Friday, September 7, 2012

Lightning Sensor


I have been wanting to catch lightning for some time, and with the purchase of the CameraAxe, I thought my dreams had come true.
Think again, I discover that my Olympus E520 has a shutter lag of 300ms, miles too slow.
So I looked towards my other camera, the Panasonic FZ50, which is said to have a very quick response time, still more problems, I find that it has an entirely different remote triggering system than other cameras. It works on resistances, and could not be triggered via the CameraAxe.
The only way out of this was to build a unit that would give me what I am after. So I decided to build one around the Arduino Microcontroller,  I set about designing a board, it had two reed relays, one for focus, the other the shutter, though I ended up not needing the focus, as I used manual settings.
I have two Camera/ Flash ports, one for the Panasonic, the other for flash and other cameras, though having the CameraAxe I doubt I will use this trigger much. There are  two sensor ports, one set for greater than the threshold the other for less than, also a dedicated laser port. Three pots handle the two thresholds and the delay settings.
Not knowing anything of programming made it somewhat difficult, but finally I got it up and running. Now we come to the other problem, no lightning, plenty of rain as seen by the dreadful flooding.
So in the mean time I am working on a multi-laser trigger, so I can capture birds flying to my feeder. I have made and tested a board, consisting of a 5volt regulated power circuit to run the lasers independent of  the Arduino Camera trigger,(or the Axe) with a Tip120 transistor to act as a switch, triggered via the Arduino unit.My main reason for this, with each laser pulling between 15 and 20 ma, this would have put a great deal of pressure on the Analog pins, I plan to use 5 laser modules, my main concern is how to wire the corresponding light sensors. I tried daisy chaining them, that didn’t  work to well,  In the end  I decided to try an AND Gate, also not too flash, getting the wrong signals at the output.
after trying several other Gate’s, without much success, I searched the net and asked many questions , and finally found I needed a Nand gate, with a hex inverter between each photo transistor and the Gate, with another inverter at the output, This worked great on my Arduino test setup, but I found that using a NOR GATE did the same job, and only used one IC, so this is the way I have gone.
The laser unit having been built and working meant having two separate units to contend with, so as I was having to make a board for the sensors, I decided to combine the two together.
Below is  the diagram of how I built it, because of the shutter lag I will have to use the FZ50 camera.

multi-laser
The laser and sensor rods are removable, so they can be used for other things, the support frame can fold flat for easy storage.The sensor And laser poles have the connecting sockets built in.
I run this from a 12v 4amp sealed lead acid  battery.

Monday, May 30, 2011

Air Canon

I am writing this up because of a request from Maurice to do so.

After reading Maurice’s article on the Air Canon he built, I was sure there was a way of building one that would be able to fire via an electronic system.

So I went on a scavenger  a hunt in my Sons shed and what I found was a 12v Solenoid, an old Butane Gas  blow torch, and because he loves his Old man, I had little trouble in removing them from his possessions.

Putting it all together was fairly simple, I use a piece of acrylic sheet for the base plate, this proved a little to flexible, so I glued a piece of aluminium channel on the underside to stiffen it up. This also acted as a channel to run the cables from the Projectile sensor to the CameraAxe.

I Bolted the solenoid to the base, fitting the tank was a bit of a problem, but I ended up forming a bracket from some aluminium 2mm X 25mm Bar (1/8 X 1inch ). glued this to the tank, and drilled the solenoid cover and the tank to it.

The gas tank has a valve in the input, this I drilled out with a 6mm drill, I also enlarged the opening in the trigger fitting, the trigger itself was sawn off, I found an old flexible gas pipe and cut a portion long enough for my needs leaving a fitting on one end, the other end was forced onto the gas fitting, and retained with a hose clamp, I now needed a means of pressurizing the tank, for this I use a valve from and old bike inner tube which was forced into where I had removed the gas tap.

The barrel was a length of aluminium tube bought from the local hardware, this was flared at one end, though this was not really necessary, as I could have quite easily glued it in place.

The hardware finished I had to come up with a means of firing it, what I was looking at was a means to trigger the camera as well as the solenoid.

Thanks to Maurice and his great articles I had been playing with the Arduino for a while, so decided this was the way to go. I designed and made a shield board to do this, the Electronics was simple enough, but having no knowledge of programming made things a little more difficult, but again thanks to Maurice’s articles, I gleaned enough to get it running.

Now came the test, I pumped it up using a hand pump quite hard work I might tell you, and it worked first time much to my surprize, though the pressure was very low, I got the use of a compressor, and much to my delight it built up 100psi very easily, this is when I discovered that the solenoid would not trigger above 60psi, it worked to a degree, but not how I had hoped for.

