Blog – Page 4 – A Posteriori

January 25, 2018March 16, 2018

Mechatronic Talent Show @ Temasek Primary

Last week we started a 20-week recreational Robotics CCA at Temasek Primary. The cohort is called The Roboteers.

I partnered with Zahab G., our most recent addition to the Aposteriori family. Zahab has a Master’s in Chemistry and has been working with children in holiday camps and as a tutor for GCSEs and other secondary school-level tests. Zahab is enthusiastic and energetic – just the right mix of smarts, playfulness, and curiosity that can help ignite a pre-teen’s imagination.

We decided to coordinate a Robot Talent Show/Parade for this course, as opposed to the tired Line-Following, Sumo or other types of basic robotics competitions. The students are being tasked to complete a very open-ended task – exhibit a robotic talent of their choice. The first week they had crazy ideas like fire-breathing dragons, and death-defying daredevil robots. The second week we started prototyping and quickly settling on likelier choices – like pickers/sorters/collectors, art-makers, uniquely-actuated machines, and obstacle avoiders.

At the end of Week 2 prototyping, we still have some unsettled teams, but the process is becoming clearer as each team is asked to share their ideas with the rest of the class. The next challenge is to stir away from prototyping and into actualizing without giving up on the initial idea when implementation hits difficulties – a likely event on all such projects. In any case, the students seem very engaged in the process, with a few minor exceptions, and are enjoying themselves quite a bit, so far.

With 36 students and just 2 instructors, I find it challenging to manage the teams and keep them on target at all times, but luckily we have a disciplinary team of teachers in the room with us to keep the students in check if things get out of hand and a whole class is derailed due to nonsense.

Next week we will begin more technical discussions on drivetrains, gears and other simple machines. Look out for updates on the Roboteers Talent Show!

January 11, 2018March 16, 2018

Wall Climbing Robot Race – Singapore Robotic Games 2018

Last week, as I was getting excited about my work with FIRST LEGO League at the Innovation Lab (see last post), I spent some time scouting other local and regional robotics competitions. I happened on a very useful list from a competitor. It led me to investigate the Singapore Robotics Games (SRG) as a general platform for expressing our own innovative energy. I immediately got motivated to register our team of crack enthusiasts to showcase our talents, abilities, and our drive. Participating in and winning a robotics competition is both immensely rewarding and very valuable from a marketing standpoint – a powerful story to tell kids, parents, teachers, administrators and partners when we try to tout our product. As this event is organized by Singapore academia, it is more about fostering rapport between various organizations who have a stake in robotics research and its integration in academia and industry in Singapore, and so registration fees are waived by the organizers, who co-sponsor the event with the Science Centre and its government arm – the Science Centre Board, which is part of the Ministry of Education.

Shenghao (resident hacker) and I perused the competition documentation and decided to go for the Wall Climbing Robot Race, because we believed the challenge was simple enough to get at least partially right in a short amount of time. The historical participation rates for this event were not overwhelming, which was another bonus for us. We quickly ensnared the support of Cort, and immediately became embroiled in design discussions and strategies for winning. Laven (resident martian expert) joined our group as well, and I registered our 4-person team officially, once we had a consensus that this was worthy of our time and effort, and that we would all be OK making complete fools of ourselves in the worst case.

Our current design is basically a car that climbs walls and stays upright by applying some force directly towards whatever surface it is on – it takes over for or fights against gravity when the plane of motion changes with respect to it. We are using electric ducted fans to try to achieve this. Currently we have a fairly complete design, but missing a few of the parts – namely, power switches for high-current applications, and wheels and tires. We also need to do some design work to get around any kind of wheel slip in our car, that would disorient it off its planned course – go straight. The variance in reflectance properties of the 3 surfaces we need to drive across seem to be complicating this to some degree.

Our budget of $500 is quickly being eaten away from paying premium prices for electronics, which we are sourcing locally, instead of through our usual, cheaper, global trade routes, simply for the expediency of time. We have about $150 sunk in drive and thrust systems (EDFs, gear motors), another $100 or so in the power system (with some spent on reserves for the sake of rapid-ish prototyping), and say $50-100 allocated for chassis, controller, sensors and the rest of the electronics, a lot of which we already had.

We’ve done about 3 days of work, and I foresee about 3-5 more before we have a testable platform. Depending on the sanity of our design choices and integration work, we may be close to done at that point, or scramble back to the drawing board, with very little time to spare before the competition.

No mountain too high for A Posteriori Wall Climbing Robot Team!

January 10, 2018January 11, 2018

FIRST LEGO League Kickoff at LEGO’s Innovation Lab

As of Sunday, Yoni is collaborating with Kwee Lin Yap at LEGO’s Innovation Lab (Science Centre) on a set of workshops where we are coaching teams for this season of FIRST LEGO League (FLL).. This season’s theme is all about HydroDynamics – the human water cycle and its current challenges and future innovations.

The teams have a lot of work cut out for them, and it’s a challenge getting full buy-in from every participant. It’s amazing how quickly they can get into problem-solving mode, how creative they can be in solution finding and challenge approach. However, we had a lot of problems with team work and core values, which we will have to build up for a lot of the season.

Yoni has a long history of volunteering with FIRST on various programs:

2005 – event volunteer at the New York regional FIRST Robotics Challenge (FRC)
2008-’09 – mentoring Brooklyn FRC Team 1600 for two seasons
2012 – volunteer field technician at Singapore’s FIRST Tech Challenge (FTC)

FIRST has made Robotics and Engineering as popular as athletic leagues, with all the important focus on professionalism, sportsmanship, teamwork, cooperation, and respect. We are proud to make it available to children who are unable to be involved with it through their school or other organizations.

Let’s Flow!

