Project lab 6 - Distributor platform construction

Date: 08/06/2013
Duration of activity: 15:00-18:00: --> 3 hours
Group members participating: Ole Rasmussen and Kasper Føns

1. Goal

The goal of today is to rebuild the best car found by experimentation from the previous lab report (the car from experiment 2a). We will also build the distributor platform around the tray on which the distributor car is to move on.

2. Plan

The plan for this session:

• First we will rebuild the best distributor car, which was the one from experiment 2a.
• Build the distributor platform

3. Rebuild the best distributor car

We found that the car from experiment 2a was the best. Since we have dismantled it for use in later experiments, we needed to rebuild it again. It was quite easy to rebuild though.

4. Distributor platform

We need some kind of platform around the Lego tray so that we can drive on top of it and deliver the bricks in the correct compartments. Our first idea is depicted in Figure 1. Our idea is that the car drives on two distinct pieces:

1. The distributor platform, standing on the ground. The tray fits neatly inside and cannot move in any direction.
2. The distributor bridge, which drives on top of the distributor platform. The car controls both the distributor bridge and the car itself, and the distributor platform is stationary.

Figure 1: First platform idea. The distributor platform stands on the ground and the trays fits in. The distributor car drives on the distributor bridge which in turn drives on the distributor platform.

After having built the distributor platform, we discovered one major obstacle. Figure 2 shows the problem. We found that trays are not rectangular, which does not have to be a problem it itself. However, it becomes a problem when the longest axles need to point in one direction while the longest beams need to point in another. That means that if we position the trays in the same direction, the car would need to drop the beams in one direction and the axles in a direction perpendicular to the beam direction. This is simply not an option, so we need to come up with a better solution, but we don't have more time in this lab so we'll look at it the next time.

Figure 2: Tray problem. Trays are not rectangular. Both trays are positioned with the long side horizontally. We found that the largest axles would then point vertically while the beams would point horizontally.

5. Conclusion

We constructed the distributor platform but discovered that it cannot actually be used since positioning the trays in the same position implies that axles and beams needs to be dropped in different directions, something the distributor car cannot handle.

6. Next lab

In the next lab we will look at a solution to the platform problem.