Spice World! » Crafty

Maker Faire UK 2010

cyberspice — Thu, 22 Apr 2010 01:14:33 +0000

So in the middle of March I was panicking about whether I would get everything ready in time for Maker Faire UK. Like last year Maker Faire UK was held at the Life Science’s Centre in Newcastle-upon-Tyne as part of the Science Week there. Unlike last year, this year I had been accepted as an exhibitor and was going to display a variety of projects, so I took the Friday as vacation for final preparation and I needed it.

The theme of my exhibit was the mix of tech and craft. Basically it was a collection of projects I had been working on and thought were good enough to display.

‘Programmable’ Earrings

Recently I started doing bead work, making necklaces and earrings and so on. One day when doing some electronics I realised that components would make awesome earrings. I then thought if you’re using components why not make them actually do something. So I prototyped up a design based around an ATTiny part that I thought would work and thought about scaling the design down to something that could actually be worn on the ears.

This turned out to be a bit of a learning curve. The only way I could do it was to resort to surface mount. Something I had never done before. Also I needed to product the PCBs professionally for the project to have any chance of working. Also something I had never done before. So this required me to learn to use a PCB CAD package. Yet more learning curve. And to add to the pressure because of the turn-round time on the PCBs I had one chance to get it right. I waited with baited breath for them to return from Olimex.

There were two issues with the board. The holes for the LED leads were too narrow. I fixed that with a pillar drill. Also the outline for the battery (which is mounted on the bottom of the board) was printed on the top of the board. That was my mistake since I created the batter holder component in the CAD package. I fixed that with judicious use of a craft knife to scrape away the print. I soldered everything up, programmed the micro-controller, and they worked.

They are light and wearable. The software carries out PWM on three RGB channels varying the colour of the LED. The colour pattern and speed of flashing changes with light level. The size is limited by the clearance of the LED and LDR leads and the battery. They were very popular and I may have to make more due to interest.

Knitted Cthulhu

This was a fun little project. I found a pattern for a knitted Cthulhu on the web. Unfortunately I’ve mislaid the link right now but I do want to acknowledge the author so when I’ve found it I will update this post. The knit was fun in itself and included knitting in the round, adding and removing stitches, and i-cord.

However because I am me I wanted to stuff electronics in to it. So rather than using beads for eyes I used LEDs. I built a small circuit on strip board based around the ATTiny part which drove the two LEDs and used a mechanical tilt switch as an input. Additional output was via a piezo-electric sounder. The tilt switch was mounted upside down so that it was normally off. However shaking the cthulhu would activate it.

A software algorithm carried out key de-bounce and counts the number of ’shakes’ within a set time and drives a state machine that flashes the eyes and makes noises dependent upon the speed of the shaking. The children loved my cthulhu.

Beebthernet

A while I go i wrote a blog post about my Beebthernet project. Well since I was getting PCBs made anyway I thought I’d use the space space available to get a PCB for the parallel port/SPI version of the Beebthernet circuit.

I was hoping to have written a twitter client in time for Makefaire but all I’d gotten was basic sockets working. However having a stand with a BBC Microcomputer connected to a flat screen monitor and a network was interesting to many people who attended the fair. In many cases parents would tell their children how the BBC micro was the computer they used at school.

Temperature Sensing Hat

This project turned out to be a work in progress so I took it anyway together with some tools in order to continue to work on the electronics. The hat itself is based upon a design in Stitch ‘N Bitch which is an excellent book. It is the sequinned hat but without sequins however unlike the hat in the book mine has a long i-cord ‘tail’ from the top of the hat than hangs down the back. The tail houses a temperature sensor in the end.

The rest of the hat is intended to be covered in small LED beads but they were not finished for Makerfaire. The beads are an idea from Leah Buechley and are constructed from a surface mount LED and two beading crimp rings solder to each terminal. I chose gold and silver rings so that I could tell the polarity. They are awfully small and fiddly to make.

My exhibits seemed to go down well with the public. I ended up being interviewed by the BBC for their Pods and Blogs show on Radio 5 Live. And then I was filmed by the reporter’s colleague for a YouTube project.

I have to admit I don’t look my best since I was stressed and this was early on the Saturday not long after the faire opened and I hod gotten up early that morning to drive up to the event and set up my things.

The faire was very enjoyable and it would be great to be back there again next year. Hopefully I would be more organised this time. There were people I knew there but many more I didn’t and I made some new friends among the exhibitors. I would like to thank Molly and Kat who were my support team and who took over talking to the public when I needed a break, food, etc. I did get a chance to look around the faire and I have to admit the stars of the show were the musical tesla coils they were both awesome and loud!

Newcastle Maker Faire 2010

cyberspice — Mon, 11 Jan 2010 17:08:44 +0000

I am delighted to announce that I have been selected to exhibit at Newcastle Maker Faire. The theme of my display will be crafty geekery.

