Not-so super Lego Technic car, what I’ve learned so far

And so my endeavor with Lego Technic continues. Still wanting to fulfill my childhood dream of building a Lego Technic car, I’ve started buying parts from BrickLink. My goal is quite straight forward; build a car with these simple specific mechanical functions:

• Independent suspension (who doesn’t want this?)
• All wheel/four wheel drive
• Real working steering wheel mechanism

I had a fourth requirement; all wheel steering, but decided to cancel it off for now. And that’s it, simple.

I later added one other thing; Power Functions.

By the way, the last time I played with Lego, there was no such thing as studless Technic bricks. But it didn’t take me long to get familiar with it. I have to say, the studless system has its limitation but the advantage is far greater, the best being everything is simply multiple of 1 unit.

Anyway, coming back to my effort, here’s a picture of my first attempt at building a car:



Overall, it’s very flaky. The only part of the car that is good is the rear as I spent days working on it. The mid and front part, took me only half a day because I was so eager to get this thing moving. And it did. Well, partially anyway. As you can see on the top right of the photo, the Power Functions’ battery pack is on and I have one XL motor in it, so this baby can move, but only forward and backward because, if you look closely, the steering is not done yet.

Here’s a few more photos:

The rear part. I took some effort in ensuring all the Power Function parts are easily removable. Interestingly, the battery pack becomes the car’s structure, forming a rigid part for the suspension to press on to.	One XL motor is marginally enough for this model. I have to get another XL motor.
This is actually a top view of my car. Clearly very empty. It looks like the undercarriage of the car.

So, what have I learned so far?

1. If you have a heavy model, don’t use bevel gears in perpendicular setup to transfer power from motor to gear box. If you do, at least make sure if you have enough counter gears, because under high stress, the driver gear will jump a tooth or two before the follower follows. The better option is to use knob wheels.

No.	Yes.

2. More gears is better. Yes, more gears will introduce more friction and as such will lose efficiency, but what I've found, using more gears will provide higher durability and add some needed sturdiness. Example shown below. Originally, the drive shaft connects directly to the input gear of the differential via a universal joint. Simple, yes. Durable, not. In the setup shown below, redundant gearsets are used and I've found them to be much better and more reliable at transferring power to the differentials.



3. Use shorter shafts where ever possible. Lego, as you might have been aware, are made of plastic. So, the longer axles are somewhat prone to torsion effect. Another way to counter torsion effect is to again use redundant gearsets that are spread apart along the axle.

After a ‘successful’ run, I have taken my model apart to fix known issues, and hopefully, the second version will be much better. I’ll report back soon.

-Wan Khairil Reza-

Lego Technic 9392 Quad Bike Review (and Mod)

If you've read my previous post, I've recently made it back to world of Lego. My first come-back set is the 2012 Lego Technic quad bike (9392).

Pic 1: Lego Technic 9392 Quad Bike

It is a decent Lego Technic model. Building it was without any problem. I didn't time myself, but I'm sure it was less than 10 minutes.

Overall, I like it. It captures the essence of a quad bike. The big wheels, the body panels, the bouncy high suspensions and this model even has a chain linking the dummy engine to the rear axle. What I love the most is the front suspension; good travel and works nicely.

But one thing that I'd rate poor is the steering. It is loose with lots of free play and is not center balanced. Makes it hard for the quad bike to stay straight. This is due to so many loose joints in the steering design.

 
Pic 2: Loose joints that contributed to lousy steering

Another thing that I consider a design mistake in this model is the location of the swingarm’s pivot axis, which affects the tension of the chain. In real world situation, a chain's tension is kept constant by ensuring that the distance between the drive sprocket and the wheel sprocket is kept constant. Otherwise, it might cause the chain to become loose or break. To achieve this, the drive sprocket must be on the same pivot axis as the swingarm. But this is not the case for Lego Technic 9393 quad bike. Pic 3 shows the location of the drive sprocket axle and the swingarm pivot point.

Pic 3: Default 9392 Swingarm setup

Pic 4 and Pic 5 show that the chain becomes loose when the rear suspension of the quad bike is pressed.

