Sunday, March 19, 2017

Raspberry Pi Hints and Tips

A collection of links to useful places for RaspberryPi enthusiasts:

Wednesday, September 7, 2016

It has been a few months since my last posting. I have lots of projects of interest and organising time to do them should be aided by tech, but just isn't. ToDo, task lists, calendars, etc. should be so much better than they are.

GMail recent added the auto post link to GCal which is okay, but still limited.

Still looking for a better way.

Monday, May 11, 2015

To sit or not to?

With the launch of the ConnectTVT Open Devices Lab there's a new opportunity and new facility within GROW. During launch week several people have commented upon the height of the display stand's, and this got me thinking about a discussion that has been a work meme in recent years - standing desks.


What are the pros and cons now that people have had some experience of using them?


I found a number of interesting articles on the Web discussing blogger’s experiences of using both standing and standing/sitting desks.


If you want to build one for yourself, then just ask at your local MakerSpace (e.g. rlab.org.uk), they will have the facilities to help you build one from existing materials such as those found at IKEA as shown in this guide (http://iamnotaprogrammer.com/Ikea-Standing-desk-for-22-dollars.html)


But, what type of desk to build?


Constant standing seems to be as bigger a problem as constant sitting.


In his article (http://blog.pickcrew.com/why-i-killed-my-standing-desk/) Mikael Cho decides not to continue with his desk, but introduces new ideas about exercises that will tackle such things as “tight hip” which is often the underlying culprit leading to lower back problems, and then raises the issue of our mobility as we get older and what exercises can be useful to develop muscles in the body.Studies by Kelly Starrettt found a lot of people are uncomfortable with exercises such as squatting in a keep-fit gym. As linked in the article Kelly recommends three stretches to help.


Part of a series on Networked Fitness and the Quantified Self, The ReadWrite Web  post (http://readwrite.com/2013/09/26/standing-desks-productivity) by Julia Gifford starts off saying there's lot’s of companies supporting Standing Desks, Google, FaceBook and others. She looks at the history with Thomas Jefferson and Winston Churchill noted users.


She notes positive and negative aspects that vary depending on the type of activity, standing added urgency that can destroy creativity, but it can help “get things done”, give relief from headaches and help quit smoking.


On Quartz (http://qz.com/272350/theres-a-huge-hidden-downside-to-standing-desks-that-no-one-told-me-about-2/) Gywnn Guilford discovered a huge hidden downside to a standing desk but concludes that even when the crankles made it hard to put shoes on, she never considered going back. She lists 5 points that she learned from working with a standing desk.


  • Switching is more complicated that just standing
  • Choosing a standing or a more complicated stand/sit version
  • Differences for men and women
  • Understanding the research results
  • To sit or stand, changing your work protocol


So I am wondering about others experience and views on Standing vs Sit. Should the Lab offer a choice? And if so what tasks to be facilitated on which style?

Monday, June 9, 2014

Planning a new blog for my use of the OpenTRV

I went to meetup with the OpenTRV team on Saturday. We had a great discussion about the current place and future plans for the project. Although I have been following the project and I have printed some of the first cases as part of TVRRUG and I received my tinkering kit board a while back, I was unclear what I could do with it.

I now have a Conrad FTS TRV that is the same model as the Rev2 boards have been designed to work with. Mine is a German version, but I believe it is the same as the UK FS20 as mentioned in this thread from the opentrv archives.

So I am going to create a new blog to follow the work I do on this project.

Friday, January 24, 2014

Processing and FreeNect on Ubuntu 12 64bit

I recently acquired a Kinect sensor with the intention of using it for 3D scanning of things for printing on our TVRR printer. But it seems there is a lot more I can use it for. Robots, midi and more are now on my project list.

I've got it working on various OS's  including Win7 and Xbuntu 32bit and Lubuntu 64bit. There seems to be lots of choices of software, but much stems from around 2010 and has ownership and development seems to to have alot since then.

I am obviously rather late to the Kinect game and this means I have to pick the right bones out of a pile of skelebones,

I plan to records notes here to help others that may come across the same problems.


Today I got Processing working on my Lubuntu 64bit system and able to run the Freenect examples. An option is to use OpenNI instead of Freenect, but I had Freenect installed and working already and I understand they are not compatible with each other.

I found instructions at http://www.local-guru.net/blog/2010/12/28/how-to-use-the-libfreenect-processing-wrapper-on-ubuntu the differences being my 64bit OS and my use of OpenJDK 7 (needed for PraxisLive - but that is another story) So my Paths were different and I did not remove the -m64 directive.

It compiled okay but I got an error:
java: symbol lookup error: /home/../sketchbook/libraries/openkinect/library/libOpenKinect.so: undefined symbol: libusb_init

There are several forum posts reporting this error, but no good answers. I initially thought it may be a PATH error so I double checked the paths in build.sh, I added a symbolic link in the /usr/lib/jvm/ directory for JDK 7 to mirror the one for JDK 6, but this did not help.

