Moonbots 2011 Playfield & Mission

I was invited over to give the Techno Inventors a hand in the Phase 2 of their Moonbots 2011 competition. Below is the overall playfield.

It is actually very huge,  with 5 x 5 large lego plates as the base! The whole playfield is huge, with the walls at the back with Earth as the background was really cool. There is a landing pad which is black in colour situated at the left side of the photo.

These are 4 of these (Black & Orange) object to pickup from the field. It is called Helium-3 and worth 15 points each. Please note the 4 brick high wall ridges that the vehicle would have to traverse to get to the other side of the play field!

This is a photo taken low within the Crater Canvin. Please note that it has been filed with 2000 orange 1x1 bricks making it rather impossible for a vehicle to traverse into this crater, let alone get out of it, specially when it is surrounded with a 4 brick high ridge!!?? There are also 4 Water Ice element (White & Blue) object to collect while in here. Each is worth only 10 points. Please note the backgrouns has the red marking and some plus signs.... it is known as the Heritage Artifacts. Capturing a image of it will grant you 20 points!

Here are the breakdown of the points on the Playfield (350 points total)

• Lander Dismount (leaving the base/landing site) - [20 points]
• Discover Water Ice (pick up Blue & White objects) - [10 points x 6 units]
• Survive the Lunar Night (Stay on top of the Peak of Eternal Light for 5 second) - [30 points] 
• Discover Helium 3 (pickup up Black & Orange objects) - [15 points x 4 units]
• Capture Mission Video (video the entire run of the mission) - [20 points]
• Photography the Heritage Artifacts (video the Heritage Artifacts) - [20 points]
• Return to Base (touch the base) - [20 points]
• Return Elements to base - [x2 points of each element]
• Touch Penalty - [minus 50 points each time]

Opinion and Play difficulty of the Moonbots 2011

• Playfield is build with Lego Plates. Surface is studed making the movement of the vehicle inaccurate
• Ridge is at least 4 bricks high, make it difficult for the vehicle to traverse over it
• Crater Cravin is filled with 2000 pieces of 1x1 bricks making it almost impossible to be moving accurately within the crater. 
• Getting out of the crater would also be impossible as there is no traction on the wheels.
• As all the elements are very similar, designing only 1 arm to collect/pick up the elements is required

Overall, it is no easy mission. Compared to FLL or NRC it has its own challenges. Please note that there is only about 6 weeks time provided to complete the mission as well as the other activities as per the Moonbots requirements.

Total scoring for Phase 2 is as follows

• Blogging requirement met (5% weighting)
• Robot design proposal turned in on time and the design matches the robot construction (15% weighting)
• Creativity and technical merit of STEM Outreach project (40% weighting)
• The Science Mission Score achieved during the Live Mission Webcast (40% weighting)

Techno Inventors of Sekolah Seri Cahaya is Moonbots Finalist!

We would like to congratulate Techno Inventors of making it to the finals of Moonbots. For those who haven't heard of the competition, you could head to moonbots.org for more info.

To see the top 20 finalist, you can click here.

Better still, click here to view their team websit.

Malaysia is 1 of the 2 non-US teams in the 20 finalist teams. The other one is from Chile.

Check out their Video selection below that allowed them to make it to the finals!

The oldest student is only 13 years old and the script was done mostly by the kids. I guess the humor element made them stand out.

Once again, congratulations on making it to the top 20.

Line Follower Algorithm - Which is the best?

Single Light Sensor - Bit logic method (1 Min 59 Sec)
Read full post here.

Single Light Sensor - PID method - Smooth (1 Min 29 Sec)

Read full post here.

Single Light Sensor - PID method - Over Correction (53 Sec)
Read full post here.

Dual Light Sensor - PID method - Smooth and Fast (33 Sec)
I have not posted about this Line follower that I had built. It moves really fast and because there is 2 light sensors, it is able to adjust and move along quickly. I am trying to optimize the dual sensor to go even faster. Will post the outcome when I am done.

Line Follower - PID Method - Over corrected!

This post is a followup to the previous PID Line Follower post, of which I was using the PID method. As you would have noticed in the previous post, the Line follower robot was moving very smoothly over the black line, however it was extremely slow!

Please note that the line follower robot is only using 1 light sensor, the left one. The robot has been built with 2 sensors for future test algorithm.