Pic 4: Chain in normal condition	Pic 5: Chain becomes loose wen rear is pressed

I have to solve this two issues.

First, the swingarm. I modified it so it pivots at the same axis the drive sprocket. I added or removed as few pieces as I could and I reused as much as possible. Pic 6 shows the moded design. And as can be seen in Pic 7 and Pic 8, the chain's tension is maintained when the rear suspension is pressed. Success.

Pic 5: The redesigned swingarm

Pic 7: Chain in normal condition	Pic 8: Chain doesn’t become loose when rear is pressed

Next, the steering. I noticed the toe of the front wheels are going slightly outwards and it gets worse when you push the bike forward. I used this to my advantage. What I did was I flipped the whole front part of the quad bike, as shown in Pic 10. By doing this, I turned the toe inwards. The steering arm is also now at the back.

Pic 9: The original steering design	Pic 10: The modified steering design

Pic 11: The original steering design, with outward toe	Pic 12:The moded steering design, with inward toe

The inward toe actually straightens when pushed forward and does make the bike go in a straight line! Nice. to finish off the steering, I also used a universal link to give the handle bar a slight angle. Success.

Pic 13: Universal link on the steering

The moded final model is much better. I wonder if I can motorize this with a Power Function.

Pic 14: My version of Lego Technic 9392

Wan Khairil Reza

My first two-speed (then four) Lego Technic gearbox design

Last weekend I took to myself to design my very first Lego Technic gearbox. I set a simple goal; a two-speed gearbox with 1 input axle, 1 output axle, and no gear grinding allowed.

I'm still at the very early stage engaging in this Lego Technic hobby and I'm only beginning collecting my Technic parts. As such, unfortunately, I don’t have enough parts available to build an actual Technic gearbox. Luckily, Lego provides a useful tool to help people virtually design their Lego projects. It is the Lego Digital Designer (LDD) and it is downloadable totally free from Lego's website. Even though LDD is not as flexible as I wish it could be but it is good enough for most design tasks. The learning curve is not steep, provided you have some foundation in Lego building. Good mouse dexterity would come in handy as well.

In this blog post I want to share my process in designing my gearbox, using LDD for now and hopefully with actual Lego Technic parts soon.

First, being a newbie, I figure I need to study Lego gear pairing. The screenshot below shows what I did in LDD. The objective here is simple; to see how various pair of gears can be positioned, since Lego designing is generally constrained by the number and position of the studs and holes of Lego bricks. So, I tried out a few combinations and roughly got the idea. I also found the site that helps in Lego Technic gear pairing.

Pic 1: Gear pairing exercise

 

Next step, I went straight to designing my gearbox. By the way, if you need to understand how gearboxes work, refer to How Stuff Works or here for Lego gears tutorial.

The screenshot in Pic 2 below shows what I did. I decided to lay it flat first, in order to see how the gears would be arranged and linked. As I've mentioned, I don't want gear grinding during shifting, so I use the driving ring that allows me to lock on to either one of the free wheeling gears.

Pic 2: The gearbox, flat

Basically, the gearbox provides a gear down from a 12 teeth gear to a 20 teeth gear (1:667) shown with green gears and a gear up from 20 teeth to 12 teeth gear (1:0.599) shown with grey gears. Because my design is laid flat, with very little effort you can trace the gear and axle movement of each speed setting, as shown in Pic 3.

Pic 3: Gear one and gear two

Now I know what I needed, next would be to simplify the design. Just like most things in engineering or computer programming, some components can be reduce, reuse or shared. After a bit of fiddling, I got this:

Pic 4: My two-speed gearbox

Pic 5: My two-speed gearbox, bottom view

Simply, the flat gearbox is ‘folded’ so that the gears and axles are layered. I've also combined the output axle, and made it compact. And just like that, I've completed my task. I’ve designed a two-speed gearbox. I can now go and watch The Big Bang Theory.

But I didn't.

This is too simple and too easy. I also looked at my gear ratios and it was clearly unrealistic.