I am intending to take along items which are a mix of traditional crafts such as knitting and jewellery making combined with tech. For example programmable earrings, a temperature sensing hat and a bag that has a proximity detector and RFID tag so it can detect its owner.

I am also going to show off a couple of my other projects like an ethernet adapter for a BBC microcomputer and a “Mood Wall” (It analyses twitter tweets for the mood of the content displaying patterns and colours which reflect the prevailing mood).

Hopefully I will see you there!

Ribbed Scarf and Beads

cyberspice — Thu, 24 Dec 2009 14:09:18 +0000

For those who want to know, this is how the ribbed scarf turned out!

I have given it to one of my my sister’s as a gift. For the other sister I made her some beaded jewelery.

iPhone cosy

cyberspice — Tue, 01 Dec 2009 15:42:43 +0000

A short while ago I went down with the ‘flu’. Usually in these cases the best thing for me to do is rest and sleep. But eventually I get bored so I have to find something to do. So this time I sat in a recliner, watching a movie, whilst teaching myself to Purl. I wanted a project I could finish in an evening to use my new found skill so I modified the “Cricket’s Cell Phone Cozy” design and learnt to do stockinette stitch and add and remove stitches in rows. Below is the result.

It has a couple of things I could improve on. I put the cutout for the headphone cable on the wrong side and you have to take it out to charge. The next one will have a button hole type slot in the bottom for the charging cable.

Knowing Purl has meant I can do ribbing so I’ve started knitting a ribbed scarf out of some great multicolour yarn.

First scarf finished!

cyberspice — Mon, 16 Nov 2009 13:11:46 +0000

I finished my first knitting project in a long long while. Its a simple knit scarf of 24 knit stitches per row in Rico Design “Roxy” yarn (73% acrylic/27% new wool – 50gm/60m – Colour violet 007). It took four balls to get a decent length using 8mm needles.

Finishing it off turned out to be problematic. I didn’t realise how much yarn I would need to bind off and ran out half way through. This meant I had to undo the bind off which wasn’t easy and I dropped at least one stitch doing it. I then had to unknit a few rows to give me the length needed and to be able to correct the dropped stitch. Whilst doing this the yarn broke. I ended up having to lay the piece flat, take it off the needle, pull off several rows and then carefully rethread the needle. I succeeded though and here it is.

Being crafty

cyberspice — Tue, 03 Nov 2009 00:37:44 +0000

Knitting was once a necessity if you were anything other than very rich. My grandmothers’ generation all could knit. My mother can knit but many of her contemporaries do not. Knitting when out of favour especially amongst feminists who saw it as “women’s work” (even though there is a rich history of male knitters) and everything they were trying to fight. But a new generation of feminists have emerged, many of them geeky women, and they are reclaiming knitting. These third wave feminist knitters think that rejecting the craft devalues the work of past women and rather than rejecting it we should reject the opinion that knitting is in any way a second class activity.

When I was very young my mother taught me to knit. I knitted a small red stuffed bear which my mother probably has stored away somewhere. I haven’t really knitted since then, until now.

A couple of months ago I decided to give it another try so I ordered both Stitch’n'Bitch and The Happy Hooker from Amazon. These books, by the same author Debbie Stoller, are partly teach-you-self books and partly pattern books for knitting and crochet respectively. The approach the crafts in a fun way working through from the basics to advanced techniques with instructions and diagrams. The second halves of the books comprise funky patterns, such as hoodies, alien scarves, fingerless gloves and so on. These patterns are devised by young knitters and crocheters, by a new generation for the new generation. They are an excellent buy and thoroughly recommended.

My current project is a beginners scarf. Knitting is like cycling you never really forget how to do it and its amazing how quickly you pick it back up again. I find knitting relaxing and carry wool and needles everywhere. I am learning slowly but it is now something I will stick with. I’ve already had a request for a scarf from my sister and with Christmas two months away there are bound to be a couple of gifts I could make for people. I haven’t really tried crocheting yet so that’s my next challenge.

Breadboard power supply

cyberspice — Mon, 14 Sep 2009 12:17:53 +0000

Last Sunday I woke early so I started on a project I’ve had in mind for a while but not gotten around to doing. I built a power supply module that plugs in to a breadboard. There are a few kits for these kind of things around from Adafruit and others but I had slightly different requirements.

