The Return

We were hoping for a nice, easy, gentle return to our robot after New Year. Unfortunately, that was not to be.

At the end of the last term, we had just sent away for some new parts - a second battery pack (for safety purposes), a converter for the power pack so it can actually supply power to the robot and also three line sensors. The issue currently is that these have not yet arrived, making testing rather hard as none of our Pi, our Arduino or our motors can actually do anything.

Another problem is that our robot is 2.5cm too wide - we carefully made sure the chassis was within the width when we bought it, either assuming that the chassis width given included the wheels as they were bought together or forgetting that we needed wheels on both sides of the robot as well. This has led to ongoing discussions about how manoeuvrable our robot is and whether or not we are comfortable that we can still do the challenges, as we are still well below the max diagonal. The key challenge will be any thin parts of the obstacle course, but the advantage of our snazzy wheels is that we could move the robot sideways, as our robot is currently wider than it is long.

We also found out that compressed gas of any sort is banned due to explosion risks, so our nice plans for actuators and solenoid valves for the nerf gun have yet again been proved impossible (now I see why extra points are on offer for coming up with your own firing system). Our current alternative idea is an MDF strip to function as a lever and a small servo for lifting the gun with another servo to pull the trigger.

In slightly better news, we have a functioning colour recognition system using our PixyCam now - blue and green are all sorted, the PixyCam seems to like yellow and we are working on the red recognition (why it can differentiate blue and green but not red I am not quite sure, but that’s why I blog and organise people instead of coding colour recognition). This is an important component for our robot, as in addition to being primarily for eco-disaster, it could be really helpful for minesweeper (locating coloured squares) and escape route (the blind maze).

The other key moment in today’s meeting - only for me but I was excited nevertheless - was being taken to the electronics lab. As I only joined the school in September, I’m still enjoying discovering new rooms. After learning to solder at my work experience placement over the summer, I am really excited to get back to sticking bits of metal together, although there is slightly more pressure now that I’m soldering together a robot rather than a very basic circuit consisting of only an LED, battery and a variable resistor. The soldering is going to be necessary for some wiring bits and bobs to get all the wires connected to the relevant boards. When the last few parts arrive hopefully we can get out the soldering iron to get everything working nicely.

By Laura Hollister

Written on January 8, 2020