Over the last summer break I was lucky enough to work with CRCMining as one of their vacation work students. I was assigned to one of the project groups whose task was to design an electronic spark tester.
When I first arrived I was given the task of reading through all the literature that had been reviewed for the project. I had been given a few documents before I started, but I was thrown in the deep end and now had 20+ articles to read. This was my first taste of German English, and some of the articles contained not just interesting information but interesting grammar.
From here I was asked to go and find a chip that would fulfil the requirements for the spark tester. Over the next couple of days I became very familiar with many of the manufactures websites as I trawled through their catalogues looking for something that was suitable. 1000 datasheets later I’d narrowed the list down to 197 of which 20 looked promising.
As I must have shown some promise with datasheets, I was then given the a very similar task to find another chip. After another day or two and a few new manufactures another spreadsheet was created.
Up next was the construction of the testing apparatus for some of the devices that had been previously purchased. In the past I had only prototyped using breadboards, veroboard or actual PCB’s. One of the electrical engineers I was working under, Deryck, showed me a great way of rapid prototyping that involved copper backed acrylic and copper tape. I designed the circuits in Altium, printed them off and cut them into the copper tape which had been glued onto the acrylic.
Practice makes perfect, and after 4 boards I think I got the hang of it. After drilling all the necessary holes and soldering the components on came the fun part of mounting the board with all its connectors into the box. After a day or two of fiddling around and some very close calls with soldering iron burns the boxes were finished.
Now that we had devices to test, we needed to figure out what to do with them. We sat down and discussed what testing the devices would need to undergo so that their characteristics could be determined to see if they were suitable for the spark tester. I wrote the testing document and we reviewed it over the next couple of weeks.
With the devices built and the testing document written all that was needed was the testing apparatus. This produced its own set of problems such as the required power rating and how we were going to build them, but in the end we had it all knuckled down.
After a couple of weeks of work, I finally sat down to start testing the devices. Then weird stuff started happening. After thinking about this for the last couple of weeks, I thought I would know what was going to happen when we started testing, which was that when we turned on the device the voltage would stay constant. Instead, when we turned the device on, the voltage constantly dropped. After having a bit of a talk with the electrical engineers that I was working under we think we know why.
After playing around with the devices some more and everyone having a look, it was decided to modify the devices the end results of which was very similar to the starting test boxes but had better performance. Using these new and improved test boxes I finally started getting some data.
In between all this there were a couple of trips to Simtars-the mining industry's safety testing body. Simtars gave me insight into how verification is completed in industry, which is something I was not expecting to gain from my time here.
Another little project I had was to convert around a 600 Oscilloscope outputs into the proper format. I had a crack at this using python, but in the end I had to call in some specialist help in the form of a mate of mine from uni. I was pretty close, but as with programming you can be close but you’re still a million miles away from the solution.
From my time at CRCMining I’ve learnt a hell of a lot. One of the biggest is simply how much I do not know. It’s been impressive at how quickly the electrical engineers that I was working under, Eddie, Rajiv and Deryck can pull facts and figures out of their heads, and to put this information to use to solve problems in minutes that would have taken me days if not weeks solve. It’s rather intimidating and impressive.
The main reason that I took this vacation works was to see how research is conducted in industry and to see what process and structures are used in a research project. I got to see this and much more in my time at CRCMining and it’s been a great experience. Seeing that research is very much a team oriented task and how the interaction of the team leads to a much more thorough and productive project was something that I suspected but actually seeing just how much it can add to a project was really good to see.
I have also seen one of the perils of research if you would call it that. When I was starting to test the devices I was short a couple of banana leads. I went to Eddie to see if there were any laying around and in the conversation Eddie realised that we needed to look into how our cables and leads would function at high frequencies, the effect of the skin effect on out experiments and how it must be taken into consideration when choosing the wire and how we could use litz wire. Therein followed a half day of work looking for litz wire suppliers, skin effect depths, how to wind litz wire and finally creating some banana leads that might be called a close cousin to litz wire. And all this started from simply asking if there were a couple of banana leads around the place.
I’ve also learnt the value of having contacts when you’re working – both within industry and amongst your peers. I had to call on one of my mates from uni to help me with a the python programming problem that I was having. I wouldn’t have been able to figure out the problem this side of July without his help: a big shout out goes to Jeremy Herbert.
Finally, I had a great time at CRCMining. Everyone has made me feel welcome and accepted and has helped me along the way. The great atmosphere at CRCMining is warm and inviting and everyone is treated as a equal. The xmas party and bbq lunch were heaps of fun. I’d really like to thank CRCMining for the opportunity that they gave me in taking me on as a vacation student as I’ve learnt so much that I doubt that I could learn anywhere else. I would highly recommend them to any other electrical engineers looking for vacation work.
Jack.
