Posts

False Positives and Line Following

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 I've finally got around to laying out the Garden Path challenge and tested it with an unmodified line follower code used (supposed to be used) in Lava Plava. Needless to say, it kinda crashed and burned. It's not quite as bad as I expected but which fork the robot took was more by luck than any programming on our part. I set up a Pi4 and camera pointing at my monitor with a "rolling road" displaying the computers view to determine how best to handle the junctions the robot will come across. The frame rate is nowhere near what we achieve on the robot, as the image is being streamed across SSH. However, for the purposes of recognising the junction patterns, it should be ok. The red border shows the detected line and the blue line shows the heading the robot needs to turn to to get the line back in the centre of view. The red figures indicate motor overall power (g) and, left(l) and right(r) motor power between 0 and 1. Turning right reduces the motor on the right keepi

Happy New Year (and we hope its better than the last)

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Gripper update. The grippers have been sprayed and a non-slip coating has been added. Grippers The software has been modded slightly to maintain continuous pressure on the block, once the grippers close, and a control button to switch off the gripper servo when the grippers are not closed. This seems to work reasonably well but we might require more tweaking as the cubes are quite slippery. Blocks We now have three cubes of different colours for the "Tidy Up The Toys" challenge. Amy has produced some nice menu artwork including this one for "Feed the Fish". Carping On She will also be giving a talk at the PiWars conference about this and her other digital art, see https://piwars.org/2021-vc/ for details.  Feed the Fish Team Forest Fighters still can't decide how to do this challenge either using a catapult or shove halfpenny methods. Having printed a catapult and launching nerf rounds across the lounge never to be seen again behind the TV, we are thinking thi

A quick diversion and a Happy Christmas!!!

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Along with having some colourful, python powered colour changing windows, we wanted some additional festive cheer. So Amy's dad created a small pixel matrix display... ...and its now installed in one of the front windows! The four front windows are surrounded by rgb led strips each controlled by an ESP8266, with a master python program telling them what to display, via WiFi using HTTP commands. Happy Christmas everyone and hopefully 2021 will be better than this one, after all it has the Pi Wars competition in it.

Symbol Recognition

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For the Up The Garden Path challenge, we haven't quite decided if we are going to use voice commands or pattern recognition combined with line-following, (or even a mix of all three! ). Amy's dad has been looking at pattern recognition and converting some C++ code to Python to see if it was quick enough on a Pi4. We have previously used Open CV for line following. Amy's dad used the same process back in 2014 for the first line follower code that Ipswich Makerspace's Tractor Bot used, but that was C++. Back then the Pi wasn't really up to it. This example video was using C++ on a x64 PC.  The next video is from over six years later. In 2020 the Pi4 can match that and do a whole lot better with Python (especially since this is over VNC.) (The cube is a 50mm reject from the 3d printing earlier covered with self-adhesive printed signs). You can find the source for this to experiment with here: https://github.com/ForestFighters/Symbols  

Into the unknown with Voice Commands.

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Amy's dad here with a quick update on PiWars 2021 progress..... We have busy with other projects so its been pretty quiet on the Pi Wars front, however the basic robot software and hardware is essentially going to be the same as last year (2020) but with added voice commands.  I have been checking out Vosk as a way of getting a Pi to understand voice commands. Here is a quick video showing its not too shabby, especially for single word commands. The main advantage of Vosk is that it is local to the machine rather than using the "Cloud" so even if your cloud service provider is down (note Google authentication went down yesterday for a couple of  hours so not impossible!) you can still command your system using voice. Also it doesn't seem to use much processor (considering I recorded the video over VNC!)

New 3D prints...

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Since the barrels of the 2020 competition have changed to cubes, the 3D printer is hard at work creating some new items. Including remaking the grippers so that they grip the cubes better. I will cover inner surface of the gripper faces after painting with some non-slip material.  Yes, I know we only need one of each colour but my green filament had not arrived.  We use Tinkercad for its simplicity and for generating 3D models quickly and accurately it does an excellent job.

Guess Who's Back?

Forest Fighters are happy to announce we will be entering virtual Pi Wars this year~ We will be building off last years robot (Audrey III) and adapting her for any new challenges so expect a full-scale makeover. Keep tuned in for more updates to this year's blog!✨✨✨