42 Points!!

Footage from the UK Finals on 05/01/09 of the robot achieving its maximum score of 42 points.

Claw & Software Revisions

As the day of the UK final approaches, focus has been put on getting the system as efficient as possible. During the rebuild, the claw was modified, bringing the lower support section closer to the bottom in the hope that it would support the lower part of the column better. This didn't work as planned. It turned out that this design made the tube too stiff, so it didn't flex in the right places. This put the claw's pressure on the higher discs, meaning that it wouldn't collect more than 2 or 3 discs at a time.

The design has now been reverted back to the original, with the support claws higher up, and a rubber band pulling the bottom of the claw into a funnel shape to support the column where it needs it most.



Also today, the team has started making changes to the program, to make the stacking process more efficient. The plan is to stay closer to the stacking zone during construction, so that less time is wasted during transit.

Obstacle Avoidance

The team are using 2 Sharp infra-red sensors to find the position of other robots on the table. Both sensors are placed just higher than the column element dispensers to try to avoid the robot reacting to anything other than another robot. Both sensors face forward.

The team calibrated the sensors and created a sub program on the main drive board to tell the motors to react. When the sensors see another robot which is positioned in the way, the motors will stop for 0.7seconds, then if the sensors still see the robot, the motors will reverse until the other robot is gone, then attempt to return to the point it left.

Rebuild

During the second and third weeks of the Easter break (13th to 22nd April), the team rebuilt the entire robot with new parts. (Before to the left and after photos are below).

The laser cut MDF which provides the different levels was painted off-white.

The MDF parts that make up the claw were remade in white, opal acrylic; this reduced the friction on the guide rails.

The lintel mechanism was remade in laser cut white acrylic for strength and accuracy.

The PTFE casters were redesigned to be more adjustable; so as they ware down they can be moved, allowing the back of the robot to maintain the same height.

Poor quality micro switches were replaced with industrial standard switches.

The tapered shape at the front is widened allowing more room for error when collecting column elements.

Last but not least, the guide rails, track and vertical encoder was extended. This now gives the claw a 50mm higher lift. The team plan to use this to place 2 extra column elements on top of their original tower. This will raise the total points per match from 29 to 42.

Last few jobs are
- The pull cord
- Obstacle avoidance
- 90 second shut down timer
- Fine tuning all programs

Further devolopment with temple construction

This video shows the robot building a temple when there is already a temple of the opposing colour in the same position that it wants to build. Also the robot collects 4 discs in the first row so it doesn't bother to drive around the rest of the grid, it goes straight to the stacking point.

Lift Mech Improvements

The program has been modified to speed up the disc collection process. This means that the robot spends less time stopping for discs, and so will allow us to arrive at the construction zone earlier.

New Sponsors

Also this week, after a few weeks in planning, we can officially welcome our sponsors, Phoenix Dynamics.

"Established in 1994, Phoenix Dynamics is a leading supplier of interconnection solutions to the Defence, Automotive, Rail, Nuclear and Control System Industries."

Check out the website, www.phoenixdynamics.com for more information on the company.