Mar 192014

After being challenged to use a small motor to make something simple and interesting, first thinking was on variations of a useless machine, but seeing just how many already exist, the following simple “climber” was put together in 10 minutes.

Thread climbing motor

Thread climbing motor

Mar 192014

The initial goal was to quickly make a cheap, but usable camera copy stand. Previous post shows it took five attempts to get to a usable version!

The evolution included:- improved working space, stability of camera and work area, linear bearing mounting to reduce stress/wear and improve movement, push button height control.

Further Evolution that “might” get added:

  • add limit switches
  • add quick release clamps to further stabilise camera at chosen height.
  • Lighting needs large range position adjustment for two or more lights.
  • Easy addition of light box/filter sheets or plastic milk bottles.
Camera copy stand 5 - usable

Camera copy stand 5 – usable

Mar 192014

Photo gallery shows evolution of cheap camera copy stand creation to take overhead closeup photos of objects Each version was made mostly from items on hand, except for a few nuts and bolts and the last two versions used rods, linear bearings and stepper motor donated by the XinCheJian City project (thanks guys).

Each version “worked”, but until latest one had plenty of issues. Latest version also makes it really easy to adjust the height by pushing and up or down button connected to an Arduino Nano a XinCheJian designed H bridge motor controller and a stepper motor driving a ball screw. Plus still required a heavy counterweight, as seen in the last photo.

The biggest challenges were doing it cheap and getting rock steady mounting of the heavy camera and vibrations from nearby traffic (was highly noticeable!).

The final version is shown in the next post. Also not shown is version based on City project using belt to drive the slide – it also required counter weight. Did not refine it further as the rod mounts were too close together and not aligned accurately. Also not shown are the different attempts at lighting and rotating/tilt table to place objects.

Camera copy stand 1 - unsteady

Camera copy stand 1 – unsteady

Camera copy stand 2 - unsteady

Camera copy stand 2 – unsteady

Camera copy stand 3 - steady, but hard to adjust height

Camera copy stand 3 – steady, but hard to adjust height

Camera copy stand 4 - small work area

Camera copy stand 4 – small work area

Aug 072013

SeeedStudio Xadow unboxingFirst impression of Xadow is very good! There a lot of parts :), small – a bit smaller than end of my (man sized) thumb, but all look very well made and ideally suited for wearable items like those the Xinchejian Assistive Devices project is creating.

The SeeedStudio wiki has detailed page on each Xadow device with instructions on how to use, sample code, schematics, eagle files and if required libraries and some pages also have links to data sheet and other related software. Next step is to plug in and use, but that will have to wait until tomorrow :(

A big thanks to SeeedStudio for sponsoring the Xinchejian Assistive Devices project with the Xadow! Asked SeeedStudio last Wednesday evening to sponsor, they approved next day, Friday gave them address, shipped Monday 5:45, arrived 10am today, Wednesday.


Jul 042013

Kicked off establishment of “Helper sessions” and making assistive devices in a talk at Xinchejian.

Seems like there is a fair bit of interest – so these sessions will hopefully be be ongoing and produce some fun and “usable devices” (haha).

The trimmed presentation (cut out the waffle about me) has been published here as pdf and odp because XCJ blog and wiki have file size and type restrictions.

Started Xinchejian wiki pages for “Helper sessions” and making assistive devices.

Jan 272013

A friend in XinCheJian hackerspace Shanghai asked me today what I have been up to. I was thinking not too much, as I have watched quite a few movies (Sleep Dealer is pretty good, Avatar was way better than I expected) and re/read several books & magazines, but then I started to list some of the things I have been doing…….

  • PartTester – built 2nd board with 1% R – did not work, and now 1st one not working – same issue, eventually worked out LCD had partially died on trip home from China.
    • Looking into ways to do improved or auto-calibration
    • As part of above, part of X-bot work discovered that Gerbers used for PCB production have an electrical issue where 328 processor digital ground is not connected. This is only in the Gerbers – the schematic is correct!
    • Red circle in photo highlights difference between “good” gerber (blue) and my gerber with missing ground connection.
    Gerber issue ground not connected to Atmega328 ground!

    Gerber issue ground not connected to Atmega328 ground!

    • X-Bot – learning SMD soldering (old, unrefrigerated solder paste = :(, new = :) )
      • Made a pogo pin ISP connector to easily test if processor was working
    • Playing with el-cheapo Taobao STK500 programmer (good in HV mode, but can’t get it working in ISP mode)
    • Fighting several nasty computer issues
      • XP system freezes for 1/2 to 3-5 minutes yet CPU is at 1% and no other symptoms or errors!
      • XP ongoing anti-virus software instability issues
      • battling security update issues on XP and Lububtu
      • Lubuntu intermittent keyboard & mouse issues – only some keys/buttons work!
      • Lubuntu SMB file copy issues
      • Lubuntu “system problems”
      • Lubuntu restoring backups – path too long
      • Unsuccessfully trying to install Windows 7 to SSD and user directories to different disk
      • Unsuccessfully trying fix injet printer ($$ cartridges, cleaned, factory resets, extra cleaning…..)
      • …..
    • Replacing swimming pool pump (now pool is leaking – think it is drain system)
    • Car window electric winder replacement
    • Fixed front door lock
    • Home Theatre – fixed bad solder joint that stopped right channel working
    • Toshiba SD-K310P DVD player won’t play disks – seems like region free hack has stopped working
    • Dish washer – bottom arm won’t spin .. ongoing effort to fix
    • Backyard jungle:-
      • Getting rid of dangerous European wasp nest
      • Digging ditch for irrigation system repair
      • Hacking away at six months growth (two trailer loads so far), have not even started on the 80+ meters of hedges yet!
      • Watching Cockatoos, King Parrots and Roselas
      • Saw a falling star
      • Cleaning up flood in garage last night due to major storm – we were lucky – could hear clean up with chainsaws nearby.
      Backyard Cockatoos

      Backyard Cockatoos


      Backyard King Parrot

      Backyard King Parrot


Oct 232012

The video shows three SwarmRobots being controlled by one InfraRed signal – sorry for the poor video quality.