If I can make a two-speed gearbox, surely I can make a four-speed version. The simplest thing to do is just to replicate my two-speed gearbox, and change the gear pairing to have different ratios. And that's exactly what I did.

Pic 6: Two two-speed gearbox

Now, the available gear ratios are:

1st gear 1:3
2nd gear 1:1.667
3rd gear 1:1
4th gear 1:0.599

But by having two two-speed gearbox, I now have two input and two output axle. So, the simplification cycle starts again. With a little rearrangement, and a few extra gears, Pic 7 is what I got:

Pic 7: Final four-speed gearbox

The final design fulfills all my requirement. It's a 4 speed, 1 input, 1 output, absolutely no grinding while changing gears. Can’t wait for my Lego Technic parts to arrive!

Am I done? Yes for now, but I can see a lot of gaps in my design. I'm sure seasoned Lego Technic designers would take one look at this, smirk and point out what I should have done. And I hope they do, so please, share your thoughts.

- Wan Khairil Reza -

Reignited love (and hope) for Lego

Having a child of your own will open up new life changing experiences and might also rekindle some of your childhood interest. Now, having 4 boys will put this so called experience into overdrive. One thing that got reignited (extremely) for me was my love for Lego.

Very brief personal history; My brother and I had a decent amount of Lego when we were kids. Mostly the normal Lego bricks. I can still recall most models when visiting the Brickset website. The grandest thing I had was a Lego space solar transporter (6952), which dad bought when I was 9. And also one (yes, one) Technic set, a roadster (8832). Then, I grew up and all was gone; literally. Gone because dad decided throw (mom said he gave it) away my old toys as it was taking up space and I wasn't living there since I was 13. I'm not angry at all at my dad, though I wish he had done otherwise. But it IS his house and it was his money that bought all those Lego. And just like that, Lego was nothing more that a childhood memory.

Fast forward to the future.

On my eldest son's first birthday back in 2005, his grandmother (my mom), bought him a box of Duplo. He immediately loved it. From then on, his (or should I say, our) Lego collection grew and grew. From Duplo to Lego bricks to Lego theme sets. As my children's interest grew, so did mine. Add to that the easy and friendly Lego website plus fan sites such as Brickset and YouTube videos that gave access to more information and introduce other Lego fans. And now, in less than a month, Legoland Malaysia will open its doors and it's only about 20 minutes away from our house!

All these have put my love and interest back in Lego.

As a toy, Lego is a toy that can give you other toys. Want a robot? A car? Voltron? A dagger? Your own town? You can just make one for yourself, by yourself.

But Lego is also more than a toy. It's a tool for learning. A tool for turning imagination into reality. It can be art. And yes, you can even collect the rare ones for trading if you like.

And this is something I wish and hope that more of my fellow Malaysians will see, realize and embrace. With the opening of Legoland Malaysia, I hope the younger people will be encouraged to delve into the world of Lego and allow their creative mind to grow and develop further. Even though Lego are relatively expansive, you do get high quality products and an extremely cohesive eco-system, which means you can re-use your Lego from the past and into the future. Consider it an investment.

From the simple toddler friendly Duplo to Lego bricks to the more sophisticated engineering-ish Technic, Lego offers a lot in developing creative mind.

Here's my wish list for Lego in Malaysia:

1) To have local Lego workshops and exhibitions

2) A more active and involve local Lego fan club

3) Get schools to have Lego competitions, activities or even some sort of Lego Day

These can be done and I hope I can be part of it.

Ride the Wave

It actually came. About a month ago, I got my very own Google Wave invitation. I was somewhat excited. Sign up was super easy as I already have a Google account. Actually, in my case, it was an activation rather than a sign-up.

So there it was. Google Wave. I looked at it, and honestly, I have no freaking idea what to do next! No wonder this site exists.

Fortunately, I know where to get some help. If you have been listening to This Week in Google podcast, you would know too. Complete Wave Guide by Gina Trapani. By the way, if you haven't listen to this podcast, you should.

So, after reading through the guide, here’s the very key concept of Wave:

• Wave is a new take in communication; real time, archive-able, multi-edit. It even requires its own infrastructure.
• It is not to replace email, but to take on one of the thing that people have (mis)used email for; collaboration.