My basic requirements were 5V and 3.3V supplies with the unregulated supply coming from a power adapter plug. I built the circuit on strip board as I had some available, it saved me designing a circuit board, and the holes lined up. The size of the board was set by the width of the breadboard together with how much of the breadboard I wanted to obscure. I also wanted indicators for the unregulated supply, the 5V supply and 3.3V supply so that I could spot any faults. And I wanted it to look relative tidy. This is what I came up with…

I kind of put the cart before the horse since I didn’t have a circuit when I started. It was built basically from a design I had in my head. Its a fairly text book design with a diode to protect the circuit from reverse current, smoothing capacitors in to the regulators and smoothing capacitors on the outputs. LEDs and current control resistors make up the rest of the circuit. The electrolytic capacitor values were basically based on what I had available. I suspect a 100uF on the input smoothing would be better. The schematic is below.

I like my electronics to look neat so I laid out the major components to ensure the board was symmetrical, the LEDs lined up and it plugged in to the breadboard without issue. Everything else was fitted around those components. There are no breaks in the tracks on this circuit although there are a couple of wires underneath to provide the GND ‘plane’.

Finally here’s a close up of the board. This is annotated on Flickr so you can see what does what.

All in all a nice way to spend a couple of hours on a Sunday.

Beebthernet

cyberspice — Thu, 03 Sep 2009 22:51:18 +0000

Well I have a name for my project of getting ethernet on to my BBC Microcomputer. Its now called Beebthernet. After some prototyping on copper strip-board and testing I revised the schematic for the interface.

The new schematic is below as is the almost completed interface. The LEDs and their resistors are not on the board. Clicking on an image will take you to the Flickr page where many of the images are annotated.

Unfortunately it doesn’t work. I can read data fine but I can’t write data. I looked at the bus and the data is getting to the module so I re-checked the timings. Normally peripherals are slower than the devices trying to read them so the issue is slowing the processor or bus down. However this is a modern peripheral and at least a 30 year old processor design. The timing specification for a 2MHz 6502 says that the data bus will be stable ay a minimum of 110ns after the clock E2 goes high. Since reads and writes are made when E2 is high the /RD and /WR lines, which are generated from E2 and the R/W line, will go low sooner than that. The specification for the WIZ812MJ says that the maximum time take for the data lines to stabilize is 18ns. I.e. the data bus doesn’t stabilize in time. I need to work out a way of delaying the write line signal change by 100ns.

So I then knocked up an SPI version of the interface on breadboard and connected it to the User IO port, which is connected to port B of the 6522 VIA, on the BBC Micro. I wrote a bit banging routine to read and write to the WIZ810MJ in SPI mode which, although is the slowest mode available, will work what ever the speed of the IO. It worked! I managed to set the MAC address and interface, netmask and gateway IP addresses and pinged the device from my MacBook. The breadboard set up and results of the ping test are below. Again the images are annotated on Flickr.

Fun with a BoArduino

cyberspice — Thu, 03 Sep 2009 12:20:44 +0000

In March I went to the first Makerfaire in the UK. The Newcastle-upon-Tyne Makerfaire was part of Newcastle Sciencefest. Its not that far from where I live so I drove up there for the day.

There were lots of kewl stuff as you’d expect. I particularly liked the electro-mechanical fire breathing horse robot. Amusingly I met one of the Microsoft guys who’d demonstrated the Microsoft interactive table at PHP London. He was there with his cheap, home brew, version of the table which used back projection of the image and a camera to detect the finger position. The guy with the UK101s who I’d met at Techadventure was also there.

Naturally there was an O’Reilly stand as they are publishers of both Make and Craft magazines. They had a pile of kits from Adafruit including the boArduino. This is an Arduino clone designed to plug in to a breadboard. There are two versions. One with a USB to Serial adapter on board and one which has a power supply onboard but requires TTL level serial which can be easily supplied by an FTDI lead. I bought one of the latter.

The kit languished on the shelves at my computer workstation until about a month ago when I decided to solder it together and play with it. Its a through hole double sided board which is relatively packed and so requires some experience of soldering. Apart from stupidly soldering in a LED the wrong way around and then having to desolder it and obtain a new one I had no problems. It worked first time! Limor aka Ladyada, who designed it and runs Adafruit makes good stuff.

I videoed it using my G1 phone (hence the poor quality due to low light). I have the Arduino IDE running on my MacBook. The FDTI lead is based around a common part with easily obtainable drivers for Windows, OS X and Linux.

Jewelry Tech

cyberspice — Thu, 28 May 2009 11:23:04 +0000

I’m doing crafty activities again. One of the activities I’ve started is making earrings. There is a fantastic store called Yum Yum Beads, in Leeds where I live, which I love. It is a complete cornucopia of all things dangly. One of the things I wanted to do was make a pair of earrings which reflected my inner nerd so I have made a pair of Magic: The Gathering D20 earrings.

They are made very simply by taking a pair of the giant spiral containers, which are usually intended for holding semi precious (or otherwise) stones, and a pair of earwires. I simply slipped the wires on to the spirals and closed the end off with a touch of solder.

The great thing is that the D20s are removable and so can still be used