I found a solenoid on ebay that would fire up to 140psi and at a reasonable price $25.00. http://cgi.ebay.com.au/ws/eBayISAPI.dll?ViewItem&item=130502647805 , There are many different voltages and pipe sizes available, I chose the 3/8 model.

When it arrived I found it to be a touch larger than the previous model also the fittings were slightly different, so had to alter the design a touch, The pipe fitting can be got at your local plumbing supplies.

I wasn’t able to fit the tank to the solenoid, and because I was afraid of damaging the tank if I tried to remove the bracket I decided to mount it to the side, just a matter of drilling a couple of holes.

Again came testing time, Would it give a trigger at 100psi, !!!YES!!! and the first result is below. I am looking at changing  the electronics,  I designed a new circuit board which now incorporates the Arduino chip, and all necessary sensors, I was looking at triggering this via a remote control, but so far haven’t been able to get enough info about it,  anyone with any ideas on this, your help  would be much appreciated, please leave a comment. I will stay with what I have until I can see if it is worth the trouble

What I like about  this design is I have plenty of scope where missiles are concerned, so far I have tried ball bearings, pencil stubs and I have made some from the nozzles from silicon tubes, and the screw driver bits all work well.

Why did I decide to make this, well simply put, the gun laws here are very tight, to much of a hassle to get a licence. Probably illegal, but not dangerous to anyone but me, could you imagine me hauling a compressor around, I think not.  

I am sure there are many more items to be found that would do just as well to build this, But please be careful, make sure you work safe, and don’t hold me responsible for any injuries or damage that may occur while using it. You make it at your own risk.OLYMPUS DIGITAL CAMERA

Layout of the circuit board That I will probably end up using.

Air Canon

OLYMPUS DIGITAL CAMERA

P1080132

I prefer the look of version 1 , but version 2 works much better because of the higher pressure allowed by  the solenoid.

If anyone wishes further info please email me at erniehatt@yahoo.com.au or leave a comment here.

A few safety ideas.

1 load the missile,2 set up the target, 3 do your CameraAxe setup, all these things before pressurizing the Airgun. hope this is of some use.

Wednesday, December 8, 2010

Reflector Beam

Reflector beams.
I thought about this for some time, toying with different ways to put it together, and decided that given the materials on hand this was the way to go.
First I had to make the initial frame which was pretty straight forward, except for making sure that the top and bottom which held the mirrors was parallel, to do this I made the top on a swivel.
That sorted, the next area I looked at was the laser, I needed some way to be able to adjust it for angle and align it centrally, for this I found a piece of electrical conduit pipe with a socket on the end, I cut two 1/4 inch pieces from the socket, and a suitable length of the pipe, slipping the socket pieces onto the end, this at first was a little tight, but rubbing the inside with some sandpaper eased it nicely. I drilled a hole in the centre of the pipe to fit the laser, which was held in place with a little super glue.
The placement of the detector, depends on where the beam end's. The circuit  was  that used in the Crossbeam article.
Adding power to the laser and trying to align the beams proved to be much more difficult than I had imagined, instead of getting a nice line of laser dots I got an arc, but by lifting the opposite end to the laser did straighten the dots to a useful degree, but the dots were not an equal distance apart. This was quite a puzzle to me at first, but on doing some research, I found out that the main problem was caused by refraction, as far as I could make out, the first  reflection bounced of the glass surface, another passing through the glass got refracted, was then reflected by the mirror surface and refracted again, this happened over and over again.
I had heard about surface mirrors, so again made a search of the internet, and found that someone making Spirographs had found a method of removing the protective coating on the back of the mirrors. So I tried this method and it worked perfect on both glass and Acrylic mirrors.

Requirements.

1. Mirrored Acrylic, or Glass Mirror.
2. "Mötsenböcker’s Lift off 5 Latex Based Paint Remover" . This is the one I found here in Australia.
Mötsenböcker’s doesn't damage the mirror surface or the acrylic at all. You have to let it sit for awhile though, about 5 - 30 minutes. You shouldn't have to "rub" to get the paint off, if you let it sit long enough, the paint will just float off.
3. Once the paint cracks up, remove it from the lift off and rinse under running tap. the liquid can be returned to it's container for  reuse.
4. let it Dry, then polish lightly with soft cloth to remove any water smear.
Another product that works equally well is "Winning  Colors Stain Remover". ("not found here in Australia").
Both are available in the USA.
Ok, here's the big question ("Did it work ?") Well yes in the first instance, to a fashion that is, but not how I wished as explained above, but since using the surface mirror idea, things have changed.
I still got the arc, but with a bit of adjustment of the Laser itself, it worked fine, it does take some fiddling but the end result is pretty good, I managed to get the gapes between the beam dots to about 1/2 inch apart.
Not sure how this would work on a larger scale, it may need to use two laser’s.
Being as my Olympus E520 camera has a shutter lag of 500ms I can’t do any real trials outdoors, But I am in the process of making a unit via an Arduino that will allow me to use the Panasonic FZ50  which they tell me is pretty quick, time will tell.
Reflected beam
Reflector beam
This photo was taken before I changed the mirrorsOLYMPUS DIGITAL CAMERAOLYMPUS DIGITAL CAMERA

