finishing touches

Only days until it is time to present our final prototype and we have some bugs to sort out and features to hash out. The skirt is mostly working. We need to workout the right level of taught-ness for the string on the pulley along with the right number of revolutions for the motor to be programmed. In addition, the skirt is a little slouchy. We need to create a better support system for it to look good and hold up.

Finally, we need more pizazz for the final presentation. We got some funky sleeves in the works. We plan on embedding LEDs to it that will light up when the transformation is complete with a switch activated by putting my hands on my hips. We also have a crown that might add to the princess aesthetic. We got the Disney princess feel, why not go the whole 9?

mechanics issue #2

Today we finally got the skirt working with the Lego motors. We found, however, that we need to do something not typical to a hoop skirt. The partial reasoning behind the hoop skirt was to cover the bulk of the motors but it was also to help with the alignment issues we were having with the previous design. The trick is to pull straight up or down. Now we are pulling at an angle because the angle of the skirt grows over time causing it to end up at a slant.

An image of a pulley

As you can see there's the string to pull and a spool type mechanism for the the string to be pulled on.

To solve this, we came up with the idea of making an inner support system. Having an inner loop attached to each hoop attached to the skirt so that the strings can go straight down but still affect the whole skirt. To attach the inner and outer hoops, we have reinforced cardboard “beams” (if you will) that are attached with lots of duct tape to the hoops.

Now we have a smoother pull and nearly no alignment issues!

higher fidelity prototype & mechanics issue #1

We cut the black satiny fabric into a shape that would do away with all the extra fabric to help with the weight of the skirt. The hoops were loosely sewn to the skirt. We fond that the hardest part of the twist ties was to find something strong enough to get rid of the locking part of it. It made a tear drop shape more than a circle. After some digging in the engineering lab we found some sheers and used those.

For the motors, we had to create the means of powering them. They spun insanely fast but they were having a hard time pulling up the lightest loads. What was more disconcerting was the issue of the pulley mechanism. The system we have figured out is one where the skirt hoops are threaded through with string and the string is attached to a a spool which is attached to a motor. Once the motor is started in a direction, the string will wrap around the spool, pulling the hoops and skirt up. If we wanted to drop the skirt, we’d just need to reverse the motor’s direction.

The issue was that the DC motors did not work with the Lego pieces we had so we would need to custom make the spool if we were to use the DC motors. In addition, we would lose the up and down functionality for the most part because we had not figured out how to program the DC motors.

So it was back to the drawing board.