I now know what to do. Then, my next problem came. I have no one to Wave with. I nominated some friends, and 2 of them have joined, but that didn’t help us at all. We quickly realize the reason why we are not able to use Wave. We don’t have anything to collaborate on.

So here’s what I have to say about Google Wave; It is cool and useful tool if you have a use for it. Right now, it’s more a solution looking for a problem. And honestly, I have never had the problem it is trying to solve.

2010 - Tech Prediction

I’m joining the pundits. Here are my tech related predictions for 2010.

1. Apple will conquer a new market segment

Be it an iPad, subscription music, tv, ebook reader or something totally new, Apple will be conquering a new market segment in 2010. And everyone will once again come out and go "why didn't I think of that". The rest will change their game try to catch up.

2. Local/cloud combo apps will reach mainstream

I believe the "cloud computing" hype will tone down this year. What more and more people will realize, is that the best experience and approach is to have a good mixture of both local and cloud services. I recently started to use Evernote and I'm glad they have a locally installed version of the software as well as a good web-app. And I believe in 2010, more mainstream software will provide local + cloud solution.

3. The players will realize that the 'apps store' is only for Apple(‘s business model)

Apple's apps store for the iPhone and iPod Touch works mainly because the platform is closed. The number of hardware that developers have to take into consideration for the Apple App Store is extremely finite. Meanwhile, the competitors have no easy way of doing it, because of the vast versions and types of hardware that they make. Take Nokia for example. There are all sorts of screen size and hardware capability in their product range, event within the high end N or E series. As a result, the Nokia Ovi store is full of nothing for most people. Someone needs to fine a better approach. Otherwise, the Ovi Store or Android Market will just be irrelevant.

4. Google OS will get lukewarm acceptation by the public (non-tech people)

It’s another version of Linux. How dramatic can it be? Even on netbooks, most non-tech users will still want to use Windows. Not this year.

5. The one prominent (quasi-standard) video format will prevail

I honestly think (and hope) that this year, we will see a video format that will prevail as the de-facto video format for consumer, just like mp3 has become for audio.

6. Microsoft will actually become more prominent on the web front

This is the year, we will see Microsoft becoming more active on the web apps/services front if they want to stay competitive and relevant. I think Microsoft has been too quiet for too long.

7. Location based/aware services will see dramatic increase

The advancement in mobile computing technology and the ever expanding roll out of high speed wireless internet will create the demand for location based services. In fact, real time location base services might start to come out this year. We might see it during the FIFA World Cup in South Africa this year, where visitors to the match venue cities will create a demand for such services. Also, through in the social networking angle in there.

8. Normal phones and smartphones will be less distinguished

The line separating normal phones and smartphones will get very blurry this year. More mainstream phones will have features that are currently associated to smartphones. GPS, highspeed internet technology, email, social-network capability and video are features that will become a norm, in as least the middle level category of phones.

Noisy Social Networking

Last Friday, 22 Oct 2009, Facebook made another user interface change. This made me realize what is wrong and has always been wrong with a lot of social networking sites. It boils down to the signal-to-noise ratio.

I joined Facebook back in 2007 but after only 2 months, I deactivated my account. Why? Because the noise coming from Facebook is unbearable. The value of social networking was drowned by all the unnecessary news that Facebook kept shoving into my face. Not to mention the millions of apps that throngs my friends’ pages which made the site slow and meaningless.

Then, 3 months ago, I reactivated my account after seeing that they had (arguably) improved the look and feel of the site. This time round, things are slightly manageable and I find Facebook useful to a certain degree.

However, last Friday’s user interface change made the noise getting louder.

What Facebook did this is; they believed that everyone really really wants to know what all their friends/networks are up to, so, everything is now shown in the so called Live Feed. And, Facebook figures out some of those posting are worthy of a news status, so they are pinned in the News Feed.

First of all, no. I don’t go to Facebook to get the news. I go to news website to get news. And no, I don’t freaking care about who’s befriending who. All these are just useless information clogging up my bandwidth. And now there is also this “Leave a comment on this guy’s wall” or “Help this guy find more friend”. Really? That is so… cheap.

