This is a project where I retrofit an old ActiveMedia Pioneer robot with my own custom hardware and software.
The previous architecture for this Pioneer had Windows 98, vision, sonar, encoders, gripper, and a wireless image transmission to a remote screen. Windows 98 and other old equipment had to go before I would work with it. So I gutted out the old parts of the machine.
Using the Pioneer chassis, motors, and encoders, I have installed a new AVR-based microcontroller (MCU), and sonar, and I’m starting to write code that drives the robot while avoiding obstacles.
During the second phase of the project, I would like to incorporate the existing motor encoders as well as a simple digital compass with the MCU.
During phase 3, I’d like to get more into the high level vision such as for this cones race http://www.robotronics.org/competitions.html. And then work on path planning and localization algorithms for this more advanced race http://www.robotronics.org/competitionadv.html. Towards that end, I would add GPS, 802.11g wireless communications for offboard vision, and of course some sophisticated mapping and localization algorithm using path planning algorithms.
Once phase 2, 3 is completed and tested, I will write a technical report. The complete modified platform will be returned to the High School teacher who loaned me out this platform.
It will also be used as a platform to teach his students robotics.
they pr…
What are you thinking about for the high level path planning?
The only thing I remember from school is Voronoi diagrams , where you draw a line around each obstacle that’s offset from its edge. Then draw another outline around the previous one. If you keep drawing outlines, eventually the outlines from one object will hit another object, and if you trace that intersection that path is the farthest away from everything. I don’t know if there’s any way to get it to work in unknown situations. Well anyway, just curious what your high level plans were!
Thanks Scott for reminding me about Voronoi diagrams. I was thinking of VSLAM (visual simultaneous localization and mapping) where you build a map following along the sidewalk and distinguish grass, gps coordinates to a goal destination using Dykstra algorithm to find the best route. This would be for the more advanced competition next year http://www.robotronics.org/competitionadv.html
cool competition… street crossing and everything!
Would it be a bad idea to have one drive belt for each motor. There are 4 motors on a ground vehicle.
These are the motors with sprocket already attached —> http://www.monsterscooterparts.com/24v20mowisp.html
The wheels also have sprockets attached. The wheel sprockets has approx. around 4 inches in circumference and has around 5 teeth per inch.
Those motors sprockets and the wheel sprockets need a compatible belt.
My guess is around 8 inches in total circumference length that also has 15 mm/.59 inches width and about 5 teeth per inch.
I was wondering if this belt would work? I can’t read the specs real well.
https://sdp-si.com/eStore/PartDetail.asp?Opener=Group&PartID=2891&GroupID=213
If someone can help me read the specs to figure out if they would work with my motor sprockets and my wheel sprockets.
I just think one belt per motor would work out best with the chassis size limitations.
The motors look small on the website, but when I got them in the mail they were much bigger than I estimated. So now I need one motor and one belt. Like four wheel drive.
If you can find a sprocket manufacturer’s website, or even mcmaster,
they provide some guidance on how to choose belts.
http://www.mcmaster.com/#drive-belts/=246vqd
You need to match the pitch and type (timing belt “series”), make sure it can handle enough
torque, get the overall length by the geometry of your bot (making
either the motor mount or wheel axis adjustable is a good idea).
I’d make sure to find the actual pitch, getting it “about” 5 teeth /
inch sounds risky. One could be metric and slightly off or something.
(complete instructions)