Looking at ways to have some sort of SwarmRobot display for MakerCarnival in Shanghai in early November, found this AtTiny 2313 code which can decode RC5 IR. It compiled, loaded and ran (verified looking at serial data output), but it did not detect IR from several different remote controls tried.

Using this Arduino code, (which uses some really nice multi-protocol IR receive and transmit libraries) it was discovered that all the remote controls used where NEC protocol, not RC5! Research indicates the NEC protocol is very common in Asia!

Rather than find NEC code for the AtTiny, or write code decode NEC, I used the above library to send RC5 and now a SwarmRobot can receive commands and as the shows, several SwarmRobots can be controlled at the same time! Kept using RC5 because it actually sends two sets of information an ID and a command, so this really fits controlling robot X to do command Y, or group z of robots to all do same command.

The code is on GitHub: SwarmRobot AtTiny2313 and the Arduino transmitter.

Oct 162012

Success:- Using one InfraRed transmitter LED and four receiver LEDs for 360 degree object avoidance. The program logic is very simple at present.

Unfortunately the setup is not yet reliable – works one day but not the next and there are still some initialisation issues.

Biggest issue seems to be that there are huge variations in the functionality of IR receiver LEDs and we have not found matching data sheets for the two types we are using!

Sep 092012

Three Xinchejian SwarmRobots

Had fun at Shanghai Barcamp Fall helping to show off Xinchejian’s SwarmRobots. It was great seeing how all the children (young and old) explored the robots ability and asked heaps of questions!

Also helped with a presentation about Xinchejian’s SwarmRobots and the AFRON $10 robot competition and I gave one presentation on one of my favourite topics “Instantly turn your project into a kit” available in Libre Office odt and as a power point. It has a LOT of pictures and includes three video picture shows, so it is around 10MB!

May 192012

Promotion of this idea has focussed so far on the creators or builders of projects creating and publishing a shopping cart from the BOM to create the easy purchase kit. This is very challenging for anyone not experienced in electronics and sourcing of parts! Here are a few snippets of people talking about this issue.

Ihsan, Littlewire project wrote:

Being a full time researcher/student and preparing an OSHW product is so exhausting …

Bunnie has several very interesting posts on part sourcing issues. Bunnie, Mitch Altman and others often travel overseas to the manufacturer and especially check on parts. Even fledgling projects like MCHCK travel overseas trip trying to get cost from $5.85 to $5 ($7 if use someone to sell/support).

Maybe once you have done it ‘many’ times and restrict yourself to a fairly standard process and parts, it gets easier, but for most of us, those first big hurdles remain. Even very experienced project designers have challenges, and as Bunnie has posted, this is an issue for commercial companies.

Ian from DangerousPrototypes has almost 24 products totalling almost 1900 items (not counting Tshirts) in stock at his MAIN supplier (retail value $US40,000) said:

… evidently Seeed was plagued with these problems in the beginning and now they swear by the broker. ….. Seeed has more experience than I will ever have sourcing parts, and this is how they do some of it, so I thought it was an interesting meeting to share. I’ll probably never buy a bulk lot of chips ever.

There other ways than doing it ALL yourself, to turn a projects BOM into a shopping cart, or even a full kit. These alternate approaches can be especially helpful to those with little experience in sourcing.

One partial step in this direction is the just announced Club Jameco. Yes this is commercial, and no, I have no affiliation of any kind. From an open source view, the design agreement (contract) and the return that starts at “5% of Net Sales” are limiting, but Jameco have allowed designer to keep intellectual rights. Jameco also reserves the rights to sell the project any way it can but that does NOT prohibit the Designer from selling his/her own designs to others. For some people, especially those just getting into design, this might be a good way to go!

But this Jameco approach once again demonstrates again the worth of the basic idea – your project can be turned into a kit that many others will buy!  The reality of hardware open or closed is that most of the parts need to come from a commercial source!

If you are not keen on going this way, then publish your own PCB designs and a good BOM, and everyone can then take their own approach to building. Publishing your project is the key first step, then easing the pain of sourcing with good BOMs is a critical next step, even if you just publish how you sourced or scavenged and then encourage others to SUBMIT how they sourced, so you can publish for them.

There are existing commercial vendors who will review and might publish and sell your project, Sparkfun is one. Some only manufacture and do not provide any sourcing assistance, for example SeeedStudios, so that approach is harder – you need the expertise to source and supply, the where the Jameco approach does most of this for you!

Another approach is via electronics magazines, either as formal circuits, or as brief, less formal circuit ideas and then hope that one of the kit supplier companies will stock and sell the kit! Disadvantage is that magazines require a very high standard of projects and also there is only a small number of magazines publishing a small number of projects, so competition would be very high if many people tried this approach.

Hackerspaces already help members develop skills to do this and some directly assist members sell projects, so you may want to check out your local space!

An approach that does not yet seem readily available to hobbyists is use of professional services to help with PCB design rules, gerbers, part selection, price management, best production/distribution/support approach, before project is sent to  manufacturing companies like Seeed, or Mitch Altmans manufacturer Etonnet. So this is a shout out to for someone to create such a business!