Plan vs Reality Part 2 - Building the Courses

The Arena

The original plan was to build a foldable solid arena from wood painted matte black with a white hardwood floor. 

However, the final arena was built from plastic "Foamex" sheets cut to size from an online company: http://cutplasticsheeting.co.uk. This actually worked out a similar price to the wood we would need and it came in matte black, so there was no painting involved. We stuck it together with tape and Velcro to form the arena. 

Rather than build a hardwood floor, we stuck to using the kitchen floor and marked out the challenge courses with tape before filming.

This worked well - although I think it would have been better to build something more solid.  

The arena marked out for the "Up The Garden Path" challenge. 

Tidy The Toys

We bought some 5cm wooden cubes from eBay and covered them in coloured tape. I thought this would be better than paint - but was wrong - the colours were very patchy where the tape stretched or overlapped. However the biggest problem was the weight - they were too heavy for our gripper to pick up consistently without slipping. 

Tape Covered Solid Wooden Cubes.

So we decided to make some from ply wood. These were much lighter and the templates I had printed out for cutting the blocks were the right colour for detecting.

ply-wood cut cubes. 

However - as we were testing in the kitchen, occasionally there would be small drops of water on the floor that caused the ink to run and they soon looked a mess. So we took some thin coloured cardboard sheets and used it to cover the blocks. These looked much better and the solid colours worked well for our colour recognition. 

Cardboard covered cubes with colour detection.

These blocks were the ones we used for the final filming of the challenge.

Feed The Fish

The original blog was very brief over our plans for building the fish bowl. I mentioned that I was looking for any cardboard boxes that were the right size for building it. 

Well, as luck would have it, I received a pizza oven for my Birthday at the end of November and, like a kid who's more excited about the box than the toy inside, I knew the box would be just right for building the fish bowl. The pizza oven was pretty good too - pizzas + robots - is there anything better? 

The plain cardboard fish bowl was used for testing, but before we filmed the challenge we covered it in white paper so the boys could decorate it. They painted sand, water and kelp using watercolour paints and stuck on some real shells. They also drew some Pokemon fish that they stuck on. Because our camera could only see the bottom half of the box, we made a 'no golf balls' sign to go over the bottom opening, and our camera targeted the yellow 'sand' at the bottom of that when aiming. 

 

The Decorated Fish Bowl

Obstacle Course

Back in November last year when I wrote the original blog, we didn't really have any ideas for the obstacle course. 

We have a small lawn in our garden with a path running all the way round, so we thought that would be perfect for setting up the course, but didn't really have any ideas for the obstacles. 

As the months progressed, we came up with a few ideas that fit with the DIY theme and noted them down. 

These included: 

• "Pit of Nails" - a tray of nails and screws that the robot had to drive over.
• "Builder Tea Slalom" - mugs of very strong tea set up as a slalom obstacle. 
• "Wonky Shelves" - a series of pivoting ramps. 
• "Cement Mixer" - the robot has to enter a bucket and drive inside to move over obstacles. 
• "Sledgehammer Pendulum" - the robot has to drive through a swinging hammer. 

The bucket idea didn't really work - the robot couldn't drive in due to the curved sides, and if we did get it in, as soon as it hit any obstacle, the robot would drive up the inside of the bucket and fall upside down. We did keep a homage to this idea in the final run using a flexible plastic garden 'trug'. Because this is flexible the robot was able to drive in, but instead of trying to move it over obstacles, we just used the driving inside technique to get it out of the way of the path. 

For the 'Pit Of Nails' we built a tray with an offset entrance and exit - but instead of just nails and screws we also put in some tools for the robot to drive over. 

The "Terrible Tray of Tools"

The 'Wonky Shelves' idea turned into a 3 part flip ramp with the middle ramp higher than the outer two. This was the biggest thing to build in the obstacle course. 

The "Wonky Shelves"

The other ideas we implemented as planned - and added some off road driving and some paving slabs. 

We had always planned to do this challenge using remote control only our 11 year old could show off his driving skills. 

We realised late on that if we used voice commands, we could gain some extra points, but, with time running out to film the challenge, we kept to remote control only.