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After many (many!) attempts and learning’s.

Everything from PCB design via software, PCB manufacture via toner transfer and ensuring your board is soldered correctly has had to be designed, re-engineered and put into practice on almost a production line state of mind.

Finally the initial board is ready to rock!

Completed BeeSafe Board, Version 1

Completed BeeSafe Board, Version 1

This board features, 5 LED’s; 4 of which are configurable. 3 Temperature Sensors, input for a switch and an I2C based accelerometer. *NB* The board above only has 1 of the three temperature sensors attached as at time of writing the other two sensors were in the post.

This board connects into a Raspberry Pi via the large 26 Pin header in the top left. Connected to the Pi is a USB GPS and USB 3G Data stick. *NB* the Pi’s on board USB ports aren’t able to provide enough power to support the 3G Data stick so an additional hub or secondary PCB will have to be provided should 3G be needed (Which I suspect it will!).

In total the BeeSafe project has the following sensors and communication gateways:

Circuit Temperature BeeSafe Board
Brood Temperature BeeSafe Board
External Environmental Temperature BeeSafe Board
XYZ Accelerometer BeeSafe Board
5 x Status LED’s BeeSafe Board
Switch Sensor BeeSafe Board
GPS Raspberry Pi
3G Data Modem Raspberry Pi
Ethernet Connection Raspberry Pi

With the hardware now complete (for the moment!); my attention has turned to the software to power BeeSafe. This is comprised of two parts: Software localised on the device and software hosted in the cloud to collect, store and interpret all the data.

A lot of people have asked why I chose to use the Raspberry Pi to power this device, a micro-controller such as Arduino would have been more than capable of reading temperature sensors, XYZ data, parsing GPS data and submitting it all via a comm’s device to the cloud. But the Pi stands out as a standalone computer. It’s capable of hosting its on database, serve pages and data to other computers and networks. An Arduino works in a single hive, but a Pi could work with many.

An Example; quite often bee hives are clustered together and are known as apiaries. If each beehive had a 1-2-1 connection to the internet that would mean each hive would require a 3G stick, its own sim card and data plan. Quickly the costs of keeping an apiary online would rack up.

Using a Raspberry Pi you could create a star network, one device could become a host. Using a USB WiFi stick to create a local WiFi access point (like your WiFi at home, one hub serves many users with an internet connection). This could keep costs and maintenance down as each apiary would only need one connection to the internet.

Additionally, if there is no cell signal, a Raspberry Pi could be used as a localised storage option for all the data collected. While this means you would loose some of the advantages of monitoring your Bee Hive remotely, the data is still invaluable and could be downloaded at a later point.

The next steps for BeeSafe include a start up program that will scan the hardware and configure everything into appropriate sections. For the moment I am doing this manually using a mix of python scrips to test the internet connection, GPS data, LED’s, temperature and XYZ position.

My ultimate goal is to produce a initial start up script that will on boot, self-test the LED’s, check for internet connection, scan for temperature sensors, check for the presence of an Accelerometer and then store all this data within an XML file to be used by the default BeeSafe program.

An example of the XML configuration file is below:

<?xml version=”1.0″?>
<BeeSafe>
<BeeSafeDeviceID></BeeSafeDeviceID> #Unique Serial Number used to identify the BeeSafe
<RedLED><RedLED> #GPIO Pin number for Red LED
<AmberLED></AmberLED> #GPIO Pin number for AmberLED
<GreenLED0></GreenLED0> #GPIO Pin number for First Green LED
<GreenLED1></GreenLED1> #GPIO Pin number for Second GreenLED
<BoardTemp></BoardTemp> #Identifier for Board Temp Sensor
<BroodTemp></BroodTemp> #Identifier for BroodTemp Sensor
<EnvironmentTemp></EnvironmentTemp> #Identifier for External Temp Sensor
<MagSwitch></MagSwitch> #GPIO Pin number for Magnetic Switch
<XYZ></XYZ> #Identifier for I2C Accelerometer
</BeeSafe>


The BeeSafe Device ID is used to track and log the data submitted by a BeeSafe device, my initial thoughts were that I could use the serial number from the Raspberry Pi attached, but this quickly led to issues as should a user wish to swap out the Pi for another one, the serial number would change and the data would be lost. Additionally I did not want to tie a BeeSafe device to a specific email address as should an individual user have more than one BeeSafe active, managing each device this way could prove to be problematic.

