dinsdag 16 augustus 2011

The smoby trike adventure part 2 – Finding the solution

In my last post on the smoby trike I bought for my son, I shared what horribly loud it was and what to do with it. It also talked about finding the root cause of the noise and what to do about it. The main noise factors are indeed the bucket and the wheels. So how do we get the noise down? Well let’s put our thinking caps on first: Sound, what is sound? Vibrations in the air. Our ears pick these up and they turn it into a signal that our brain recognizes as sounds. To put it simple:
Air (vibration) –> Ears –> Bain (Sound)
So these are our options, we can tweak our ears, our brain or the air. Sounds tempting to do something about our brain doesn’t it :)? But to do something about the vibrating air before it reaches our ears and is the more pragmatic and practical goal for some household hacking on the trike.
Let’s use another tool to generate some ideas about reducing the noise. It’s called a morphological scheme. Here’s how it works: you take a goal (make air vibrate less) and doodle what could help reach that goal with no concern for reality or feasibility. Here’s mine:
morphological scheme smoby trike
Now this is just to get the creative juices running to see broaden your scope. I can imagine my handwriting being illegible on the picture so here’s what I thought of: foam , tape, clay, noise cancellation, wheels, skids, box.
Now we have multiple solutions and tighten our scope and start to define our limits. For example
1. Price - Under 10 euro solution
2. Effect – It has to work
3. Endurance – has to withstand daily use

The solution?

Noise cancelation would be a cool idea to experiment with, you know add speakers in the wheels that try to cancel out the sound waves that are being generated. But alas to expensive/time consuming. Building a noise isolating box around the tricycle would work but make the trike rather unusable. And spraying foam around the wheels would help just until the wheels have turned one circle, and all the foam is left on the road, I think the same goes for clay. Changing the current wheels with skids or another will increase the complexity and cost. So I’m left with… Tape. The wrap up will be in a next post.

vrijdag 12 augustus 2011

My personal acoustic guitar buying guide, Introduction


I recently purchased my third guitar over a time period of 7 years.
Guitars 400px
I started out with a classical nylon stringed Yamaha c-70 I got for my birthday. This got me learning guitar, thank you yamaha. After 4 years I switched over to a steel string Epiphone EJ-200 super Jumbo model. I just loved the sound and the looks. Getting the EJ really improved my playing because every song I played sounded new to my ears compared to my old guitar. After another 3 years it was time for a new guitar. Although I loved me EJ and I got attached to it, the sound couldn’t compare with an all solid guitar and because I could get a good price for it… I traded it in for an Eastman AC320CE which is a dreadnaught model. It did not have the flair of the EJ and I don’t like the looks of a dreadnaught much, but the sound was unbeatable. And that is first and most important thing about buying a guitar. Use your ears, they don’t lie and only they can tell you what the best sound for you is. And what is the point in buying an instrument that you don’t like the sound of?
I’ll end this section with a quote from Justin referring to scales over at justinguitar.com (amazing site by the way!):
If it sounds good, it is good
If it sounds bad, it is bad

The pointers

1. Use your ears
Your ears are two very complex high quality receivers. They will tell you more than a brand or price tag. Before I bought my EJ all guitars would tend to sound alike. So I went to the store multiple times and let my ears get used to the different sounds that guitars have. And by doing that I developed a liking for certain sounds and without a doubt the EJ-200 had the right sound for the right price for me.
That’s it for now. In my next post I’ll be looking into form factor and woods

woensdag 10 augustus 2011

The speed of sound on the dell E5410

I'm amazed.

Here I am with my Dell Latitude E5410 laptop with an intel i5 processor and 4 gigs of ram running windows 7. And here comes the amazing part, Windows Media player/Itunes has a hard time playing mp3's fluently. Almost at random it stutters in playback and this off course really annoying. Almost random because it does sometimes seem to correlate with dragging your windows across the screen. But still with a wopping duo-2.5 ghz at your disposal I'd think the CPU should be able to handle this...

A work around that has some succes is to increase the cpu priority setting in the taskmanager manually to realtime. This is less than ideal since you have to do this everytime you restart the program. See screenshot: image

Any thoughts anyone?

zaterdag 7 mei 2011

The smoby be fun trike review

We just bought a cool tricycle for Timothy, a Smoby - "be fun trike" (what kind of name is that?).He loves it and is happy with it, check out the how he even bought flowers for mommy on his second ride, awwww. 

Anyway cool features why we bought it:
  • Lockable front wheel 
  • Pedals can turn freely or power the front wheel 
  • A push bar 
  • Adjustable seating 
  • Price :) about 30 eur

What did you say?
So far the good stuff, now comes one of the major cons... it noisy! Using my highly effective and trustworthy iPhone decibell app it maxed out at 84 dB and on average it was around 80 dB. To put it in perspective, sitting in a room quietly listening to music is around 55 dB. Ok so maybe that's not the best example since one person's quiet music is not the other. Well according to this website: noisy website, it's about the noise level of a diesel train traveling 60 km/h at a 30 meter distance. Now that's usually no problems outdoors, but you do get a lot of looks, and you hear it all the time. So this looks like a great project for household tweaking. So to approach it scientifically we have our problem description:

Problem description
Smoby be fun trike has a >80 dB noise level while moving on the side-walk 

Given that all 3 tyres are made out of hardplastic and there is no suspension what so ever, these are problably the biggest noise makers. Then again there is this cool bucket at the back that can be used to lug things around. This bucket is directly connected to the rear wheel base causing it to pick up all the vibrations of the wheels and amplifying it with its big spherical surface. 
H1 - The hard plastic tyres are the main noise makers 
H2 - The bucket at the back is the second biggest noise maker 

Get the noise level down by 10 dB

Ideas anyone?

dinsdag 26 april 2011

Aero Snap

At my work i'm using a windows 7 laptop and was really enjoying the automatic resizing app. What it does? It automatically resizes windows in 3 different flavours:
If you drag it to either the left or the right your window will resize to exactly half of the screen width on either your left of right half. If you drag it to the top, it will automatically full screen your window. Cool huh?
Drag it away from the snapped position and you get your old size back, brilliant! I use it a lot since I have this big widescreen and one window will easily fit half the screen. But since I'm lazy and don't like resizing I used to just full screen everything. Now I can arrange it all neat and tidy next to each other with a simple motion, yay.

Now comes the good part, being a sort of lazy person at home to I would like to use it there as well, but I have windows vista... Thankfully there is a God and someone was inspired (this word actually means "given in by the spirit", from "in spiritus" and that sort of thing) to write a program to exactly that for windows vista and xp! double yay!
It's called Aero Snap and it works just like the win 7 snap feature. Simple, clever and powerfull as the developers put it :)
Visit the website here; http://www.aerosnap.de/index_eng.htm