In this followup post, you'll notice that the robot moves along at faster rate, but the robot seems to be constantly oscillating, with a few occasion that it manage to reach equilibrium. This is because the robot seems to be over compensating. The reason that this could happen is because is because the robot's feedback loop is too slow to react, and is NOT able to compensate quick enough, causing it to go into an oscillation mode. I would have to re-code the robot using NXC or RobotC to overcome the speed issue.

Another possibility is because of the variables that I have used to adjust the robot for a faster speed, rather than a smooth moving robot. Maybe the setup variables is inaccurate, thus the robot is unable to hit its equilibrium. However in the video above, the robot did reach an equilibrium state (moving straight) occasionally.

I will post the source codes in the future post after I have done investigation on how to make the robot move faster yet smoother.

If anyone has manage to complete the above task, please post in the comments how you manage to make the robot move fast yet smooth with 1 light sensor.

Line Follower - PID Method - Smooth

I hope most of you have read the Bit Logic line follower algorithm. Next I will explore the PID method, which I have been reading alot lately on the Internet. I reckon, for most high school students understanding just the "theory" of PID will be enough to put you through college :p

Please note that the line follower robot is only using 1 light sensor, the left one. The robot has been built with 2 sensors for future test algorithm.

Anyway, if you would like a very detailed theory, calculations and formula for the PID method, please follow this link.

If you have watched the video, you would realised that the robot tries to correct itself to stay in the middle, between the black and white areas, as shown in the image above. After a few oscillation, it would be moving along the grey area (between the white and black).

The graph above shows the Motor power output vs the readings from the Light sensor. As you can see, the robot will always try to keep within the Grey area (dotted line B), which is the equilibrium. When the Left motor and Right motor, is travelling at the same speed, the robot is actually move straight.

When the Light sensor is above the White area (dotted line A), you'll notice that the Right motor will stop, while the Left motor is moving at full power, causing the robot to turn right, thus heading towards the Black line.

When the Light sensor is above the Black area (dotted line C), the Left motor will stop, while the Right motor is moving at full power, causing the robot to turn left, thus heading towards the White area.

As you can see, since the graph is linear, the robot should automatically correct itself till it is moving along on its equilibrium (dotted line B), as you can see in the video attached above.

Line Follower - Bit Logic Method

I have been tasked to teach one of the most fundamental programming ideas, Line Follower.

Before we begin, we should understand what Line Follower algorithm there is, and what is the best and quickest method. So today we will explore the easiest one of them all, the 2 bit line follower algorithm.

View the image above, the Black Box represents an enlarged Black line, while the tiny Red line represents where the light sensor is on and what it will see. You will notice from the video above, you will notice that the NXT Mindstorms actually makes very tiny zig-zag along the black line. If you look closely, it is actually like the red line above.

The idea is simple, if the sensor is over White (Point 1), you turn right towards the Black area. When you are over the Black (Point 2), you turn left towards the White area. Effectively you are hugging the left edge of the Black line.

Using just the a simple Switch Block, and 2 Move Blocks, we are able to program the bit logic line follower, as explained in the previous paragraph.

Being the easiest line follower algorithm to understand and teach doesn't make it the fastest. It only manage to complete the track in about 2 minutes, which is extremely slow!

NXT Adapter is here, FINALLY !

Hi people, I know it's been "a while" since I last posted about the NXT adapter prototype, but the NXT Adapter is finally out now, phew....so without further adieu, let's look at the real thing now :)
TaDaa !! This is what it looks like in our current version, the PCB (Printed Circuit Board) together with the transformer...
Here's a close up shot of the PCB together with other electronic components & the adapter jack.
Here's another close up shot of the PCB from a different angle. The metal cover is securely attached below the PCB & is painted in grey colour to match the colour of the NXT itself.This is how it looks like when attached to the NXT controller. The metal cover will hold on tightly to the NXT controller through friction once it is firmly pressed onto the NXT controller.
Here's a picture showing the comparison between the normal plastic cover vs. the metal cover.
Now, for those of you who have no idea why we took the trouble to come up with something like this, let me recap why would you need the NXT adapter :

• You see a hole in your pocket after spending too much money changing normal batteries.
• You woke up in the morning next to your NXT realizing you fell asleep yesterday while waiting 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. Since acceleration is inversely proportional to mass, less mass means your robot can accelerate faster with the same amount of force applied. You get my point now ? :P
• So we can make some money too by selling you the adapter hahaha...