So whats the solution?
A BeeSafe’s Device ID will be generated on demand from the cloud, as a new device comes online and communicates with the cloud for the first time, it will be assigned a device ID which will be saved to the XML config file. While this ID will not be dependent on the PI it is connected to, the Pi’s serial number will be submitted so that should the worst occur and the SD card with the config file be lost, if the same Pi attempts to reconnect to the cloud, as a new user, it will be assigned the same device ID.

From a human perspective; one user can be in control of many BeeSafe devices.
Should the worst occur and the user need to be contacted, if more than one device has an alert status (such as a whole apiary) the user would be alerted once rather than receiving multiple alerts for a cluster of hives suffering the same issue. For example, if a cluster of BeeHives have collapsed, a single alert would be sent out stating that X number of hives currently need attention, rather than bombarding the user with an alert for each individual hive.

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Manufacturing PCB’s in a small scale is often expensive, time consuming and inconvenient for the hobby engineer. Setting time aside to design a PCB, sending the design off to be manufactured and the getting it back to realise its the wrong size or worse that a pin is in the wrong place is often a costly process.

I have for a number of years been building PCB’s at home using various bits of software and manufacturing techniques. These boards were very simple and usually designed to convert DC to DC power from batteries or other sources into another voltage – usually to power a 3rd party circuit or in a pinch my iPhone.

My tried and traditional method of PCB manufacture has been to design the part using Adobe Illustrator, flip the board and print it onto ‘PCB’ toner transfer paper, iron the transfer onto a copper clad board and then etch the board using PCB etchant.

While this has worked great, it has a number of limitations; the level of detail I can work with on illustrator isn’t quite setup for PCB designing, everything is a manual process, the iron on transfer often didn’t work (well) completely and so I had to use a pen to fill in the gaps – making for a messy PCB.

Attending a MakerFair in Brighton (South Coast of England) in the summer, I got chatting to a number of people who represented ‘Build Brighton’ – http://www.buildbrighton.com

Seeing the quality of the PCB’s they had designed and made using gloss paper and a laminator inspired my to change my process.

Deciding to start from the beginning I have throw away all the old processes that didn’t work and refreshed them with new.

PCB Design software:

I evaluated a number of bits of PCB software, the list including:

  • EaglePCB
  • FreePCB
  • ExpressPCB
  • OsmondPCB (Mac only)

I finally settled on FreePCB, I was looking for something that would allow me to build without needing a schematic first. With the software it was very easy to define a PCB board size / shape and then add parts from a pre-defined library. If the part you needed didnt exist, it was very easy to add the part to your own custom library and then import it to your design.

Its worth noting that FreePCB allows the use of multiple layers per board – this is something new to me and I am keen to find a project that will allow me to build a circuit board with both top and bottom tracks & components.

Once I had a basic grasp of FreePCB, I began the redesign of my latest project dubbed ‘BeeSafe’; you can read more on that here http://www.mathewjenkinson.co.uk/beesafe-pcb-initial-thoughts-and-feedback/

Using predefined parts, I was able to define the board size (adjusted to the same size as the Raspberry Pi) move the GPIO cable to a more suitable location, place LED’s and switches and locate the 3xAxis accelerometer. The process itself was straight forward and easy to follow, I was able to adjust the track sizes and route all the connections with ease.

As the board itself was now positioned the right way around, I did not have to flip the image. Exporting to a super high resolution tiff file means that the image coming out from the printer was super crisp. The paper used in the printer is super high quality gloss paper, it has a plastic feel to the coated sheet and the toner doesn’t bleed or blur.

PCB Image printed on to Gloss paper.

To transfer the image to the PCB board is a two step process. One part cleaning and one part heat. Its important to ensure that the copper clad board is 100% clean and free from oils and finger prints as this will reduce the contact the toner has with the board and ultimately effect the end result.

To clean the board, I start with dish soap and a coarse sponge. Scrubbing the board to remove grime, oils and finger prints gets the top layer off and a final buff is done using steel wool, which brings the board up in a nice shine – removing the copper oxide layer.

From here I need to apply heat. Using a laminator and a laminator pouch I run the board through the laminator flipping and turning the board to ensure constant heat distribution along the surfaces. The end goal being that the toner melts off the gloss paper and adheres to the surface of the (now clean) PCB. I have found that that using a laminator pouch acts to prevent the paper + PCB from slipping and keeps the overall temperature stable for longer.

