Our new wheels and motors arrived. the motors were smaller than our previously used ones and fit partially into the wheels, a big space saver. We decided as our motors were powerful and our wheels had more than adequate grip that we would use a two wheel and ball system.
The ball eliminated the potential friction problem we had in our race to the wall robot while also moving in every direction, important with a 2 wheel system.
While designing our robot we decided that we would have an endoskeleton for ease of maintenance, such as switching batteries, maintenance with wiring, ability to change ports if necessary and powering up our robot. The power switch was easily accessible from the rear of our bot, and the whole bottom of the robot slid apart, each half connected to a different part of the battery pack, for ease of changing batteries.
Our motors were fixed to our chassis using cable ties. Throughout our testing they held fast and decided that they were good enough for our final bot.
With our new wheels and motors we had some extra space, not enough to fully realise our original wedge concept, however we decided that the core concept of the ramp was worth keeping. We would need to develop an unfolding, space saving ramp.
We achieved this goal by very practical means. We taped a reinforced cardboard sheet to the front of our bot, in a way that was finely enough balanced that if our robot changed direction, the ramp would fall. In testing this ramp would stay up until we reversed, then would fall over 95% of the time.
One issue we did have in our tests was that our robot would rotate on the axis of its wheels when encountering a heavy object. We remedied this by adding a stabiliser leg to the rear. On testing this, we found it to be extremely efficient.
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