If you are interested to get one (or more), you may reach me at yipyaukean@gmail.com

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 =)

Vertical Limit concept bot

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

Concept

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.

Motors

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.

Sensors

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.

Programming

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 (^_^)

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...

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

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!

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)

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)

FLL 2009/2010

First Lego League holds a competition yearly, with the same question being used for the whole world. What I love about the FLL is that, everyone competes using the same questions, same play field, as well as same lego sets. Where all remains the same, only their creativity/ingenuity of each team to solve the problem will make them the winning team!

You can view the full FLL rules for FLL Smart Move 2009/2010 here.

For a quick summary of what you will expect from the FLL Smart Move 2009/2010, you can view the video below

I suck at writing blog.
But still, here's my point of view on the robots.

Small and agile with risks are what our competitors did during the K. Terengganu NRC.
They used the aim and shoot method.
This method basically is to make the robot move straight and grab ( other methods also apply) the object and put it to the destination.
They risk:

1. The position of the robot at start point must be EXACTLY where they have programmed.
2. Battery voltage must be EXACTLY the same as what they have programmed using.
   
3. Luck. No luck = GG
4. They must programmed it correctly in a sense that the programming must be accurate by the millimeter. And that's just too back-breaking for us?
5. Even the condition of the mat will AFFECT the performance AKA determine their fate.
   

THE SLIGHTEST MISCALCULATION, MISTAKES, EVEN BY A MM, WILL RESULT IN FAILURE.




But if, and if, they are:

1. Lucky
2. Able to program well
3. Makes no mistake.

They get lots of points as their robot is fast.


Next, is what we did.

Use Light Sensors to move with the black lines on the mat.

This method is:

1. More accurate.
2. May auto-recover.
3. Minimises human-error as the robot will move itself without requiring us to aim the robot.
4. It's now a fully-automated robot. No a car that picks up objects blindly.
   

Nothing is perfect. Same goes with this method.

It's :

1. SLOWER if compared with aim and shoot method. But if it's programmed well it may go faster ? ( unconfirmed, no chance for us to see others use this method )

Method of getting object.

This is gives us a headache till the very end of the competition.
We thought of all kinds of methods. Some fail. Some shines.
At last, we decided to go with the box method.
The robot's arm is a square that extends out of the robot.

The arm

We got frustrated thinking of other methods that we go ahead with a very straight forward box that just swoops in the object.

Well, this method brings a lot of problem.
Especially with the rubber object.
Rubber + mat = Friction and loads of it.

With the robot pulling the object, it's like telling it a mammoth task for the robot. It squeaks, jerks and even jumped over the object with the object still stationary.


There's also the grab method, grab-n-lift method, scoop method and so on.




It's late now. gtg. So, anything missing? Wrong? Bullshits? Please dump it in the comments.
And hopefully, I'll make up to it in my next post.




P.S. This is my first time writing and posting a blog post.

Point of View: Robot Massacre

Hello world ! This is my first post. Thanks to Eric for the invitation.
To make sure our robot will keep moving forward, I came up with these few questions and opinions that I believe is essential for our future robot construction.

First of all, the size of the robot. Our previous robot moves slow and steady although a bit bulky.
The mass of our previous robot is a pro and also a con. The weight is important to decide because it will eventually affect our turning, movements, power consumptions and of course the type/number of wheels. How can we give a balance "diet" for our future robot from being fat and slow? We can build it small and compact, mild and light or just with simple mechanisms.

I believe the robot should be small, simple and not-too-light.
Small, it is easier to build and does not interfere with the tracks or turnings.
Simple, just in case anything screws up, rebuilding it would be easier.
Not too light, a little bit of weight is recommended to prevent the robot from slipping, jerking and possibly gets off track.

Another thing to take note of is the sensors. It is always light sensors. Our previous robot is causing a lot of inaccuracy and failures on turning.
The obvious reason is the distance between the sensors and the wheels. The sensors shouldn't be too far from the wheels nor too close.
Our future robot should have a close enough distance from the wheels. So when the robot stops, the wheels are in the exact location as we want.

Arm mechanism. So called the pain in the ass.
Is there an arm design that could pick up almost every shape and sizes ?

Is grab-n-lift a good option ?
Do we really need an arm (guess so) ?

