COMPLEX Version 2.0 robotThe previous version (found under 'Final robot') had some serious design flaws. Although it worked, it was way too expensive, used way too much space, was way too much work to 'get it up and running', the available space on the PCB's was not optimally used, in one of the PCBs a very serious flaw was introduced (although the design was ok) and was from a programming point of view: crap.
There are a few reasons for this:
- The seperate blocks were distributed over the PCBs in the wrong way.
- This demanded a lot of wide interconnection cables.
- Much space on the PCBs was lost by the connectors and pulling wires from and to these connectors.
- No seperate bus for control and data transfer from and to the datalink.
- Functionality was wrongly distributed over the various microcontrollers.
- This made that serious timing problems occured between the various microcontrollers.
In the new version these problems are addressed by the following considerations:
- Each PCB us a complete 'independant' unit with only a relatively small (10 pins) bus connector.
- The PCBs are powered by bus connector. Only if much power is needed, an additional power connector is added.
- The used bus between the independant units is I2C. This is a synchronous simple protocol.
- Seperate supply for logic and drive.
- One PCB houses all the basic functionality of the cart. (supply, battery management, H-bridges for drive motors, cam tilt, cam light, cam on/off).
- This PCB also acts as a central connection point for all the other devices.
- The main controller is housed on a very small and simple PCB.
- This makes it possible for the contestants to write their own control program, burn into their own main controller, and plug it in.
The datalink board and de usercontroller board may be replaced by a small enough Wireless Router. This has a lot of possibilities. In the first place, its much easier to develop software, since the control hardware is way more powerfull. Next, the datalink is now a piece-of-cake, since this is already by the router itsels.