Yes thanks, the link you give is in the right direction..... there are better deals however its always a balance of how "slow the boat" is if you know what i mean.
I have also experimented with many types of homebrew wheels , i always fall back to rubber based compounds (grippy) rather than the plastic ones you see around (ie connected to yellow GM motors).
In the last few days i have found a way to use a simple "lego coupling collet" than slips over the motor shaft enabling any type of lego wheel (technic or normal) to be easily used with perfect alignment. Plus factor is that these wheels are easy to come by. This lego transition part enables the flexibility of adding other standard lego motive parts to the motors (ie cogs and arm followers).
If you search "5V Stepper Motor 28BYJ-48 With Drive Test Module Board ULN2003" on ebay it will throw up a host of suppliers (I paid £0.99 for mine). Just check that the driver board is also included. The speed is as seen in the video second two videos (it is real time) .. If you start pushing up the speed then steps will be missed, however i guess if you are willing to drive them with a higher voltage (mine are 5V) then speed would improve (however at the risk of burning them out ... (the driver board allows splitting of the data and motor supplies). (With 5Volts the current is circa 200mA under load/drive and 220mA in stall condition). Regards Gareth
This project was devised to show how easily it is to make a robot on limited funds. Video of Build process :-
It is a good "Starting Off" Robotic platform as it can be easily changed and transformed.
This is just the start of the project and there are many additions planned for it.
It is a cross platform base, meaning that any micro computing unit (Brain) can be used ie. Arduino Atmega range, Propeller or Picaxe. Due to its low cost i foresee me building a "Swarm" of them .....this one is already the second. The first one is here :-
The base uses Geared Stepper motors which means that it is very precise and repeatable in its movements. ( forget your sloppy continuous servos )