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.

 

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.

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