*NB* After a weekend of making PCB’s I can confirm there is a SIGNIFICANT difference between toner transfer with and without a lamination pouch. With the pouch returns a near 100% transfer of toner and pattern while without  can be incredibly hit and miss.

Track transfer via laminator

Track transfer via laminator

Once the board has cooled and can be handled, I cut it from the plastic surround and then submerge it in water to help dissolve the paper. This doesn’t usually take long as the paper is thin and soon falls off the board.

The next step is etching. This is a chemical milling process where the board is submersed in a liquid solution that will dissolve away the copper, any part covered by the toner will be protected and after 20 mins or so (depending on the strength of solution, temp etc) the board will be finished and can be removed from the solution. NB – do not tip the waste down the sink / toilet as it is still quite toxic and may corrode your pipes!

PCB after etching - before drilling

PCB after etching – before drilling

While the toner is still attached to the board, I drill the holes. I have found that the drill travels less and tends to protect the track below.

Finally you need to remove the toner from the board, this can be done in a number of ways. Nail polish works well, as does a quick scrub under a hot tap with a brillo pad.

PCB Being soldered

PCB Being soldered

The final step is to solder your components and test your board!

Happy Making!

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As part of my project; a small monitoring tool to monitor beehives dubbed ‘BeeSafe’ I have been designing and assembling a small printed circuit board – PCB, to collect all the sensors together.

Previous parts of this build can be found at:

http://www.mathewjenkinson.co.uk/beesafe-concept-development/

With the board printed and etched it was now time to solder on all the components and begin testing.

As you can see from the picture below; soldering is a skill I’m still to master!

Version 1 of BeeSafe PCB

Version 1 of BeeSafe PCB

Following what I thought to be a simple design I quickly found out that I had errors both in the pin layout and the physical spacing of the components used on the board.

The placement of the GPIO connector (13 x 2 lines of pins) meant that the board was in an awkward position and the cable pushed up against the accelerator / motion detector.

Physical component wise, the LED’s were situated too close to each other, meaning that when it came to solder them, they were all on-top of one another.

Its important to stress that while this PCB hasn’t been a success, it hasn’t been a failure either. This PCB came from a new manufacturing process where I used a laminator and gloss paper as the toner transfer method. As you can see from the image above the process itself was a success!

From here, the PCB design will go back to square one. I want to switch from using Adobe Illustrator to a proper PCB design software such as Eagle PCB which will allow me to design better more complex boards that can include things like silk screen’s and will be easier to scale up production should this be required.

 

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For a number of years I have been manufacturing PCB’s at home.

Nothing complex, small voltage converters  or easy to solder projects to either teach myself how to use LED’s or sensors on technology such as Arduino.

 

Homemade Power Converter PCB

Homemade Power Converter PCB

In the past I have always started my design on graph paper, marking out where the physical components need to go and then fitting tracks to them. Which at a basic level works, and works well. You know if you have enough space, where the tracks will go and what overlaps / jumps you need where.

From graphing paper the design is transferred to a digital form and is mapped out using a graphical editor – I use Adobe Illustrator. I know its not designed for PCB layout’s but when you need something simple and quick its fits the bill perfectly!

A single sided board awaiting PCB transfer. The blue sheet is the design on 'Press n Peel' transfer sheet.

A single sided board awaiting PCB transfer. The blue sheet is the design on ‘Press n Peel’ transfer sheet.

Once I have a digital copy of the layout, I invert the image and print onto ‘Press n Peel’ toner transfer paper. Traditionally from here I have used an iron (no steam setting) to melt the toner onto the copper-board, however after speaking with plenty of people at a recent MakerFair, I purchased a laminator and haven’t looked back!

Track transfer via laminator

Track transfer via laminator

Embedding the board and template in a laminator sheet seemed to work very well to retain the heat and ensured even temperature distribution across the panel.

Single PCB and a whole sheet ready to be etched.

Single PCB and a whole sheet ready to be etched.

As you can see from above the process works exceptionally well when you need to scale up from one (single) board to a multiple set.

PCB board ready for drilling

PCB board ready for drilling

Things to note.. PCB Etchant is dangerous stuff!! Its sole purpose is to dissolve metal! There fore when your done do not tip the waste down the sink..

I’ve found that being able to produce a quick and simple circuit for a project / fix it around the house has been a great help. Granted, I’ve prob not saved money over all (after chemicals, board, laminator etc) but its great to know the things I have built are being used every day in my household.

