Category Archives: Engineering

Nuclear Rockets, ​the Future of Space Propulsion?

images-2

(See my other Space and Propulsion related posts) – I came across the article “Earth To Mars In 100 Days? The Power Of Nuclear Rockets” today and wanted to share it.

 

 

The idea of a nuclear rocket engine was developed in the 1960s for NASA. The research was led by Werner von Braun and successfully tested in Nevada.

What is a nuclear thermal rocket?

A conventional chemical rocket carries combustible chemicals which are ignited, then the resulting gases flow out of a nozzle propelling the vehicle. In a nuclear rocket, a small marble size chunk of Uranium fuel undergoes fission. This energy released heats hydrogen to very high temperatures (nearly 2500 C). The hydrogen is then expelled from the vehicle in a nozzle like on chemical rockets. The difference is that nuclear propulsion is two to three times as efficient.  Tests were carried out starting in 1955 that have proven that this technique will work. Testing was discontinued in 1973.

Where are we Now? 

The original design required highly-enriched uranium. Current designs will most likely rely on low-enriched uranium.  This would make nuclear propulsion systems safer to work with. On May 22, 2019, the US Congress approved $125 million to fund new nuclear thermal propulsion development.

Another alternative being researched is using fusion instead of fission for propulsion. The Princeton Plasma Physics Laboratory is working on what they call the Direct Fusion Drive. Applied Fusion Systems is also at work on a fusion alternative.

Whether it is fission in the short term or fusion in the long term, the prospects for nuclear-powered rockets looks very positive. Read the full article for more details.

Celebrate National Robotics Week!

D3PuILrX4AA3Nn3

Robots – This week, actually it started yesterday, celebrates robotics in the US. Per the National Robotics Week website:

National Robotics Week (RoboWeek) is a series of grassroots events and activities during the month of April aimed at increasing public awareness of the strength and importance of the U.S. robotics industry and of the tremendous social and cultural impact that robotics will have on the future. Activities come in all shapes and sizes from a robot block party, university open house, or a robotics competition. The mission of RoboWeek is simple — to inspire students in STEM-related fields and to share the excitement of robotics with audiences of all ages. Celebrate RoboWeek by hosting an event in your community, sponsoring or attending a local event, or spreading the word on social media.

National Robotics Week was first celebrated in 2010 after university and industry leaders appealed to the Congressional Caucus on Robotics to create a “national roadmap” for robotics technology. On March 9, 2010, the U.S. House of Representatives passed resolution H.Res. 1055, officially designating the second full week in April as National Robotics Week.

Do You Really Know How to Learn?

51LIZ-CU64L._AC_UL436_Do you think you know how to best learn a subject? Even if you think you do you are probably wrong.

I came across the article “Learning how (and how not) to learn” which gave me some new insights into learning.

A team of Colorado State University Psychology Faculty has published the book “A Guide to Effective Studying and Learning” ($25 on Amazon) on how to learn. This is based upon their research. This book forms the basis for one of the most popular courses at Colorado State University.

So what are some of their findings?

  • learning styles exist, but no scientific evidence supports the popular myth that “people learn best according to their individual style”
  • spacing out shorter study sessions over time will improve learning outcomes
  • learning improves when you test yourself on the material
  • you will learn better if you elaborate on the material by forming associations

This is information all can apply, particularly engineers and others in the tech fields who are constantly having to update their knowledge. This is also something to share with High School and College students you know.

So Your iPhone XS Shows You Have 5G

Tech Tips – First, what is 5G? 5G stands for “Fifth Generation” and is the next generation of wireless communications. Most of our devices are operating on 4G at the moment. 5G will give us peak transmission speeds up to 20 Gb per second, far faster than what 4G provides. 5G will also provide reduced latency, energy savings, lower cost, higher system capacity, and massive device connectivity.

The first phase of 5G specifications in Release-15 is not scheduled to be released until April 2019, with the second phase (Release-16) scheduled for completion by April 2020. Even then it has to be approved by the International Telecommunication Union (ITU). While most carriers have test networks in place in selected locations, the worldwide commercial launch of 5G is not expected until 2020.

So how are AT&T customers seeing a “5GE” icon on their phones now? This is best attributed to some marketing efforts by AT&T. Their “5GE” is simply an enhanced version of the 4G LTE network you have been using. Users with 5GE capable phones may see faster performance in some areas. iPhone users must have iOS 12.2 or newer installed to be 5GE capable. For Android users, they need Android Pie or newer.

Only the iPhone XS and XS Max, as well any Android phone that uses 4×4 MIMO (multiple-input and multiple-output radio), have the hardware compatible with 5GE. No iPhones currently on the market are 5G compatible. 5G requires different hardware.