December 30, 2017December 30, 2017

A :Bit of Fun @ Muhammadiyah Welfare Home

We managed to find the time for a half-day, multi-disciplinary workshop at the Muhammadiyah Welfare Home for at-risk youth. The computer lab at the center was limited to fourteen PC’s, so we had a group of fourteen kids, and we chose to use block programming as a medium, utilizing the popular and relatively cheap BBC micro:bits.

Stage One

Our team included Yoni (myself), Shenghao (resident hacker with only good intentions), and Zahab (master chemist with a heart of gold). We wasted little time on formalities and niceties and started the secondary school-aged kids on sequencing, repetition automation, and conditional foundations using the Microsoft-provided, and Google Blockly-based simulator – social enterprise can bring out the best in everyone! By the end of the first hour, the attendees had already designed a digital book of microMojis, original taglines, and built-in jingles, complete with pagination logic utilizing the micro:bit’s A & B buttons.

One PC was on the fritz, so Shenghao multi-tasked between troubleshooting student code and troubleshooting PC hardware. He had all fourteen working by the time we left…

Stage Two

After a short break, the class returned to begin their second challenge – authoring their original, digital music. At this point we handed out the actual micro:bits, so the students could start downloading their code from the simulator and into their own pocket PCs. The brand new :bits took a bit of wrangling and calibration to setup, but we were all back to coding in a few minutes.

Once a student had completed their musical number, the obvious next question was – “how come my micro:bit doesn’t play sound?” Which is a perfect segue to explaining the available actuators and sensors on the micro:bit. As far as actuation, there’s not much more than the 5×5 LED matrix. So, everyone was relieved to find we brought alligator clips and piezo buzzers along. If we had more time, Zahab could probably have tantalized the students with her tales of piezoelectric effect on various materials. Alas, we were anxious to move on to our next mini-module.

Stage Three

In the last hour, some students had enough foundation to be able to explore on their own and we allowed them the free time to do as they wish. We strongly believe in open-ended projects, self-exploration, learning by trial-and-error, and mastery through play. For instance, Zahab worked with one row on Radio blocks, which utilize Bluetooth broadcasting for inter-micro:bit communication. The kids in that row had fun messaging each other micro:tweets.

For other students, we devised a mini-challenge to utilize Sprites in the Game blocks menu to create a simple Cat and Mouse game using various inputs and the LED matrix visualization. This was a stretch project, and not all completed it successfully. The looks of joy and appreciation on everyone’s face – after the initial cries of frustration – betrayed the fact that, by and large, our mission was accomplished.
Another of our strong convictions and inherent lessons in our activities – it’s OK to fail!

In Conclusion

When we left, the attending staff member suggested we could return soon, as the fourteen students we managed to fit into the computer room were just a fraction of the boys who would be interested and could benefit from our programs. We look forward to meeting more of the Muhammadiyah community on our next visit!

Like to join us in our volunteer sessions? Have the right STEM skills, want to do volunteer work, but don’t want or don’t have the resources to do it alone? We organize volunteer STEM courses whenever we can and will be happy to have you join us. We welcome everyone, from students to experienced robotics trainers. Just drop us a mail at info@aposteriori.com.sg

December 29, 2017December 30, 2017

Volunteering at Boys Town

Robotics can be a useful gateway to building up an interest in STEM subjects among kids, but it is also a great way to engage with at-risk youth.

Last week, Yoni and I visited Boys’ Town at Upper Bukit Timah to conduct a one-day course on Lego robotics. I haven’t done any volunteer work in a while – been too busy (…excuses; I know…) – and it was a great way to get started again. After a brief stumbling around due to a Google Maps error, I found myself in a small computer lab with 6 shelter kids sharing 3 Lego EV3 sets.

Getting Started

The kids were energetic but well-behaved. Learn fast too! The first challenge we set for them was to build a simple wheeled robot, but one of the teams chose to build a much more challenging four-legged “Puppy” instead. I’ve always believed in encouraging kids to find their own interest and direction, and am glad to see them taking the initiative to choose a different path. The other two teams are no slouches either, and were adding new mechanisms and decorations to their basic robot.

The most fun was had with the programming challenge. The kids had to race their robots around a bend, and were constantly measuring the distance and refining their program to get the best timing. One team found the trick of using a bigger wheel, but it didn’t take long for the others to learn the same.

A Pungent Interruption

It so happened that it was harvest time for the durian tree in the Boys’ Town compound, and a durian party was planned for in the afternoon. Robot may be fun, but durians are irresistible… although not for me, as I’m one of the rare few Singaporeans who can’t stand the smell. Still, I’m not so cruel as to deny the kids their durians, so we took a few minutes away from the robots to enjoy the party.

Flying Robots

Yoni also brought along a Parrot Mambo Minidrone for the kids to try out, and it was also my first time having a hands-on experience with that particular model. With it’s height and horizontal movement sensors, it had amazing stability for a drone of its size and price; leagues ahead of my old Hubsan. For teaching STEM, it’s not as good a platform as an EV3 or a micro:bit; the limited input and output capabilities restrict the complexity of the program that can be written. Nevertheless, the kids had great fun programming the drone, and learned a bit about sequencing and movements in the process.

Incredible Experience

The unexpected interruption with the durians left us with less time than planned, but the kids still managed to achieve most of the challenges. Most of them managed to complete the “Search and Locate” challenge, and were making good progress towards the “Grab and Go” challenge. It was amazing watching the kids experimenting, discussing, thinking and concentrating, it’s what robotics does best; getting kids engaged in learning.

The session would not have been possible without the kind support of the Boys’ Town staff (…sorry for the sticky tape marks on the floor!). Both Yoni and I would love to help out again and will be looking forward to our next visit.