Here are a couple of examples taken in the dark via flash, will try to add some real-time camera shots later

Thursday, December 2, 2010

Crossbeam

 

Crossbeam Sensor.
As you can see form the images below, the frame is made from plastic water pipe, I tried electrical conduit but found it to be too flexible. Using pipe for frames is of course  not new, so I will not take any credit for the idea, also the crossbeam was also made by someone else as well, but where mine differs is I have used lasers instead of infra red, because the lasers will work over larger distances, and are easier to align. also the original idea had the wire affixed to the exterior of the frame, held in place with tape. Though my idea takes a little longer to construct, I believe it to be much neater and more efficient.
Size of the frame doesn't matter to much, it can be as small as two inches or large enough to catch larger animals walking through it. Though a larger size I would think, would need a bigger diameter pipe.
Start by cutting four equal lengths of pipe, mark the centre's and drill holes in two of them to suit the laser modules you are using, in the other two drill hole to suit which ever detector you plan on using, I chose Photo resisters (LDR"s) simply because I had them on hand, but phototransistor's will work as well, maybe better. Directly behind these holes I made a cut out  with a dremel type tool so as to be able to get at the circuitry, not that there is much involved in mine, it depends on the voltage requirements  of the laser modules to be used.
Wire up the circuitry and thread it though the pipe and corners, measure the distance from the centre to the bends making sure they are all equal, once it is all in place line up the lasers and detectors, by twisting the pipes, and tweaking the components, adding power to the laser's will be a great help, once aligned put a little super glue against them, and some hot glue to hold the pipes in place. Attach inline 3.5 sockets to the leads and where done.
I wonder if we could parallel more lasers and LDR's, I might give it a try.
I had tried a crossbeam before, using a none microcontroller unit, and found that to trigger it you had to break both beams at the same moment, but with this one it doesn't matter which beam you break it will fire, I thought at first that this was because the Camera Axe was  turning off the lasers, but on testing this with my Arduino Prototyping setup, i t performed in the same way, and it is not set to turn off the laser's.
I took a couple of pics with it, I just threw the model through the beam, I know it is not very well focused, but it proved it worked. I set a 70ms delay. this would depend on how fast the subject was moving, I haven't tried it, but should imagine that dropping a heavier object through the beam  would increase the speed, thus the delay. My object at 70ms only travelled about 4-5 inches.
On reflection, as this stands it would be very hit and miss for insects, there is too much space around the beams, But if you were to make one on a much smaller scale say 2 inches square, and set it close to a flower then maybe it would be ok.
I think my next project would be much better.
 
 
OLYMPUS DIGITAL CAMERA OLYMPUS DIGITAL CAMERA

crossbeam2fin

 

Crossbeam

 

I haven't as yet tried it in real life situation, it would  more than likely take much
more trial and error in setting up, to allow for shutter lag etc..
Link to Lasers below.
https://sslrelay.com/odicforce.com/shop/article_OFL85/New-Micro-Red-Laser-Module---5-Pack.html?sessid=C9hMotrTiiwudszXISr2qYXzizv2Cb4Tv5wjeRvhzYQqUKIGLGOmpt4NK4fyjM8I&shop_param=cid%3D13%26aid%3DOFL85%26
Hope someone will find this useful.   Ernie

Monday, November 8, 2010

Getting started

Nov 09 2010.

About 12 months ago I found some info on High Speed Photography, and decided that I would like to get into this.
I tried some electronic circuits, which worked quite well, but each module was a seperate item, and I found setting delays was quite a pain.
So I made a search , and found DreamingRobots.com where the owner Maurice Ribble had done a lot of work with the Arduino Microcontroller board, there were a lot of different projects to wet ones appetite.
Having played around with the Arduino, I decided this was what I was looking for.
With a lot of breadboarding I finally came up with three sensors, Sound, Lightning, and photogate, all working as one unit with the Arduino. I designed and made a circuit board to handle all three sensors each with there own input, and outputs for three Flash units or camera. The threshholds and delays were set by potentiometers.
My biggest problem was the programing side of the project, but with examples on Maurice Ribbles site, and, much trial and error I got it all working, be it some what touchy.
In the meantime Maurice developed a unit ( The Camera AXE ) which left mine for dead, I could never dream of adding the sophistication of his software, so I purchased one along with some of his sensors. Now I have developed some sensors of my own, which I will be writting up here, very soon, along with pictures, I hope you find them of use.