Here’s what I really want from Facebook, and perhaps other social networking sites too, is customize my feed. Let users choose what kind of updates they get and from whom should be highlighted. Leave the all activities feed there so maybe once a while I could look into it if I want to.

I'm thinking of abandoning Facebook. I've done it before.

The Browser Verdict

My verdict is in. Google Chrome is my browser of choice.

After installing it in back August, I find that I use it more and more, and today, I’d say 80% of browsing is done in Google Chrome.

The thing that sealed the deal; it's snappy. The app launch fast and renders pages fast. So far, Chrome has not crashed on me and I have version to date (3.0.195.27).

I still miss the address bar dropdown button though, and I’m not alone. There’s a Google Chrome forum for it. I have more than 8 sites that visit daily, so please Google, just give me the dropdown button.

Another thing that I’m not too fond is Chrome breaks the Windows interface. It doesn’t have a title bar when the window is maximize. Small price to pay for a bit more screen real estate, especially on the widescreen notebook.

As for the other browsers that I have, I still use IE every now and then. In fact, it is still my system's default browser. Honestly, there’s nothing to hate about IE. Since I cannot remove it from the OS, might as well use it every now and then.

Firefox on the other hand, has fallen from grace. Compared to Chrome, Firefox is sluggish. Especially with all the add-ons I've installed. I only use it if I need to get some Youtube videos locally and also the portable version. By the way, I no longer use Firefox in Ubuntu because I've removed Ubuntu! (Another story for another day).

There are news saying that add-ons are coming to Chrome. I hope it will not degrade the browser like what has happened to Firefox.

With the emergence on Chrome, I’m sure the people at Microsoft and Mozilla will come out with something new for their browsers, meaning, even more choices for the users.

I also doubt we far from when browser is just a browser; not until there’s a major paradigm shift in the desktop OS world.

Until then, I’d recommend everyone to install and use Google Chrome, if you haven’t done so.

Another Browser, Another Choice

OK, I'm impress. Google Chrome is fast. Now, let's see.....

I use IE because, well, I just do. Ever since IE 2.0. And IE 8 is actually a good web browser. I can't point to any outstanding feature but what it does, it does well. One thing I do want is a download manager. In terms of page viewing, I haven't found one that doesn't work.

I use Firefox, for a few reason; it's the default in Ubuntu, has portable version and very very customizable. But the latter seems to also be its undoing. I've found out that the more extension you install, the bloater, slower and unreliable Firefox gets. The other major annoyance with Firefox is the need to restart after every single update, be it the browser or the extensions. In its default form, Firefox works fine. In terms of page viewing, I don't find any difference with IE. I also love the so-called Awesome bar, ie, the address bar. It makes sense to have my mostly visited address pinned and sorted according to visit frequency.

For the record, I did have Opera on my system, and I have install/uninstall it a few times. It's an OK browser. One thing that bugs me about Opera (and we're talking about version 9 something here), it has this quirk in rendering images, where, if the image is not fully loaded, it will redraw (and you can see it) every time you scroll or switch tabs. Page view is fine. No extension as far as I'm aware. I can't put my finger on it, but there's something wrong with Opera. I just don't know what.

And now, I have Chrome. The sparse bare minimum user interface is so Google. I love the single address-cum-search input bar. It's very easy and intuitive. Actually both IE and Firefox can search from the address bar, but they provide a dedicated search input bar by default, which gives an impression that address and search don't mix. But with the current version (2.0.172.39), Chrome's address bar is missing something major to me; it doesn't have a drop down button! I don't get it. But I do like the tab handling. Dragging a tab out to open a new window is quite useful. I do wish they have IE’s colored tabs feature to show related tabs.

So now I ponder, do I really need another browser? Should I squeeze Chrome into my life? Maybe drop Firefox?

I do use a some Google services like Gmail, Docs and Blogger. Maybe these services work better in Chrome. I don't know, but that seems to be what I'm planning to do; use Google stuff on Chrome and see if there's anything extra I get from it. I'll report back after a few weeks.