Robotics: Part 5

This should be the final installment in this series of robotics-related blog posts, until the next competition, if I'm requested to help by then. This post is about the best and greatest robotics project ever produced by the robotics club me and my friends founded back in 2008. It is the culmination of a superb idea from today's members, the expertise of the most knowledgeable robotics members past and present, and the efforts of the people who contributed to this project.


National Robotics Competition 2010 Open Category (State and National Levels)
Theme: Robot Promote Tourism
Team Members: Charissa Chan, Daphne Song, Lee Yee Yen

Just before the state level competition, I was contacted by the advisor teacher of the robotics club to help out on their open category robotics project. The project was basically a 'house' with a screen on the front which displayed a shadow puppet show. Behind the screen were moving clear plastic cutouts that moved, and an overhead projector which projected light and a background for the shadow puppets.



The idea was superb, combining 2 elements of Malaysia's heritage. Malaysia is a country with many different races and religions. Showing off the many varieties of dances in the country was a superb way of promoting tourism, as it depicts the multicultural society of Malaysia in its most beautiful form. "Wayang kulit" literally translated to "Skin Theatre" is a traditional Malay pastime that was used to provide entertainment to the villagers. It is native to the Malay isles, including Peninsular Malaysia. While traditional "Wayang Kulit" performs folk tales and stories, the "Wayang Kulit" in this robotics project are about the dances of Malaysia.

The main dance in the project is the Sumazau dance of the Kadazandusun natives of Sabah:





I started out by redesigning the shadow puppet's mechanism. The original mechanism places too much strain on the Lego parts, and does not move the arms of the dancers well at all. What was actually needed was for a shaft to extend and retract, pushing the arms outwards and inwards continuously. I achieved this by connecting a shaft onto a large gear that rotated, and extending the shaft to the bottom of the controlling mechanism to a loose guide, so that the shaft extended linearly while the gear rotated. The whole mechanism was mounted on top of a motorized set of wheels that moved the robots horizontally across the house (i.e. left-right on the screen)



I did not do much beyond that, as they were leaving for the state-level competition the next morning. That, however was the main part of their performance, and was rather crucial for them to win.

And win they did. They managed to win Gold in the State-level competition, allowing them to compete in the national levels as state representatives. However, the team decided to go for a completely revamped project for the national levels, like we did 3 years ago. And like 3 years ago, there wasn't much time for such a load of work, so it was time to bring out the big guns:



From left to right: Alex Lo, Aaron Raj GC, Jason Lee

I called my old robotics team members from 2007 to help out. It was just like old times. Aaron Raj GC, Jason Lee and Lee Joeshua were still in Tawau, so they joined in the fray. Between me and my team, plus the current club president, we had about 2 decades of experience and several projects under our belts.

I started with the Sumazau dancers. During the state level competition demonstration, the dancers were prone to collision, as their running tracks had to be as close as possible. Rather than improving the wheel drive system, I opted for a tracked system to improve on its reliability. After years of experience, this was possibly the best set of tracks I've ever made. It was strong, rigid and allows for the moving mechanism to attach to it perfectly:




I modified the dancing mechanism to incorporate a pinion gear and various attachments for it to move on the track without derailing.








While I was doing that, Joeshua, Aaron and Jason built the lion dance puppet control mechanism. Rather than mounting a real moving lion, I suggested a simpler plastic cutout controlled by an overhead mechanism. The mechanism runs on a track mounted on the top of the house, and controls the lion dance plastic cutout using fishing wire like a marionette. The mechanism allows the 'lion' to 'jump' up and down the stilts (which was projected using the overhead projector) according to the rhythm of drums and cymbals. I added another motor that pulled a line connected to the 'lion' head to allow the head to shake (something often seen in real life lion dances), and started programming the 'lion' to dance.







View from the outside:



We also improved the alignment of the roller mechanism for the slides passing through the overhead projector, which was designed by the team members:




The final programming that synchronized the performances, curtains, leaflet dispensers, lights and sounds was done by Alex Lo, the current president of the Robotics Club. I helped out by developing the raw programs for the dances, and developing new methods for the various NXT controllers(about 6-7 of them) to communicate with each other. After the bad experience with Bluetooth 3 years ago, I suggested a light-to-light-sensor direct wire system, whereby an NXT switches on another NXT by turning on a light, which activates the light sensor of the other NXT. This was used in the end to complement their Bluetooth network, which worked.

The automatically drawing curtains, lighting systems, leaflet dispensers and other aspects of the project including the house, with its atap leaf roofing, bamboo walls and various decors were made by the team members along with some support students, guided and supervised by the advisory teachers.


House under construction:


Leaflet dispenser:


Master controller+ iPod player:


Automatic curtains:


During the competition:

Left to right: Daphne Song, Lee Yee Yen, Ms Koh (Teacher adviser), Charissa Chan

After so much work, it was payback time. The team won Bronze in the national level competition which was the greatest achievement the club have ever had so far. After so many failures and setbacks in past projects due to various reasons, the success of this project definitely made up for them. Next stop for the club: the World Robotics Olympiad.