Society of Robots - Robot Forum

Mechanics and Construction => Mechanics and Construction => Topic started by: KrAfTwErK on December 14, 2010, 11:19:24 PM

Title: Need Help to Build Robot from Junkyard Parts
Post by: KrAfTwErK on December 14, 2010, 11:19:24 PM
I would like to construct my first robot--something that's very basic in scope and function, made entirely from parts that can be gotten from a car junkyard. I go to the junkyard for parts for my cars at least once a week. I am always there pulling my own parts. A customer of mine told me that he needed a cruise control actuator to use for his robot project. THis got me interested in and curious about robots. After much Youtube-ing I decided I want to make my own, but constructed completely of parts that are meant for cars.

Has anyone seen such a robot? If so, post me a link to a thread from someone who has done this, preferably with pictures. The first goal is just to 'make something that does something' and get it completed as soon as possible. If successful maybe I will try for something more.

Title: Re: Need Help to Build Robot from Junkyard Parts
Post by: knossos on December 15, 2010, 05:54:10 AM
You could make an H-bridge to drive your motors from automotive relays.  You can use some of the DC motors from seats and a car battery to drive it.  The biggest things you would be missing for a simple robot that might be difficult to get from a car is sensors and a controller.  You can use switches for tactile sensing, but you would also want something that senses things at range, since any robot dragging around a car battery is going to be fairly heavy.
Title: Re: Need Help to Build Robot from Junkyard Parts
Post by: Soeren on December 16, 2010, 05:30:51 PM
Hi,

MCU's have got motor drivers for...
- The idle adjust stepper and they could be used for H-bridges (but get two of the same MCU, as there might be just 2 of the same kind in a box (the idle stepper is a 6V device, so only uses a half bridge).
- And the injectors are pretty low impedance and must react fast, so their drivers can pull a fair amount of current.

In the ones I have opened, all chips and transistors have been clearly marked - invaluable when looking for datasheets.

Window motors should be good for various stuff too and are fairly easy to get to.
 
Title: Re: Need Help to Build Robot from Junkyard Parts
Post by: T0110100101101101K on December 22, 2010, 09:12:09 PM
Sensors are definitely a tricky one for doing something useful as a robot.  If you use the mentality of the $50 dollar robot tutorial www.societyofrobots.com/step_by_step_robot.shtml (http://www.societyofrobots.com/step_by_step_robot.shtml), you can look for a photoresistor in the cabin light circuit.

Since this is your first robot, you may want to consider many of the points on this site www.arrickrobotics.com/arobot/build.html (http://www.arrickrobotics.com/arobot/build.html).

I think the SoR way to start is a good methodology.  Going to the $50 robot tutorial is probably the best option for keeping it simple and accomplishing #1.  After that, the sky is the limit.

 
Title: Re: Need Help to Build Robot from Junkyard Parts
Post by: koolraj09 on December 27, 2010, 11:22:58 PM
Regarding motors you have choices.
You can use starter motors, wiper motors or automatic window motors etc. Also you can strip batteries from the car. But all this makes things the most heavy.