I found this post: http://fightpc.blogspot.co.uk/2011/05/use-processing-and-kinect-in-ubuntu.htm and in the comments found this http://fightpc.blogspot.co.uk/2011/05/use-processing-and-kinect-in-ubuntu.html#c3034086444552109525
reporting the same problem. As the main post + mentions an update advising he has 64bit Ubuntu running okay, I am encouraged to pursue a solution. The post is from May 2011 though.

and I see this reply that matched my googling:
http://fightpc.blogspot.co.uk/2011/05/use-processing-and-kinect-in-ubuntu.html#c2174108083274595404
saying: I'm assuming you have libusb-1.0 already installed in your system. The complaint is about not being able to find libusb init code. 


So I'm still not working. The reference to having libusb-1.0 installed (which I have) got my googling libusb and without reference to kinect or freenect.

This pulled up the post: http://libusb.6.n5.nabble.com/Compile-in-GCC-td7048.html from 2009 which holds a query about a problem 'Roman' was having with gcc and libusb and getting the same error.

Tim Roberts reply was:
You told it where to find the include files, but not the name of the 
library.  If the library is in your /usr/local/lib directory, try adding 
-lusb-1.0 to your command line. 

I tried this and Viola! my example loading in Processing and reported it couldn't find the Sensor. I plugged the Kinect in and a window popped up, but no images.

I ran 'freenect-glview' to check this was still working, which it was, and reran the Processing sketch, and double viola! the images came up.

A simple solution but a pig to find even with all the help of google.







Monday, November 4, 2013

TVRR 3D Printing at ECOS

On Saturday the 2nd November I had the pleasure of attending the Electronic Organ Constructors Society ( ECOS.org.uk ) meet up close to Euston station in central London.
My visit had been inspired some weeks earlier by an event at the Bracknell Gadget Fair where I was displaying the Thames Valley RepRap Users Group (TVRRUG.org,uk) demonstration of 3D printing machines
Alan Douglas was visiting the fair and had been coincidentally requested to do a talk on 3D printing at their meetup. Seeing the 3d printer so he took great interest and we discussed some advantages and opportunities that the TVRRUG approach offers
I arrived early in London and found a parking space close to the church hall where the event was taking place.
At 10 o'clock I took my TVRR RepRap around to the hall and found inside a welcoming cup of coffee, some biscuits, and a group of people of varying ages, and unsurprisingly, all male. In the church next door the sound of an organ playing and many men and women dressed smartly for a service.
To prepare for the event Alan had sent me a drawing of, what is known as a “stop”, a piece of an electronic organ which is often used in construction projects. One of the members has been casting them in plastic and it seemed a good example of something that could be 3d printed
I worked on creating a design using the OpensCAD software and printed out a sample which I took a long to be event.
A feature I had not been able to reproduce, using the OpensCAD software, was a radius on the top of the stop, this is the main difference between my reproduction and the original drawing, it is something that is possible to do, but would have taken me more time than I had available.
Alan presented his talk to the animated audience and it covered a lot of areas of general 3D printing, the opportunities and limitations. Afterwards he handed over to myself and I talked through the specific areas around the Thames Valley RepRap design,  in particular a involvement and cooperation with the Reading Hackspace (rlab.org.uk), and other hackspaces in general.
There were lots of questions and discussions about 3D printing and its role in electronic organ construction. I thank everyone I met for a warm welcome and wish you well with all your projects.
In this document I want to add some links to the sources of information and resources that I referred to in my discussion.
Thames Valley reprap user group - http://tvrrug.org.uk
Reading hackspace - http://rlab.org.uk
Manchester fablab
Faberdashery filament supplier
Meshlab
Blender
Sketchup
EagleCAD
Open Source Hardware User Group http://oshug.org


Friday, October 4, 2013

No comms in the age of comms!


The downside of number porting.

Yesterday I was woken by an unsolicited text from an online bingo provider, not for the first time. Getting fed up with them I searched and found a number that I could forward them to that deals with spam.
I duly forwarded the msg, and received a reply asking for the originator callerID. I had to tell them that it was sent from 000000, and expected to hear no more.

I have a new phone in addition and wanted to update the contacts so I know own number. I called my old phone number and found it was reported as "Temporarily Unavailable". I found I could send texts and make calls but not receive them.

Thinking the phone was faulty I swapped the SIM to another phone and now there was no signal at all. Back to the other phone and now no signal there either.

I checked the O2 status page, and it said all the network was fine.

I had a spare PAYG SIM on the same network, so I tried that and it worked fine. So I thought that it was the SIM with my main number that was faulty. I contacted my MobileSP to ask for my credit to be moved to the working SIM.

Then at 2am today I get a series of txt msgs on the 'dead' phone over a 30 min period. These turned out to be messages from yesterday, including test ones I had sent to myself.

So what did I learn. My current analysis is that the problem was caused by using a 'Ported Number' on the SIM

The working SIM is on the same network, but with a 'native' number. OFCOM documents indicate that there may be routing changes underway at the moment. 

If this is the cause then maybe porting your number is not a good move, not only does any spam follow you, but it adds another layer of 'service' to fail.