Time to write an update about the RNet Wireless Stack. The stack has been successfully used for the Sumo Robots as wireless controller. In the last week, there has been a lot smaller and larger extensions for it. And because the nRF24L01+ modules are so inexpensive, I bunkered more than 50, with 20 still left to be deployed:
nRF24L01+ Transceiver Modules
It was Friday the 13th, and it was Sumo Battle Day :-). After 3 months of tinkering, hacking and creatively improving the Mini Sumo Bots, finally the the course tournament took place.
With using a different room, every team had a chance to warm up and recalibrate the sensors for the new environment.
Getting ready for the battles
The time was used to apply last-minute changes and improvements too, plus to record the last Robo Portraits.
If you are familiar with battle games, then typically there is portrait of the machinery you can use. Or if you have every watched ‘competitive’ sports, then every player can have an opportunity to present himself to the audience. So here we go…
Fredy the Commander
Tomorrow will the STD (Sumo Tournament Day)! Here are a few last tips and tricks to be prepared for that Sumo Tournament using the Pololu Zumo Robot chassis:
If two robots crash into each other, there can be quite some force. What I have observed is that it can be strong enough to temporarily disconnects the batteries from their spring contacts. I use pieces of plastic parts to keep the batteries tight and in place.
Battery Enforcement
I have one rule I try to follow every day: my code shall be warning free. Writing software for multiple compilers gets challenging with this rule, but it avoids the ‘not seeing the forest because of the trees’ problem. This rule extends to writing Processor Expert components with CDE (Component Development Environment). What I have missed (and not used) is a useful option to enable debug output:
Enable Processor Expert Components Debug Verbose Mode
The good thing with the internet is: it allows engineers to collaborate. And here is an example: Marc is a reader of this blog had a problem with the I2C hardware of a Freescale Kinetis ARM microcontroller. In his case, the I2C bus could be stuck, and there seems no way to reset it with the I2C hardware on the microcontroller. So a solution would be to reset it with software instead.
Bit Banging Software I2C Driver
There is one week left until all the Sumo robots of the Infotronic course at the Lucerne University of Applied Sciences and Arts will enter a tournament. The robots have to pass a simple tests before they can enter the tournament: to push a ‘dummy’ robot outside the ring. This simple test is used at tournaments to avoid ‘passive’ robots just sitting in the middle of the ring ;-).
Sumo Robot against Dummy Bot
The semester is approaching its end, and students are making great progress: with added infrared and ultrasonic sensors, the robots are able to detect the other robot (more or less 😉 ). Additionally the RNet stack adds extra remote control capabilities.
Zumo Sumo Battle
Things are very much in the testing phase, and some robot (or operator?) failures are really funny 🙂 For sure much more advanced moves compared to previous week. Including extra benefits like a robot bringing a bottle of water! The following video hopefully gives an impression:
Happy Roboting 🙂
For my RNet stack I need a way to identify nodes in the network using a unique address. What I need is Media-Access (MAC) address. Base on such a unique address I can assign short addresses (e.g. with a DHCP or similar protocol to automatically assign shorter network addresses). So how to uniquely identify my network nodes?
The Freescale Kinetis microcontroller have nice feature: they have a Unique Identification Register (UID) which would be a perfect fit for a MAC address :-).
UID Output
Usually, there are two flavors of Sumo robot competition:
Just for fun, I have implemented a wireless remote controller application for my Zumo Robot using the Freescale SRB (MC13123) board. I’m using the Freescale MMA7260Q accelerometer on the SRB board to control the robot.
Accelerometer Remote Controller
MCU on Eclipse 