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Continuing again with my Raspberry Pi adventures and further developing my ‘BeeSafe’ project. One of the components I need to integrate is GPS module that would allow me to track the BeeHive / box should someone decide to move it.. To this end I purchased a few GPS units from ebay. This guide should get you up to speed on how to access GPS data via your Raspberry Pi / linux setup.

USB GPS with magnetic base

USB GPS with magnetic base

Plug the USB GPS into the pi, you should be able to see it detected in

sudo lsusb

Mine came up as: Bus 001 Device 004: ID 1546:01a6 U-Blox AG

Using:

dmesg | grep -i usb

I worked out that my USB GPS was paired to ttyACM0

At this point you can test your GPS device is functional and sending data by:

sudo cat /dev/ttyACM0

The next thing we need to do is pipe the GPS feed into GPSD (the gps demon) for it to interpret the data and hopefully give us something useful to use later.

sudo gpsd /dev/ttyACM0 -n -F /var/run/gpsd.sock

this command connects the output of ttyACM0 to the gpsd socket

NB: I had to ensure that the -n flag was present in this command, as trying without the flag resulted in a time out.

You should now be able to test the GPS using

cgps -s

Which will bring up a small window showing the GPS data.

Things to note; If you have any problems and cgps always displays ‘NO FIX’ under status and then aborts after a few seconds, you may need to restart the gpsd service you may have to kill and reboot the gps demon by typing

sudo killall gpsd

and then

sudo gpsd /dev/ttyACM0 -n -F /var/run/gpsd.sock

 

which will restart the gpsd service and pick up the new settings.

Now you should be able to use the GPS data for whatever your project needs; in my case I want to build a GPS fence so that if my beehive is detected leaving a known area (such as a field) then it will alert me and provide me with a GPS co-ordinate feed.

I used the Lady Ada guide on how to setup GPS devices to help me; the link is:

http://learn.adafruit.com/adafruit-ultimate-gps-on-the-raspberry-pi/setting-everything-up

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Following on my project to develop a Bee monitoring tool dubbed ‘Bee Safe’.

The next part of my project is to provide the remote raspberry pi with access to the internet via a USB 3G dongle.

Fortunately in the world we live in now; finding old / used 3G dongles is very easy to do. The one I’m using was purchased from Cex for the pricey sum of £6.

£6 3G Dongle

Newly purchased 3G Dongle

While cellular data speeds and modems have vastly improved over the recent years this project only requires sending small snippets of text with the occasional photo so high speed isn’t a priority on this project.

To pair a USB dongle with a Raspberry Pi (the computer used to power Bee Safe) you need to download and install some packages; PPPD & sakis3g

To start with download PPPD via APT-GET:

sudo apt-get install ppp

Then download sakis3g:

wget "http://www.sakis3g.org/versions/latest/armv4t/sakis3g.gz"

Unpack and make the file executable:

gunzip sakis3g.gz
chmod +x sakis3g

Then execute the script which will run with a basic GUI within terminal:

sudo ./sakis3g --interactive

Sakis has a fairly comprehensive list of connections available.

Once you have been through the setup guide the modem *fingers crossed* should be online and operational. You can now exit sakis. You will stay connected.

You can check your connection and details with this command:

sudo ./sakis3g connect info

This post was pulled together from various sources, the main two being:

http://shkspr.mobi/blog/2012/07/3g-internet-on-raspberry-pi-success/

and

http://raspberry-at-home.com/installing-3g-modem/

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Following on from my previous posts about a tool or piece of technology that can be used to monitor bee hives and the status of bee’s; I’m pleased to announce the next step of my development of this project.

Originally code named ‘BeePi’ because I was building on the Raspberry Pi computer system, I have developed it further and it has evolved into ‘BeeSafe’ – a micro monitoring tool used to monitor the status of a bee hive.

BeeSafe Features:

Accelerometer External Environment Sensor
Abient Temperature Sensor Magnetic Switch Alarm
Brood Temperature Sensor LED Status Lights

Which will allow me to work out:

Current temperature of Bee cluster in the Hive – Are the Bees still alive
Current temperature of the environment around the hive – Are the bee’s likely to be active
If the Hive is open – Is someone doing something to the Hive
If the hive has fallen over – Has an animal or something caused the hive to fall over exposing the inside of the hive
If the hive is being moved – Useful if you think your Hive is being stolen
Quick Traffic light: Red, Amber or Green Status of the Hive

This is the first picture of the base PCB that will operate BeeSafe:

Bee Safe Base PCB

Bee Safe Base PCB

As you can see, it still requires a lot of work including soldering all the components to the board and then programming the system to detect and report from the various sensors.

