Thursday, September 13, 2012

September Meeting

We're starting off our club a little differently this year. In addition to providing support for the kids as they work on their projects, we are all going to do the same project together. Doug (holding the magazine, above) has offered to guide the kids through making their own RC stunt plane as featured in Make: 30. Jim will provide workshop space for any soldering, and no doubt we will rely on both men's expertise and experience.

We'll plan to post the progress of the builds to this space.



Monday, September 3, 2012

Working at Lawrence Berkeley Labs


by Doug Van Camp

This last week I started a new job at Lawrence Berkeley Labs. It is pretty much an ideal job for a Maker type person. Overall, LBL is practically a maker’s paradise, considering the amazing array of stuff that they make and work on there. Their projects run the gamut from biology to energy.

Incidentally, they are having an Open House October 13 that is open to the public. I highly recommend you all go. See the details at: http://www.lbl.gov/openhouse/

My first major task will be to help remove one experiment from a beam line of their cyclotron and install a new experiment in its place. Part of the installation process involves designing many of the components used in the system and then fabricating them; primarily by machining the parts using mills and lathes. Some welding maybe involved as well.

The new experiment we are installing is part of the development work of the next generation of micro-processors and is being paid for by a consortium of companies such as Intel. As microprocessors, become more powerful and densely packed, their components become smaller and smaller; to the point that, the circuit paths may only be a few atoms wide. Consequently, new techniques need to be developed to reliably build the new processors. The new experiment is exploring ways to make those circuits smaller and to check that they are built properly. The specific process we are working with is called X-Ray Lithography. That process has been around for decades, we are just refining it so the details are finer and finer.

Above, I mentioned ‘from a beam line of their cyclotron’ and that probably needs some explanation. Mind you all the explanations here are very general. I highly encourage you to do your own deeper research and/or to ask me questions. Anyway, the general concept of the cyclotron is to accelerate electrons to speeds near light speed by using very strong electromagnetic fields and forcing the electrons into a spiral path where they start at relatively slow speeds in the center and then move outward as they speed up.

Keeping the electrons spinning inside the cyclotron at near light speed requires enormous magnetic fields and complex controls. After all, like all things in motion, electrons would move in a straight line unless acted on by some force. So there are many electro-magnets placed around the circumference of the cyclotron to help ‘steer’ the electrons on the desired path.

Now every time the electron is ‘steered’ in this system, energy is added to the electron and to compensate for that additional energy, the laws of physics say something has to happen. Under the conditions in the cyclotron, that something is that the electron emits a packet of energy in the form of a photon, otherwise known as light. This light is not visible and is, in fact, and X-ray. But from a physics stand point, visible light and x-rays are just different points on the electromagnetic wave scale and the only differences between the two are their wave length and energy level.

So essentially, at every magnet around the ring of the cyclotron there is a ‘window’ or port that allows, and directs, the x-rays out into a large number of different experiments. Each of these ports is referred to as a beam line. Each beam line is directed thru a series of pipes, valves, shutters, chambers, mirrors, windows and other paraphernalia to perform whatever task is desired for a particular experiment.

Below are a few photos from the Lawrence Berkeley labs property, including some from inside the Cyclotron building.
Somebody built a sterling engine to run on top of the coffee maker in our break room.
The building on the left with the domed roof is where the cyclotron is located. The brown building to the right of the domed building is where my workspace is.
In the distance is the SF Bay including both the Bay bridge and the Golden Gate Bridge (although they are very difficult to see in the photo).
Here is some of the type of equipment that I will be working on.
This is part of the top of the cyclotron assembly. The big grey thing above was a huge electromagnet.
Here are a few of the many, many racks of equipment that are part of the facility.
Now that electromagnet is a support for the crane. My coworker is standing there to give some scale to the size.
That thing in the back ground is a machine used for winding electromagnets.