diode pair.You have to put an ir led and photodiode on a small piece of wood or maybe plastic at a distance of 2.5 cms. Make 3 such sensors.Mount them in front of your bot.I hope you know how to use these sensors.

If you don't know anything about microcontrollers then take some time learning about them and how to program them.there are various options to choose from starting from x51 to AVR to PIC.Read other articles about LFRs and get some experience .

use normal 12v 3000mah -4500mah batteries in lithium Ion they'll cost you between 350 - 650.Good ones maybe costlier.

Search for microcontroller less line follower robot on google.They are simple and easy to build but you won't be able to learn much.

lastRites
08-10-2010, 07:13 PM
Thanks guys for the prompt reply!!
@ pratheek : I will use IRs then but I also have to factor in the cost of the bot. A step by step explanation or a link to one will be highly appreciated ;)
@ akshay66 : I dont know anything :P Can you suggest a good beginner's micro controller and prototyping / development board. (Are parallax boards available in kolkata ?) Please suggest the ones that can be reused and is versatile enough to be used for my future projects.

lolman_returns
08-10-2010, 08:51 PM
@lastRites: Try Arduino. You will never turn back. Another board worth mentioning with lots of support is XBoard by extreme electronics.

akshay66
08-10-2010, 09:16 PM
I'd suggest arduino too.......

akshay66
08-10-2010, 09:22 PM
http://robotechno.us/line-follower-robot-tutorial.html
Best link for beginners.......
look at the way he has used his sensors you can modify the positioning in your bot.IR are cost effective 3 sensors would cost you 90 and the discrete components for 100 so the sensor module can easily be build under 250( higher side ).

He has used AT89C2051 as his microcontroller.Its a 20 pin 8 bit microcontroller.Its good for a simple application like this but you can't use it for high end appications as you will make some in future i assume so keep it aside and go for arduino boards.They are one time invesments for about 1500 - 2000.

lastRites
08-11-2010, 09:49 AM
Thanks for your suggestions :) I have decided to go with an arduino board. Once I am comfortable with the line followers I am keen to move on to sumo bots. So I think I should purchase an arduino board with an atmega32 :confused:. A list of the parts that I think I will need to make this bot:
A microprocessor - atmega32
An arduino development board - ??
A motor controller - ??
A 12V lithium ion bat pack
2 motors - 12v 100rpm dc
A line sensor module - 4 IR pairs mounted on plastic
A chassis - plastic/metal
A breadboard
An avr usb programmer for atmega32 - ?? (Do I need this or is it built onto the arduino board??)

Am I missing anything?? :p
I want to buy the development board but I'd like to make the sensor array :D .

pratheek
08-11-2010, 10:16 AM
Most Arduinos and its clones, come with an Atmega8, Atmega168 or a Atmega328. Any of these should be sufficient for a line follower.
You will need no additional programmer to program the Arduino.

The Arduino cannot control DC motors directly. You will need a motor shield.

If you had tried to read a little more about the Arduino, you would come to know this yourself.
Before planning to buy anything, do collect as much information as possible about the product.

lolman_returns
08-11-2010, 12:25 PM
Thanks for your suggestions :) I have decided to go with an arduino board. Once I am comfortable with the line followers I am keen to move on to sumo bots. So I think I should purchase an arduino board with an atmega32 :confused:. A list of the parts that I think I will need to make this bot:
A microprocessor - atmega32
An arduino development board - ??
A motor controller - ??
A 12V lithium ion bat pack
2 motors - 12v 100rpm dc
A line sensor module - 4 IR pairs mounted on plastic
A chassis - plastic/metal
A breadboard
An avr usb programmer for atmega32 - ?? (Do I need this or is it built onto the arduino board??)

Am I missing anything?? :p
I want to buy the development board but I'd like to make the sensor array :D .

/facepalm..... I thought you would atleast do a google search and find out what an arduino is.... Wow.

lastRites
08-11-2010, 10:02 PM
Yes I have googled it! "An Arduino is a single-board microcontroller and a software suite for programming it" But anyone who has read my posts should know that I dont know a thing about microprocessors :) Thanks for your helpful suggestions. Should I go for a Duemilanove or a Mega board?

rao
08-11-2010, 11:06 PM
Go for Duemilanove (328).. Look for a decent motor driver shield with the arduino that can take atleast 2A per channel and you are good to go.

lastRites
08-12-2010, 06:22 PM
Thanks rao :) Would it be better for me to get the parts online or from a shop? I am from kolkata btw.

rao
08-12-2010, 08:43 PM
I am not sure of the shop scenario in Kolkata, I would suggest you to look at online stores first and compare the prices with the shops at your place.

If you know of a store in Kolkata that sells electronics parts and arduinos and other dev boards, dont forget to put the store address here so that other people from Kolkata
may benefit from the information.

lastRites
08-13-2010, 11:26 PM
Sure. There's a shop called Gemini Radio in chadni chowk market that sells robotics ware but I dunno if they stock arduino products..

Coolpratheesh
08-14-2010, 12:29 AM
try simplelabs and Rhydolabs..... dey r the official suppliers in India for Arduno...

akshay66
08-14-2010, 12:53 PM
No they don't stock arduino.

http://www.rhydolabz.com/index.php?main_page=index&cPath=123&zenid=38d148ee4c8375b0fe4c5959790d1b38

http://www.simplelabs.co.in/drupal/products/products-dev

http://www.bhasha.co.cc/category.php?id_category=10

http://feemo.in/

lastRites
06-26-2011, 01:16 AM
I got my Arduino Uno last week. Thanks for all you help.

thinkanish
09-09-2011, 09:05 PM
Hi,
You can even consider this:
The link given by akshay66 is perfect for a beginner.
You can replace the atmega microcontroller with the PIC16F84A which is a very easy to use and understand controller.
All you need is->
1. PIC16F84A (of course with crystal oscillator - 4 to 20MHz)
2. This very simple micro JDM programmer (http://www.semis.demon.co.uk/uJDM/uJDMmain.htm) for PIC16x8x controller
3. L293D motor driver
4. LM358N opamps for the sensors
5. IR sensors (photodiode, IRled pair)
6. Two 12v DC geared motors(200/100 rpm)
7. 7805 voltage regulator for powering the PIC and opamp circuits.
8. 12v dc power (any battery of choice - connect motor driver with 12v to drive motors)
9. Omniwheel (optional)

Softwares: Microchip MPASM(to compile asm code)/ PIC c lite (to compile C code)
and datasheets of the respective ICs
Now, you know what to do with these.


Regards