Sunday, October 14, 2012

Simple Low-Pass Filter

After the odesk post, I did some major improvements in the firmware, and thus it wasn't as important to hire anyone anymore.

I've also looked into the Kalman filter, but for now, maybe a simple Low pass filter is enough...

Why? Well, just look at these graphs:

Raw Data

Low-Pass filter test 1

Low-Pass filter test 2

Isn't that lovely? I mean, it's pretty clear what is what. Obviously the data should be smoother, and is something I will experiment with some more. In a way though, it's good like that because if this can be handled, better data will obviously work as well! There will be a "calibration" mode where one will teach the device "walking" and "running", so what values that actually means, shouldn't matter as it will be based on the "calibration". In this test, one could say average of 500 is running, and average on 250 is walking, which is funny as 250 is half of 500... :)

So, I tweaked the low pass filter to put really low value on current raw data and I got this:

Low-Pass filter test 3 - 0.005

Low-Pass filter test 4 - 0.001

Look at that! I didn't even bother marking what is walking and running here as I suppose that is quite obvious! The main problem here though is that it will not reach 0 if you stop too soon... I guess that can be solved by just implementing some kind of "idle" timer of some sort... Again, it's only a problem when there is no data coming from the sensor, aka, no movement. So, I suppose a simple idle timer could just send 0 after a short while and that should solve that issue.

Wednesday, September 12, 2012

oDesk - Treadgaming Firmware Improvements

I thought I would give oDesk a try. And what better than to improve the firmware that is making this project stall for too long?

I'm busy with other projects as well, so I thought, why not pay someone to help me getting this project out there?

Thing is, I really want to the first impression and the quality of this product to be amazing! Which is why I haven't started selling seriously yet. I want the initial firmware to be useful, but the raw motion data I currently get just don't want to play nice with me. So, I put this up:

And hopefully, there will be someone that can help me with the things needed to get up to par with the quality I want before I sell this.

I'm also working on that "Mouse add on", which will be put up on Thingiverse as well, so people can create their own "Open Source High-end Mouse".

I just want the starting point to be an easy one. Naturally, then I'm hoping for community improvements. :)

Sunday, May 13, 2012

3D Printers Galore

It's almost getting ridiculous of all the 3D printers popping up these days.. and I'm sure more will come. Some are good progress, variety/derivatives, some just feels like greed. However, I like that the community is exploring possibilities and testing boundaries. That is a must for it to develop.

Here is a few 3D printers out there at the moment.

Currently, I'm looking forward to the high resolution projects.
We have DLP-Based Resin Printer and Lemon Curry, which I'm really looking forward too. However, the B9Creator just popped up at Kickstarter.

Sunday, April 15, 2012


Extruding chocolate isn't anything new, but it's something I've also thought of doing with my 3D printer. And lately, there have been more activity about extruding chocolate, so I thought I post about it.

First of, we have this super expensive deal:

which those that follow me and 3D printing know just feels like a rip-off. Sure, you supposedly get everything ready to print with chocolate, but £746.40 ($983) is just ridiculous. If you buy a RepRap printer you can just print a chocolate extruder part and print both plastic and chocolate with your printer. Although I'm sure you could replace the extruder here to print with plastic too.

There is even an excellent post about one here:

And on Thingiverse you can find: - Universal Paste Extruder for 3D printers - Chocolate Extruder - ultimaker syringe extruder II - Frostruder MK2

This is also an interesting read:

Tuesday, February 21, 2012

3D Printing Software is Great!

A while back I had some terrible experiences using 3D printing software. Since then though, it has improved substantially! Because of my blog post a guy named Kliment started to work on improving the software. He wrote Printrun from scratch, which is a python based package containing code to communicate with your 3D printer. It also has a nice GUI frontend called "pronterface" which will make the experience even better. Even for beginners!
  • is a library that makes writing reprap hosts easy
  • is an interactive command-line host software with tabcompletion goodness
  • is a graphical host software with the same functionality as pronsole

More info here as well.

I have been wanting to write about this for a while, but there has been so many improvements in short bursts, so as soon as I would have started, new cool things would have been added.

Just look at these screen shots:

Man that is sexy! The red lines in the middle there are also updated while printing so you can see where its at.

You are also able to click the middle area and get a new window where you can navigate through all the layers by scrolling the middle mouse wheel. You can also move around and zoom in and out in the grid with the mouse.

A long wanted feature was to show estimated time. Even when first reading the gcode, it gives you an estimate (which usually is quite correct. Just maybe a minute or so off). It will also show you the estimated time during print, and this will be updated during print, making it more accurate the longer it shows.

Before you use this program however, you need to take your 3D object and "slice" it up. For that there now exist a heavy updated and simplified program called Slic3r. Although, you can also use Slic3r through Pronterface! It's a simple program with many of the neccessary settings you want to tweak. There is also a trimmed down skeinforge program called SFACT, but personally I prefer Slic3r.

Here are two screenshots from the program:

Print Settings tab:

Printer and Filament tab

Here is a great blog about 3D printing and about Slic3r settings.

Slic3r is Nicer - Part 1 - Settings and Extruder Calibration
Slic3r is Nicer - Part 2 - filament and printing
Slic3r is Nicer - Part 3 - How low can you go?