From a software perspective at the Hive level, I need to start writing how and what the software will do, how often it will record measurements, what the traffic light system will show to the users, what data will be submitted to the cloud for capture and in what frequency.

Next stop is the cloud.. While I have ideas on what data I want to capture. I need to nail down specifications on what I want the cloud to do and how I want the cloud to be engaged by users.

Web, Email, Text and API are all things I want included in the project but the balance is finding out the best way to include them. If your Hive was broken into – would you want a text message saying that? What about on-demand reporting about how your hives are doing? What about logging in to your hive in the middle of winter to confirm that the bee cluster is overwintering well and that the temperature internally isn’t dropping too low (a sign the bees are starving and dying off).

I hope to manufacture these boards in greater numbers once I have developed this initial PCB, confirming that all the components work in the way they should and that I have suitable demand for the BeeSafe Project.

 

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In a previous post (http://l-k.me/J) I described an idea I had to make use of a Raspberry Pi as a local sensor tool on a bee hive, a project I’ve dubbed ‘BeePi’.

Below is a small requirement chart for the projects needs and potential:

Requirement Must Have Would Like To Have Nice To Have
Internal Hive Temp Sensor Yes
External Hive Temp Sensor Yes
XYZ Accelerometer Yes
High Capacity Battery Yes
Solar Charging Battery Charger Yes
WiFi Transmitter Yes
WiFi Hub Yes
3G Connectivity Yes
Hive Disassembly Sensor Yes
RFID Antenna Yes
Weather Station Yes

While all of these could be rolled into a singular project, but it makes sense to break up development into phases based on real world requirements and (of course) money.

A lot of what is required for this project exists in singular projects already published by the Raspberry Pi community, a large following of users are making use of the Maplin USB Weather Station (http://l-k.me/I), GPIO Temperature Sensor(s) (http://l-k.me/K) and RFiD Reader (http://l-k.me/L). The use of a 3G and / or WiFi dongle makes sending data exceptionally easy as the OS will handle any of the connecting to the internet / network leaving any software to make / receive API calls and store the data where appropriate.

The use of the BeePi as a WiFi Hub is also worth considering if you have more than one hive in a location it makes sense to have a singular hub / data collecting server that all of the other BeePi’s connect to. There are many tutorials on the internet that show you how to turn your Raspberry Pi into a WiFi hub and make use of a singular 3G dongle to connect them all to the internet (Or even host the database locally).

After a bit of juggling and budgeting my Phase One build will look like this:

Internal Hive Temp Sensor
External Hive Temp Sensor
XYZ Accelerometer
High Capacity Battery
Solar Charging Battery Charger
USB WiFi Transmitter

I don’t want to host the data from the hive locally (on the BeePi), so I will write a program to gather up the sensor data periodically and then send the data to a database hosted somewhere (more to come on that as it is developed).

I want to capture the internal brood temperature, external atmospheric temperature, XYZ geometry of the hive. The BeePi will be powered by a chunky long life battery which will be maintained by a solar panel. The hive will be connected to my WiFi network via USB WiFi stick.

To aide development and keep phases in line with each other I will design any PCB’s to include the optional bits; RFiD reader, Hive Disassembly Sensor, 3G data stick. So that should I need to add these to my project or as requirements change I don’t have to go back to square one and make a new base-board.

For the sensors I am going to be using; I’ve chosen to keep things simple:

Internal and External Temperature Sensor: DS18B20 3 Pin 1 wire temperature, these are particularly handy and cool as you can connect several to the same GPIO pin but capture data from them all separately via serial interface. The tutorial guide I am using is: (http://l-k.me/K).

XYZ Accelerometer: ADXL345 a simple I2C accelerometer which you connect  via the BeePi’s GPIO Pins (http://l-k.me/M).

Power and Solar: Power will come from a 12V 7AmpHour battery which will be charged via solar panel regulated with a solar charge controller. The board I will design will take 12V and step down to 5V which will be used to power the Raspberry Pi, WiFi and connected devices. The hope is that the battery and sun will maintain the project indefinitely however as this is all theoretical (at time of writing!) I may need A) a bigger battery B) a bigger solar panel C) BOTH.

While you can source all of these components from UK distributors, I HIGHLY recommend looking at eBay and sellers who are based on HK or china as I have found the price difference to be considerable between UK and Asian sellers.

