Another micromirror project update

Added the last polysilicon layer to mount the mirror on.  Some minor changes have been made since uploading:

Project 1 for MEMS: Micromirror: Update

We have a 3d model! Now to load it in ANSYS!

How amazing is Nanotechnology?

Breakthrough: This metal is almost as light as air

Ultralight materials are usually made up of chaotic structures, like the bubbles in aerogel. But this metal is created out of a solid, repeating structure. It's called an ultralight metallic microlattice, and it's produced in an intriguing way. The method involves using a liquid photopolymer which solidifies when hit by ultraviolet radiation. Scientists shine light on the liquid through a pattern. Only the exposed bits of the liquid become solid, creating a lattice-work scaffold, which is then coated with nickel-phosphorous. Once the photopolymer is etched away, all that is left is a 3D, hollow lattice of metal which is more air than anything else.

Video in action

Project 1 for MEMS: Micromirror

The assignment:

The objective of this project is to design a surface machining fabrication lay out for a MEMS torsional micromirror using the SANDIA SUMMiT V fabrication process and design tools.

Using the SANDIA SUMMiT V design and visualization tools, design the surface micromachning lay out for the torsional micromirror shown in the attached Power Point file. The micromirror should contain etch holes, dimples…etc as necessary. The accompanying Power point file (located on the S-drive) displays the mirror’s geometry and needed information.

My early model: 

Pictures from last week's Nanotechnology lab

This semester I'm taking an intro course for MEMS and Nanotechnology as a part of the MS/NT minor.  Here are some pictures taken from a Scanning Electron Microscope (SEM) of a bug and a MEMS chip

 
As a comparison, the diameter of a human hair varies from 17 to 181 µm

Ever wonder why HP/Torque fall off after a cetain RPM?

You're not the only one...
In short, from the first reply of that thread...

The relation between torque, power and angular speed is



Power falls off below a peak located at high engine speed, because less fuel/air (energy source) is brought in and burned per second. If that were the only factor, then power output would be proportional to angular speed



and torque would remain constant down to idle. In fact passenger car engines have a fairly broad and flat torque curve. See the curves at, e.g.
http://en.wikipedia.org/wiki/Power_band

However engine efficiency drops with at low speeds since combustion chamber shape, bore/stroke ratio, manifold runner shape and length, valve lift and intake/exhaust valve overlap, to name just a few factors, are tuned for best performance at higher engine speeds. Thus torque eventually falls. In racing cars, the tuning is "peakier," that is, they produce far more peak power but only over a narrow RPM range. As you might expect, the torque curve isn't as flat in this case, and it falls off more rapidly. See Fig. 3 here
http://www.corvetteactioncenter.com/tech/hp_torque.html

Vehicles that are optimized for very high torque at very low vehicle speed either have no high end to speak of (road graders, bulldozers) or, if they need both, use different systems (diesel-electric locomotives).

Update 12/13/10: revised picture links

Nanotechnology, what can't it do?

Link

The storage and generation of electricity is a hotbed of scientific study around the world. New and improved methods of storing electricity have a myriad of potential uses from phones and laptops that run longer to new electric vehicles with much greater driving range.

At the center of much of the research in the storage and generation of power in batteries and other devices are carbon nanotubes. The carbon nanotube has been studied for decades and new advances over the last few years have made the nanotubes easier to produce and have offered breakthroughs in the use of carbon nanotubes.