The following is the battery. Which battery should we use on competition day, rechargeable or new AA batteries? It would be best if we get some sponsorship from the school for batteries. Program using rechargeable then optimize it to a higher voltage, sounds good ? I believe the old design is a power hogging machine, therefore the new design must be small. It failed on the design and programming. Better design is a must. Until now, I'm still wondering how did we won third prize in the competition with this rotund golem.

Next, the wheels. Should we consider more than 2 wheels ? Do we need small wheels or big wheels? I think we are better off with big wheels (previous wheels).
The small wheels isn't giving much "grip" from what i see, and it may slip if we use a faster speed, it's just too light. The wheels are depending on the size of our robot. It's not like we put tiny wheels on a giant machine, that would be LOL !
Besides that, if possible, we're going for max power and max velocity. We never know what would happen next.

My views may be a little bit of obscure and ridiculous, I think you get the idea. Well, it's just my point of view.

Tell us what do you think about a winning robot.

Cheers.
-CH-

3D modelling using Solidworks

I have been relearning Solidworks (a 3D CAD software widely used by engineers & designers) for a while and decided to do some simple modelling on my own after going through some of the tutorials. So i just picked the Technic studless straight beams as my subject due to its simplicity & my skill level :p

In engineering, just like in real life, there are many ways to solve a given problem and the rule of thumb is always to solve it using the simplest method. I completed the first 3M studless straight beam using 7 steps (or 7 features),

But i thought i used too many steps to complete the model, so i made another attempt to remodel the beam using different methods and this time around it only uses 3 steps to complete the model.

Satisfied, i continued to model the rest of the straight beams of varying lengths including 5m, 7m, 9m, 11m, 13m, and 15m & made a screen shot of all the different beams lined up together,



Overall, i had a fun experience using Solidworks to model the Technic beams. I understand there are a lot of LEGO CAD softwares out there that would satisfy most Mindstorms & Technic fans, but for the few who find them too limiting in features, eg designing your own custom parts, performing some stress analysis, or some motion analysis, then you should give Solidworks a try ! (provided money is not an issue for you :p)

Quick engage/disengage mechanism for gear trains

Due to the challenging design of this year's Robot Energizing objects, many teams have come up with pretty interesting designs to carry the resources (i.e coal, bio-fuel, and esp. solar). One of the biggest challenge the teams face is to design some mechanism which can grab and lift the object by using only 1 motor as the other 2 have been used up for navigation.

So, some of the more successful teams have employed the grab & lift mechanism similar to the one shown below,

This is a brilliant solution for grabbing & lifting the Solar rescource off the ground, but there's a slight drawback to this design when the gear reduction ratio is too big - you need to turn the motor many rotations to reset it to the original position everytime the robot misses. So one the solution the teams come up with is to attach another knob/wheel along the driving axle for manual reset. However, this still takes up an awful amount of time, especially if your robot miss more than once :S

Recently i came across a very interesting mechanism that can engage/disengage a gear train with relative ease and i thought it would be an useful add-on to the grab & lift mechanism for quick engage/disengage in the event the robot misses the object.

I have uploaded the videos showing how the quick engage/disengage mechanism work along with the grab & lift mechanism without the quick engage/disengage mechanism for comparison.

Grab & lift with quick engage/disengage

Grab & lift without quick engage/disengage

This mechanism can even be applied to grabbers which uses wormscrews, which can save even more time on resetting the grabber.

Almost Famous - NRC 2009 Newspaper Article

I have been in Kuala Terengganu for less than 6 months, and I am already making a scene. Creating too much publicity is NOT a good thing :)

We had a little tiny article printed on the Sin Chiew 18 July 2009 about our recent win in the NRC 2009.

Since I cant read chinese, I can't give you a summary on what it says, but most probably only good things :)

Those who didn't see the article in their Sin Chiew is because it is printed in their equivalent of Metro section (The Star), where it only talks about local events in Kelantan, KT and Kuantan (East Coast).

Lego Technics Quad Bike 8262

Isn't the Quad Bike just sexy? I must admit, most of the 2009 Lego Technic models are just awesome. In fact, I am eyeing the Technic Go Kart too! Not forgetting all the Star War Series, that I have already spent too much collecting.

I must admit, but this is the second Technic set that I have built. It is NOT that I don't own any other Technic sets, but all of is still Brand New in Box. I have the Lego Bulldozer 8275, but just haven't gone around to building it. I am sure it is an awesome set, with all the PF Motors!!