More to come as the project develops!

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*FYI this idea is still a concept and needs to be ironed out!*

It’s worth mentioning one of the great technology releases of 2011 / 2012 was the Raspberry PI (www.raspberrypi.org), a credit card sized computer powered by an ARM processor which can run a select few flavours of Linux.

One of the great selling points of the Pi, are it’s GPIO Pins (General Input Output Pins) which allows you to connect up a vast multitude of sensors, lights, relays directly to the Pi and engage with it via the command line or computer program.

As an avid bee keeper I have spent my last few summers tending to a few bee hives, growing up two colonies to hopefully gather up lots of honey for me! (a treat I love!).

At a recent bee keeping event I ran into a man who had developed a bee hive sensor that is able to be placed inside the bee hive to capture a number of different aspects of a bee hive, such as; temperature, hive geometry to name a few. It was a great product but A) well out of my price range and B) not flexible enough to further development.

So I thought to myself, could I make something similar and what would it look like. Well the short answer is yes, and below are the (incomplete) specifications for what I would want my ‘BeePi” to look like and operate.

Project BeePi; An autonomous data gathering tool use to sense, collect and report back on a bee hive and hive surroundings.

It will feature;

Sensors:Hive internal temperature sensor, external temperature sensor, XYZ accelerometer and hive disassembly removal sensor.

Communications: The BeePi can connect via Wifi to a hub, Wifi to a master BeePi (collecting data from a whole apiary) or communicate via a 3G/4G dongle. Potential exists for a RFID based  ‘Check-In & Check-Out’ style system – useful if many people manage the hives in a particular area.

What will these sensors do?

Well, imagine your bee-hive(s) is located in an area where you suspect animals (or people) could knock the bee hive over. Using the accelerometer when the box is turned at an angle (for example being knocked over) the BeePi could send a message (via sms, pre-recorded message or email) with details about the hive, its location and at what time the event occurred.

Using an internal temperature sensor placed close to the cluster of the hive in the brood box it will give you an indication on the current status of your bees, including if the queen is laying and overall health of the hive. Typically happy brood = happy hive.

An external sensor placed close to the enterence the hive will give you an indication on if the bees are flying, as generally lower than 13 – 10c and they will stay inside and keep warm.

Hive disassembly sensor will alert you to when your hive is being dissembled, this could be handy if you believe someone is stealing from your hive and you wish to track times and events.

I believe that this is a valuable idea and project and will document my progress as I develop it further.

 

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With the free time from the bank holiday, not wanting to spend the whole weekend inside I decide to devote sometime to my BioGas project. Having considered the last run a success, apart from producing a lot of smoke the gas produced did eventually light, leading me to believe that the reactor was working and just needed to continue to warm up to operating temperature.

 I loaded the base full of charcol and get started again. Within minutes the base was hot and I loaded the chamber with wood pellets – sealing the top.

After 5 minutes the colour and quantity of the smoke changed and I used my blow torch to ignite the smoke.  Instantly I was presented with a hot yellow flame, while the flame was not able to maintain itself I believe this is due to the water content and lack of mixed air – a problem soon to be fixed.

Below is a ‘basic’ drawing of the setup

I have installed flare stacks at all the post-process points so that I can check the output of the gas – The last thing I want to do is do all this work and end up with something that doesnt ignite!

So project one complete, I can successfully make flamable gas from waste wood! Next step – Clean, Condense and find a use for the wood gas.

*UPDATE 14th October 2012*

Having now purchased my own air compressor (yay!) I was able to fire up the reactor again and do an extended test. Below is a snippit of video I was able to record:

Wood Gas Reactor

Project 2: Cleaning & Condensing

Fresh from the reactor the gas is still very hot and contains dissolved in the smoke a number of unhelpful substances – water being the biggest. In its highly energised state the gas moclules lack density and compressing them would be very difficult.

From my research I have found several methods of cooling hot gas (the top 2 being):

  • Heat Exchanger / Radiator
  • Water bubble tank

To keep things simple I opted to use a sealed water bubble tank. This is where the end of the outlet from the reactor is fed under water and the gasses are bubbled up through the water, both cooling the gas and seperating the water / water soluable substances at the same time. Keeping the water as cold as possible will hopfully force more of the waste componensts to seperate from the flamable gas cloud.

If needed a further process using hay as a filter medium can be slotted into place to absorb waste if needed – however I do not think this well be required if the ice water filter goes to plan.