First of all we decided to increase sensitivity of light sensors. Robin updated it on software level such that difference between tape and table will be detected more significantly.
Then we decided to increase precision of encoder. Initially, it was connected to front wheel axle directly. It has two disadvantages. First one is that length measurement will be disturbed by curvy trajectory caused by rotations of front steering wheel. Second one is that one full rotation of front wheel will be equal to 16 ticks which is not sufficient for small distance measurement precision. After analysing them we decided to improve mechanical design. We have made following changes.
1) Moved encoder from front wheel to the on of rear wheels
2) Connected encoder to the axle indirectly by using clutch of two ratchets. Ratchet with bigger radius was connected to axle of wheel and transfers rotations to the ratchet with smaller radius. This second ratchet is connected to encoder. As a result, one full rotation of wheel will be equal to several rotations of encoder. Thus, precision of length measurement will be increased
3) Differential connection was added to rear axle.
These changes improved chassis of rover and will yield easier programming together with better results for both assignments.
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