When I first opened the box to the Quad Bike, I realised that there is so little pieces in there. With all the packets on the table, I was wondering whether have they left any parts out? Most of the weight of the items are in the rubber wheels :p

After pouring all the parts out on the table, I realised that it is filled with many many small parts. After a quick flip through of the intruction booklet, I realised that there is alot of little details (and little parts) used to make the quad bike.

I spent closed to 2 hours building the Quad Bike. I really like the front suspension that the Quad Bike have. The design is great, and I hope to incorporate it in my future NXT designs. The only problem is that, the pieces and absorber piece is unique to this set, and NOT included in any standard NXT Set :(

It has an alternate building instruction to build a Buggy. I will be building it soon, and will definately post the pictures of that soon.

NRC 2009 - 3rd Place Kuala Terengganu State

Here is a photo of the kids from SMK Chung Hwa Wei Sin with the 3rd Price win at the NRC 2009 Kuala Terengganu State level.

Congratulations to them on work well done of getting 3rd place. It is their first year with the NXT and coaching them from ground up is no easy task, not to mentioned with their busy schedules, they only had about a month to come up with their robot design and program for it.

Going against students who have got NXT experience, not to mentioned that they had already completed a similar NRC 2008 question is no easy task. Luckily with the long hours put in, they manage to obtain 3rd Place.

The kids are (from left to right)

• Cedric
  
• Koong (Chief Programmer)
  
• Chen Hui (Chief Builder)
• Eric Tan (Coach)

I expect nothing less from them next year, only First place would be acceptable!

I will be posting more on my NRC experience in the future post, as well as the design concept of our NRC 2009 robot, as well as mistakes that we had made.

Lego City Coat Rack

Look what we have here. It is a very similar concept to what was posted earlier. Check photo below, and link to posts.

Automatic Bucket Filler

It's been a while since my last NXT project, and since i got a week off for CNY so why not do some home improvement to make the home a better place to live in, right ?

In the house i live in, "someone" just have a strange habit where they like to leave the tap dripping all the time and i can never understand the logic or the rationale behind it. So i decided to probe deeper and find out the answer - "Oh, i just leave it dripping all the time so it will fill up the bucket automatically" was the reply i got :S

The problem was the bucket overflows all the time that is a tremendous waste of H2O...Hence, i came up with the Automatic Bucket Filler.

This system consists of one motor and one touch sensor. When the water level is low, the ball drops to a lower level and the touch sensor is released, signalling the NXT to rotate the motor to turn on the tap; when the water level is high, the ball raises due to buoyancy and presses the touch sensor, signalling the NXT to turn off the tap.

The motor turns the tap.

The ball rises and lowers depending on the level of the water, and when the level is high enough the ball will press on the touch sensor to signal the NXT to turn off the tap.

Ok, i know you can't wait to ask me how much can i save with this system and what's the ROI ? After doing some simple calculations,

Annual savings on water bill : RM 5

Cost of Mindstorms NXT      : RM 1400

Return on investment (ROI): RM 1400/RM 5 = 280 years !

Hey, just 280 years only mah, not bad wat... after 280 years can start saving RM 5 every year oredi, so chun !

Lego USB Drive - Thinnest Ever!

I am sorry if this is a little off topic. I made a few over the weekend. I reckon you can't get smaller than this for a USB Flash drive. If you guys would like one, drop me a message. The best thing is that, it is Vista ReadyBoost compatible!




The LEGO USB Drive featured is almost completed. I have not mounted a small ring that would allow the LEGO USB Drive to be mounted either on a Keychain or a Lanyard (perfect for showing off!)

Currently I have 6 colours available

I would like to apologise for my sub-standard photos. Photos would be re-taken with better lighting condition and using a tripod to ensure that the photos are sharp as it can be!

You can check out more details here.

Simple Skid-Steer 4WD with Power Functions

Over the weekend i just wanted to build something out of the new power functions elements from the 8275 Bulldozer - hence i came up with this simple remote-controlled model with no programming but pure fun.

This is a simple skid-steer 4WD using power functions elements including 2 XL motors, 1 battery box, 1 receiver and it can be built in under 5 minutes.

Each side of the wheels is controlled by 1 XL motor and steering is accomplished by turning both motors in opposite directions, just like the way you drive a tank...

The car tends to jerk a lot while turning due to the nature of skid-steer architecture but i had a lot of fun with it, especially with the reaction i get from my sister's dog when i drive this thing around right in front of her ^_^