So after some testing moving the platform, we concluded that the wheels are too big for our platform. We weren’t able to move the platform quite easily and turning was a nightmare, so we went searching for a new set of wheels and that resulted in these wheels( see picture below).
These so called ‘ Breaking and locking casters’ are ideal for our platform, because of numerous points. First they are much smaller in size, hence the platform is much easier to guide. Second these wheels can be locked, not only the backward and forward movement but also the rotational movement. At last these wheels look much cooler on the platform :).
For the platform design, we first take stable into consideration. The platform include two parts, the shell frame and wheels. With the help of omnidirectional wheel with lifting device, we can at first put the platform into the ground in order to make sure the stable of device when robotic arm is painting. Meanwhile, if we want to move the platform, we just need to rotate the lifting device and the platform will rise up and can easily moved.
This week we started to assemble the platform.the idea behind the design of the platform was to place everything on the platform, so the robot arm and the control box of the robot arm. We designed the platform with the height adjustable wheels. Because when the robot began to draw, the platform would be lowered to the ground to minimize the vibrations caused from the robot arm and to maximize the stability. After some handwork we finally managed to assemble the platform, the next step was to test if the platform would turn 180 degrees, and there was our first problem. The problem was while turning the platform, there was not enough space between the platform and the wheels, so that resulted in, that the wheels collided with the platform, so the wheels couldn’t make a 360 degrees turn.
We wanted to keep it simple, so our solution was to add two horizontal beams to the front of the platform and assemble the two front wheels on the ’new beams’, in this way we were able to extend the distance between the platform and the wheels to avoid a collision.