Wednesday, 5 May 2010

Sneak peek of the NXT Adapter prototype

Not too long ago i wanted to make a NXT adapter for some cheap and constant power like what Philo did, but unfortunately i couldn't get all the components i needed to make one. So, i consulted a friend of mine, who is also a Mechatronics engineer whose specialty is in designing electronic circuits O.O So after some careful thinking and component sourcing, this is what he came up with n_n

notice anything different about this NXT ?

Here's a better view of how the circuit board looks like. The design was simple and effective, it works just like LEGO rechargeable battery pack + LEGO adapter, but at a fraction of the cost of course =) The aluminium plate secures the circuit board firmly to the NXT through friction lock, and an adapter socket was carefully placed to allow the easy connection to the adapter.

i made a simple program to measure the voltage supplied by the adapter and it registers a healthy 9.11 volt. When i connect the NXT to 3 motors and run all of them at the same time, the voltage dropped to around 9.05, which is still pretty decent.

So what's so great about using an adapter over normal or rechargeable batteries and when do you need it ?
  • When you are tired of wasting precious $$ changing batteries.
  • When you are tired of having to wait for your rechargeable batteries to fully charge.
  • When you need constant voltage and power, especially when you are building some stationary projects (very useful for schools who participates in open category =D )
  • When you want to make your robot lighter.
Keep in mind that this is just a prototype...the final product will look a lot nicer and much more solid as my friend and I intend to produce limited units for the benefit of those true mindstorms enthusiasts.

Any comments are welcome and do let me know if you are interested in laying your hands on one of this =)

Monday, 5 April 2010

Vertical Limit concept bot

Here's a ONE concept robot i sketched for the Vertical Limit event :


The robot has 2 swinging arms attached to the main chassis of the robot. The swinging arms each has one or more rotating tires attached to them for gripping & climbing the poles. A simple hook mechanism is attached at the end of the swinging arms to push the ping pong ball into the basket.


  1. 1 motor for moving the robot front and back with no turning ability. (since that's all you need to move from pole A to pole B)
  2. 1 motor for swinging the arms to the front to hold on to pole A and swinging to the back to hold on to pole B.
  3. 1 motor for the rotating tires on the swinging arms for climbing the poles.


I did not include the sensors in my sketch but you may use a Touch Sensor on each side for detecting when your robot has bump into a pole, or you may use an Ultrasonic Sensor if you want a non-contact option. You may use another Ultrasonic sensor for detecting when your robot has reach the top, or you can use light sensors to detect the different sections on the poles but remember the colour of wrappings on the poles are random, so you've been warned here. On the way down, you may use a third Touch Sensor to detect when your robot has reached the ground. As for moving from pole A to pole B, no sensors will be required since your robot can only move straight.

If you are daring enough, you may even choose not to use any sensors and rely solely on rotation alone but i wouldn't recommend it unless you are pretty confident with your design.


the program for this robot should be very straight forward, maybe something like:

  1. move straight until touch sensor 1 bump into pole A
  2. climb pole A until ultrasonic sensor 1 can no longer "see" the pole
  3. climb down until touch sensor 3 hits the ground
  4. whole robot reverse until touch sensor 2 bump into pole B
  5. repeat step 2 & 3.

Please bear in mind that this is just one of the many possible ways of solving the challenge. But my message here is always put your ideas into sketches & drawings using simple shapes and then list down the tasks your robot needs to complete, the constraints/limitations of your design, before you actually build the real thing out. Too often the students tend to dive straight into building the robot without having the big picture and eventually they get stuck very quickly.

So i hope this post helps to give you some idea on how to conquer the vertical limit challenge & also how to tackle a complicated problem in a simple way - put your ideas on paper first (^_^)

Saturday, 3 April 2010

New Arrivals by Yoshihito Isogawa

Yoshihito Isogawa is one of the more famous LEGO innovator, creating simple mechanical LEGO objects while keeping it simple.

Anyone who is new to LEGO Technics should download his PDF file (LEGO Tora no Maki). It has got many innovative ideas, and the simplicity of his designs makes us all wonder, "How does he come up with such great yet simple ideas??".

He is definately a GURU or better still, a LEGEND when it comes to LEGO...

Main Works Model Gallery click here.
Small Works Model Gallery click here.

Please note that, even though it is all written in Japanese, the simplicity of his designs and the photos that shows his designs makes all his works universal, without any language barrier...

