Whilst we were in the development stages for the project, to alleviate the burden of our time constraints a little, Sam plunged into the construction of the robot. The design was fairly simple, the base model was similar to the initial tribot bar the back wheel (we replaced that with sledges to create more interesting textures on the paint surface. To house the vivid that would mark the roof, the frame was heightened slightly which caused problems -the robot was very top heavy and prone to toppling at very little provocation. He ran on two wheels, to counter the stability issue we resorted to the original third wheel design (just like the tribot) Once he was operational we added the ultra-sonic sensor to navigate the area. Once he reached a certain distance from a wall he would perform a randomly generated turn and continue forward. Also to add patterns to the artwork, we incorporated an arm extension with a sponge attached at its rear. This ran on the third available motor, and was linked to a sound sensor. When this was triggered (by noises over a certain decibel reading such as claps or shouts) the arm would slap the ground; causing a paint 'splodge'. tweaks were made constantly throughout the process. But the main design remained the same throughout.
Doing some research, after Bunnings.
We attached our drips at the back of the robot initially but this made the robot too unstable. The weight was shifted predominantly towards the rear and therefore frequently tipped the robot over backwards, they were later moved to either side, with thin sugical tubing leading under the robot, leaking paint underneath the chassis and in the path of the sponge. We later decided to also soak the sponge in paint before runs to maximise the amount of paint and the diversity of colours going on the canvas.
The programming proved the trickiest part and was handled mainly by Marty. It was completely re-done several times and caused much stress midweek. The main issue was getting the robot to accurately react to the sensors. Once we did finally come up with viable programming solutions for this, the problem then shifted to looping the code in such a way that after a sensor had been triggered, and a reaction undergone, the robot would carry on moving forward again. Jason fixed the problem with a tricky little coding loophole, which I'd like to think I understood and helped come up with in the slightest sense of the word. I found it very difficult, and fully admit that I was not a major contributor to the coding aspect of the project, but I definitely have a better grasp now than at the start of the week.
With the construction of the box I was in more comfortable territory. A trip to Bunnings proved fiscally rewarding (We got a sweet discount). We walked away with MDF panels for the base and roof, EZIply walls and smaller planks to both brace the free-standing walls and to lock the base and roof pieces onto the frame.
Photo demonstrating the method in which the top and bottom panel is to fix to the frame. Four corner 'V' wedges fit tight to the frame itself then attached to the flat panels.
*I'm thinking the easiest way to demonstrate the dynamics of the box design will be with sketches which I'll add once I get access to the scanner.
Another photo showing the frame assembled. Corners braced with bar of wood. All wood adjoined with adhesive then screwed together.
Very functional and altogether not very interesting post this really isn't it. Might leave it at that for now. >Sketches soon