nye

I have been in electronics for about 2 years. i thought of building a robot.could somebody tell me the requirements to start in robotics??? by the way, i live in Sri Lanka(haven't heard of it right) so i don't know as to whether some components can be bought here.anyway tell me the reqs. i mite be able to get it from friends. also inform me of any computer hardware or software required
Thanx

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\"electricity is a good slave, but a bad master\"

ivancho

I have a word for you......."microcontrollers"... it all starts there.... then depending on what you want to do comes the sensors. H-bridge, Motors, servos, and steppers are clue words as well.....

Mechanical wise you must be able to make bases out of whatever light material you have available like aluminum, Extrudede PVC sheets, flexiglass, etc. Attach wheels to a motor and belts. I would suggest starting a project, and work from there... how about a wall following robots :idea:

Ivancho

falleafd

Yeah, microcontroller is the first thing you need to understand. But I think wall following is a difficult problem. You should try with line following.

For wall following, you have to solve a Lyapunov controller, or using observer. It's quite difficult for beginners. However, with line following, there are a way to use PID controller and they found it stable if your sensor is put in front the robot. You don't have to resolve it again

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bmcculla

Wall following is actually really easy. All you need is a switch that hits the wall. When the switch is activated the robot backs up and turns a little then move forward untill it hits the wall again. I had a lab in college that we made analog robots that did this. They have since started to use microcontrollers in that lab.

Brent

falleafd

Yeah, if you intend to do it as easy as right and left series controling. However, the line following was proved that it is stable if you put the sensor in front the robot. But the wall followers are not yet popularly proved. And do you know how many touch sensors should be used? and where it should be put? I know that if you don't care of these, you may build a simple one. The fact that, in this case, both line follower or wall follower is the same.

http://www.falcks.com/arturo/portfolio/Frame.html

Pls take a look to this page and role down the frame, you will see the line follower was solved clearly.

But to wall follower, I know a project using 2 mechanical sensors like this, but it's quite difficult. It's not as easy as line follower.

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para_cavern

i have a severe hatred of microcontrolers. I much prefer using logic ic's to help in making projects.
the following are very good to have if you are interested in robotics;
motors with gears - very useful, particularly ones with worm drives.
lots of electronic components - get some old broken electrical appliances and remove the components from them = very useful.
switches and sensors - the core of robotics.
shall send you some more info later on. dont worry about being in shri lanka - companies mail order so it doesn't matter where you live. :idea: [/img]

marchache

I too am just getting started and came across an outstanding reference text. Not sure if you can find it in Sri Lanka but www.abebooks.com has a bunch available. Check with them to see if they can ship it.

It's called "The Robot Builder's Bonanza" by Gordon McComb.

I like it becuase it takes a very building block approach to robot construction. You can start with a basic two x 6vdc motor with DPDT switches to turn them on and scale up to a 6 legged walkerbot using the same principles. It discusses, motors, batteries (including how to build a battery charger), building a power supply, tethered control, remote control, microprocessor control, computer interface, various sensors, grabber arms etc.

He also discusses how to canabilize kids toys (using cheap walkie talkies as a basic remote controller for instance) and where to buy parts for cheap.

Very very good book. Well written and easy to understand.

Marc

falleafd

Thanks muchie, but why I cannot come to this page?

I download 6 chapters of this book, and feel it good for beginners. Thanks for all.

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