Learning About The Space Shuttle From the People Who Built it.

It has been a while since I posted last. I just finished watching a set of lectures from MIT called Aircraft Systems Engineering from the Fall 2005 semester. The purpose of the course is take a look at issues in aircraft design in terms of subsystems, integration and management.

This particular class examined the issues associated with the design of the Space Shuttle with talks being given by people who were actually involved with the design and operation of the shuttle. In addition to covering technical issues associated with the shuttle, a lot of information is provided about the politics, the tradeoffs in design and personal opinions.

I know that after having watched these lectures I looked at the preparation, launch and recovery of the recent Atlantis mission in an entirely different light.

So You Wanna Build A Rocket?

Time to have a little fun and take a look at a cool scifi website. The site is called Atomic Rockets. It looks at some of the issues in designing a spaceship for that science fiction novel you keep meaning to write. The goal is to try to minimize the amount of handwavium you have to add to get your rocket to work.

In addition to covering basic physics issues, Atomic Rockets looks into what kind of weapons and tactics you will need to defeat your arch villain. Your rocket engine is the biggest gun you have! The site also looks at galactic politics. If you want to build that galactic empire, how are you going to control it?

While the technical information is great, what makes this site really stand out is the fantastic artwork included from the golden age of science fiction. Lots of great artwork is included from the covers of several science fiction magazines and books. I probably spend just as much time zooming up the images with my Image Zoom extension to enjoy them as I spend reading the site.

The site is always being updated so be sure to visit it every few months to see what has been added.

The History of Wind Tunnels At NASA

I came across this excellent document on NASA’s website. It gives the history of wind tunnels starting with the first experiments in the 1800’s, through the time of NACA and finally NASA.

This history covers some of the difficulties encountered such as air liquifying as the pressure changes in the tunnel. The document also covers how wind tunnels were used to simulate the braking maneuvers for satellites to go into orbit around Mars and Saturn.

If you take the time to read this document it is also worth while to look up some of these sites using Google Maps to get a feel for what these structures look like and their size.

Introduction to General Astronomy with Alex Filippenko

If you are reading this page then you probably have watched your share of shows on PBS or the Discovery Channel about various aspects of astronomy. Now, courtesy of UC Berkeley, you can watch an entire semester of Introduction to General Astronomy and get an introduction to everything from Keplers Laws and the origin of the Solar System to what is Dark Matter.

I watched the lectures from the Fall 2004 semester. There are also lectures for the Fall 2005 semester. However I recommend watching lectures for the most recent semester because astronomy is a very dynamic field. The status of Pluto as a planet being an example of a recent change.

Dr. Alex Filippenko is the instructor and you may even recognize him giving comments in some of the documentaries you see. Dr. Filippenko is a very enthusiastic and energetic instructor. You can tell he has a great love of teaching and of astronomy. If you have any interest in astronomy, once you start watching his lectures you will not want to stop.

Sending Cubesats to the Moon and Mars

Cubesats are small satellites usually built by small groups that can be sent into orbit for a relatively low cost of 50-100 thousand dollars. They are 10cm on each side and a weight limit of 1 kilogram. There are plenty of websites (also here) that have already discussed this so I will not bore you with all the details.

One thing I did wonder about was what would it take to send one to the moon or even Mars. Well it looks like someone else is giving this some thought as well. They even think about what it would take to land one on the moon!

The talk is called How Far Can A Cubesat Go by Flemming Hansen at the Danish Nation Space center. This paper looks like it was given as part of a talk at the Space Technology Conference at Aalborg University on April 7, 2005.

The paper goes into a lot of detail and considers issues such as total mass, power, heat loads, delta v requirements, etc. Fuel requirements seem to be the biggest issue. However the design uses chemical fuels. I would think if a small ion/plasma engine were added, the improved specific impulse would reduce the fuel requirements.

I think the prospect of doing even basic exploration using thousands of small satellites is quite exciting. There is a place for the really big satellites that are currently launched, but I think a shotgun approach would allow us to find many more interesting opportunities in our solar system. Even if all that was carried was a camera it would give us a chance to explore locations that would take decades to see otherwise.

Hacking Inkjets and Microarrayers

How often have you wanted to hack around with an inkjet. The biggest problem is finding technical information on how to drive the inkjet cartridge itself. One option is to use the inkjet cartridge from parallax.com, which gives you 96dpi.

However the nice people at bioinformatics.org provide an even better option. In the course of designing their own Oligonucleotide Synthesizer And Microarrayer, they managed to build their own custom driver board for the inkjet cartridge of an Epson Stylus Photo 700. This has a resolution of 1440×720 dpi.

Full details can be found at http://bioinformatics.org/pogo. Look at the documents User Manual Chapter 1 and Chapter 2 for details on how the inkjet cartridge is used.

So nothing should be stopping you from building that large format inkjet printer or a direct to pcb printer.

Learn about MEMS

Universities putting lecture webcasts online is an example of the internet at its best. I have watched several classes worth of lectures already and I will occasionally list ones that I found particularly interesting.

UC Berkeley has several years of lectures and events archived at the webcast.berkeley.edu site.

The first set of lectures I watched online was Dr. Chris Pister’s
Introduction to MEMS Design. This is a full semester of lectures on the engineering of MEMS devices. It helps to have have some science background. However if you do not have a strong science background, the first few lectures gives a nice overview of MEMS and Dr Pister shows some nice gee wiz pictures of various devices.

Enjoy!

Maskless Lithography with a Projector and a Microscope

Todays paper describes how a group of undergraduates put together a maskless photolithography system using a trinocular microscope and an off the shelf video projector. The total system cost is a bit expensive, but I can see this method being more commonly used as the price of video projectors goes down and resolutions go up.

This paper can be found with a google search or going to aip.org.

So I present

A maskless photolithographic prototyping system using a low-cost
consumer projector and a microscope
J. David Musgraves, Brett T. Close, and David M. Tanenbauma

Abstract

Lithographic processing has been the key technology responsible for the rapid advances in microelectronics, but is typically not accessible to undergraduates. We have developed a maskless photolithographic system that can be assembled from a consumer projector and a trinocular microscope. This system allows students to design and print custom patterns into photoresist in less than 30 min, without using a clean room, a mask facility, or a chrome-etch bath. Students can create and evaluate patterns, make changes to their design, or add additional layers of aligned patterns in a single laboratory session. The rapid turnaround time and low cost of ownership is useful for low-resolution (~10um) prototyping. Photoresist is spun in a modified food processor and baked on a standard hot plate. Mating pieces were machined from aluminum. Only the digital light processing projector and food processor are modified, so the microscope, camera, and computer need not be dedicated to the system. The entire system can be assembled for less than $5000.

Play Optics with LEGO

Welcome to the first post of The Tech Buffet. This will highlight a wide variety of scientific and technical websites, articles and scientific papers that I have found out on the web.

So the first paper I will list is

Play Optics with LEGO Quercioli, Franco; Tiribilli, Bruno; Mannoni, Andrea; Acciai, S.
The abstract

The basic elements of a fairly complete optomechanical kit based on the use of LEGO^TM is presented. Through a careful exploitation of the many standard LEGO elements, and adding a few new simple components made of plexiglass, we demonstrate that almost all of the mechanical parts of an optical setup can be built with little effort and at an extremely reduced cost. Several systems and experiments are presented, mainly in the fields of optical filtering and interferometry, to show that the proposed mountings are perfectly suitable for didactic purposes, and can often be employed even in more demanding scientific applications.