Slic3r fill information can be found here.

After being on reliable skeinforge, I thought it was time to test Slic3r, as that is simpler and does a better job at creating great gcode. It's also faster generating that gcode data. Out of the box it was quite cool, although I had some flow issues. However, just the generation of the code went from minutes to seconds using Slic3r compared to skeinforge. The generated code was also cooler, as the movement was better. You can even specify % of slower speed for the first layers, to let it all settle and get a nice extrusion flow. After the first layer, the movement was just a joy to look at, compared to what I had in skeinforge. I will keep my skeinforge settings, and really, after coping over common values to Slic3r I ended up with a real, clean, and nice print!

I had start code which would:
1. Start heatbed (as soon as possible as this takes the longest time)
2. Home X and Y.
3. Wait for heatbed to reach temperature (say 70C), but I want to reach 80C so,
4. Heat extruder, and continue the heatbed to target.
5. When heats are reached for both, home in Z.
6. Print!

However, with a mix of Marlin firmware and Slic3r adding temperature gcode as well, there were issues with actually starting the print. It seemed to never continue even though the temperatures were reached, so I removed all that temp code added by Slic3r and went back to Sprinter firmware and it worked! I also simplified to:

1. Start heatbed (as soon as possible as this takes the longest time)
2. Home X and Y.
3. Wait for heatbed to reach temperature (80C).
4. Wait for extruder to reach temperature (225C).
5. Home in Z.
6. Print!

UPDATE: Setting temperature to 0 in Slic3r will make Slic3r not add any gcode for setting temperature, which is perfect, as I do that in my start code myself.

So, currently, I'm using Sprinter as firmware, Slic3r so slice up the 3D object(s), and pronterface to print and work with the 3D printer. Works great!

Monday, February 20, 2012

My Image Used In a TimeLapse Video

Well, seems my image with the parts taken on the table was used in the video here (it should even be the still image shown before playing the video):

RepRap MakerGear's 'Prusa Mendel' [Full Assembly TimeLapse] from Haas van Spaandonck on Vimeo.

I don't mind this though. Would have been nice with a heads up though... oh well...

Friday, January 20, 2012

Sunday, January 15, 2012

Start of Mouse Add-On

I wanted to play around with the Kinect scaning something, and I also wanted to start with what will end up being a plastic add-on to the device so it can be used as a Open Source High End mouse!

My device is already ready to be a mouse. What is missing is the enclosure and some extra hardware for buttons and such.

So, I scanned my hand, ran it through MeshLab to clean it up/add more vertices to make it smoother. After some smoothing of the mesh in Blender, it ended up like this:

Note though that this is far from done. It would be nice to keep the mesh form as much as possible because it would be a perfect fit for my own hand. However, I guess I will smoothen it out more so it will fit others. The whole thing will be available for everybody later either way, if anyone wants to tweak it. Also, I need to modify it so it can be printable and make room for buttons. Still, it's quite cool to have this scanned object of my own hand! Saved me a lot of time as I don't have to create this from scratch. It is also more ergonomic! Furthermore, it is easy to mirror, so I end up having a left hand as well (for lefties).

Monday, January 9, 2012

TOOB Immersive Dome Display

I was talking about jDome earlier, which is nice, but in my opinion waay too expensive. So, I just now came across this:

which I really found through Kickstarter here:

Now, not only does it look better, it's price is better too. $800 vs $2293. At least now as it is on Kickstarter. Will probably be more later. This is really interesting though, and I'm tempted to be a backer on it actually... What is good as well is that they seem to have a factory both in USA and UK, so that will keep shipping costs lower...

One thing I've noticed though, is that with the jDome you seem to be more inside the dome, compared to the TOOB one... That would mean better immersive experience...

Thursday, January 5, 2012

"Personal Trainer"

I came over this Dragons Den (UK) episode where a guy talks about his "Personal Trainer" package that is related to what I'm doing. Season 2, Episode 6 aired 20 December 2005. What is interesting there is trying to figure out what Duncan Bannatyne is really saying.

"... none of it worked. The only thing, that could any chance that keep somebody who's bored on a machine, is a television screen. It's the only thing that works. I know from experience. Nothing else works."

Then he says:

"I've had this screens on my cycle classes. I've thrown them away. .. because they don't work."

He got a point that seeing the same thing, over and over again will probably get you bored though.

I would say that the execution here is the main bad thing. Presentation isn't good either. They have sold 130, which is quite cool. Also, the main complaint is about the distance from device to PC. Too bad he didn't explain how he connects to a PC, because using a cable isn't all that hard.. On that note, I've been thinking using WiFi, or Bluetooth, but that makes it more expensive... and more complications regarding regulations using the air for communication.. particularly on a global scale... Could be possible for a version 2 though...

Tuesday, January 3, 2012

Filabot: Plastic Filament Maker

In case you missed this, there is an interesting project on Kickstarter which is about taking your current plastic objects, grind them down, and recreate filament to be able to use with your 3D printer and reprint something with it!

I'm not sure how well the product they are working on will end up, as it's hard to read their cridentials. Plastic is complex chemicals... However, I'm sure this kind of product will come sooner or later...