Wednesday, 31 March 2010

Vertical Limit (Upper Secondary) too tough ?

Now that FLL is over, it's time to start working on robot for NRC 2010 that is going to start in another 2 months time.

One of the most common complaints i heard from teachers and students were regarding the difficulty of Vertical Limit - the upper secondary event for regular category. Since no sample solutions are being provided this year, most schools (at least the ones i know) must be scratching their heads, or, should i say, pulling their hair from their scalp just to come up with a workable solution.

To add more salt to the injury, the recent update on the rules requires the robot to move from pole A to pole B AUTONOMOUSLY !!! surprise, surprise (O.O) Muahahaahaha....

It was not the organizer who wanted to play a prank on all the schools who participated in NRC 2010 but because the WRO committee keeps changing the rules as NRC 2010's events are based on WRO. (being an ex-Sasbadi trainer, i can attest to this )

This got me thinking a little - how on earth do you make a robot that can climb a pole 25mm in width, collect a ping pong ball, come down, move on to the next pole ALL BY ITSELF, and repeat the same thing again while using only 1 NXT controller, 3 motors, & 4 sensors (max) ?
I have been sketching up a robot using simple shapes & once i am done i will post up the sketches to share with you guys, so stay tuned :)
p.s. i'm not good in drawing :P

Tuesday, 23 March 2010

Videos of Team "The Light Warriors" at FFL 2010

Congratulations to Team "The Light Warriors" from REAL International School, Hulu Langat who won Best Overall Robot Design award at the recent FIRST Lego League (FLL). The team comprised (in alphabetical order of surname):

  1. Thavish Annal
  2. Sabrina Chia Chee Teng
  3. Massimiliano Daldoss
  4. Koh Phey Faye
  5. Melissa Lim May Lyn
  6. Shue Yuann Shin
  7. Kabilan Subramaniam
  8. Eddy Tan Jia Cheng
  9. Wayne Tan
  10. Jonathan Yap

The team is also accompanied by:
  1. Daniel Tsen (Team Manager)
  2. Erol Hujdur (Coach)
  3. Ong Poh Lai (Coach)
  4. Eric Tan (Coach)
  5. Ong Poh Seng (Coach)

Here are the videos that depict performance of Team "The Light Warriors" during the two-day event at National Science Centre, Kuala Lumpur.

Project Presentation

Technical Presentation (Part 1)

Technical Presentation (Part 2)

Mission (Round 1)

Mission (Round 2)

Mission (Round 3)

Award Presentation

Keep up the good work!

Saturday, 20 March 2010

FLL 2010 - Smart Move - Best Overall Robot Design Award - Real International (Seri Suria)

First I would like to congratulate all the kids from Real International (Seri Suria) for a job well done in bringing home a Prize (Best Overall Robot Design Award) from the FLL 2010 Smart Move competition held on the 17 & 18 March 2010.

Preparations were intense, and all of the kids only really had 4 full days to complete the robot, practise the missions and organise the presentation.

I would also like to thank Daniel, Erol, Poh Lai and Poh Seng for putting in all their time and effort into preparing the kids. All would not be possible if everybody did not play their own role.

I would say, a Prize is always nice, but I guess we would have work even harder for the FLL 2011, as I noticed the Team to beat would be SJKC Jalan Davidson, of which their robots went flawlessly, perfect in a sense. Their robot was well taught with great innovation and ideas.

Attending the FLL for the first time was a different experience. I guess it was the different methods they used to judge needs sometime to get used to. Our presentation was not as well done as it should. We didnt have props and costumes like the other teams.

I guess overall, for a first year contender in any Robotics competition, we did great. We just have to buck up, as the other schools out there are years ahead, in terms of LEGO Robotics.

So, no rest for the wicked, since the NRC 2010 question is already out... I guess training would have to start.... again.....

More photos of FLL 2010 at Jason's Blog (Sasbadi Staff)

Thursday, 18 March 2010

NRC 2010

The events for NRC 2010 is as follows

Regular Category
1. Primary School - Adventure Race
2. Lower Secondary - Treasure Hunt
3. Upper Secondary - Vertical Limit

Open Category
Theme: Robot Promote Tourism

Full details on rules available here.

Registration form available here. Closing date is 30 April 2010.

Good Luck to all.

**Details are obtain from Jason's blog (Sasbadi Staff)