References

  1. Everything You Need to Know About 5G
  2. AT&T 5GE on iPhone and Android phones: What you need to know
  3. 5G

EM Drive Does Not Perform well in Tests

Propulsion – I have been watching the stories in the media on the EM Drive for a while now. If you are new to this, the EM Drive is a resonant cavity thruster. In simple terms, it is an electrically powered thruster that requires no fuel. It was proposed by Roger Shawyer in 2001. Most consider the EM Drive to be impossible as it defies currently known physics.

Previous tests of an EM Drive prototype by NASA showed some success. The EM Drive was subjected to more strict testing by a team at the Dresden University of Technology in Germany led by Martin Tajmar. They presented their results at the Aeronautics and Astronautics Association of France’s Space Propulsion conference on May 16, 2018. Their tests are not supportive of the claims made for the EM Drive.

The results presented by Tajmar is reviewed in the video above by Scott Manley. Tajmar and his team had not totally given up on the EM Drive at the time of their report. They plan further testing, but the prospect of this being the solution to propulsion hoped for is dim.

References:

  1. ‘Impossible’ EM drive doesn’t seem to work after all
  2. EmDrive: Not Quite (Yet?) the Answer to Space Travel

Boeing’s Autonomous Air Taxi Completes First Flight

Robots – Flying cars have been around in science fiction for many years. Now though we are on the verge of having them become part of our everyday lives. That said, don’t expect your next call for Lyft or Uber to be answered by a flying autonomous taxi.

The Boeing autonomous passenger air vehicle (PAV) shown above is just a prototype and so far it has only demonstrated the ability to take off, hover, and land. This is a 30-foot model is all electric and is designed to have a 50-mile range. Boeing NeXt is also working on a larger fully autonomous, electric cargo plane that will be able to carry up to 500 pounds.

Beyond the technical hurdles of building a flying car are the many regulatory issues that stand in their way. Needless to say, it will be a few years before we see these in our sky.

Boeing is not the only company working on flying cars. Among those interested in this market are Aston Martin, Rolls-Royce, Uber, and Toyota. These flying cars are intended to offer a transportation solution that will be able to carry passengers across urban centers where ground transportation would be slow or impractical.

The Story of Claude Shannon​ – The Father of Information Theory

511pvvcqgzl

Podcasts – I have mentioned the Internet History Podcast before. It is one of the podcasts that I subscribe and listen to on a regular basis. While the podcast “CLAUDE SHANNON, FATHER OF INFORMATION THEORY” was published back on May 27, 2018, I finally just got around to listening to it today and I wanted to share it.

This episode of the Internet History podcast deals with Claude Shannon. Specifically, it is an interview with authors Jimmy Sony and Rob Goodman. They have published the biography of Claude Shannon entitled “A Mind At Play, How Claude Shannon Invented the Information Age“. During the interview, they give a brief glimpse of Shannon’s life.

Shanon was a mathematician, electrical engineer, and cryptographer. he is most noted though for being the ‘father’ of information theory. His 1948 paper “A Mathematical Theory of Communication” laid the groundwork for modern digital communications. Just as important though was his work in digital circuit design theory. His Masters Thesis at MIT demonstrated that electrical applications of Boolean algebra could construct any logical numerical relationship. This is a foundation of modern digital computers.

In information theory, the Shannon–Hartley theorem gives the maximum rate at which information can be transmitted over a communications channel of a specified bandwidth in the presence of noise. This formula, which I saw repeatedly in graduate school, is:

screen shot 2019-01-24 at 7.06.40 pm

where (from the Wikipedia page)

 

  • C is the channel capacity in bits per second, a theoretical upper bound on the net bit rate (information rate, sometimes denoted I) excluding error-correction codes;
  • B is the bandwidth of the channel in hertz (passband bandwidth in case of a bandpass signal);
  • S is the average received signal power over the bandwidth (in case of a carrier-modulated passband transmission, often denoted C), measured in watts (or volts squared);
  • N is the average power of the noise and interference over the bandwidth, measured in watts (or volts squared); and
  • S/N is the signal-to-noise ratio (SNR) or the carrier-to-noise ratio (CNR) of the communication signal to the noise and interference at the receiver (expressed as a linear power ratio, not as logarithmic decibels).

If you are interested in computers, mathematics or engineering, you might want to dedicate an hour to listen to this podcast.

Robot ‘SpotMini’ Dances

Robots – I have continued to be amazed at what Boston Dynamics has been able to do with their robots. While this video of their SpotMini is not a technical marvel, it does show how flexible this robot is. In the video above it is performing to Uptown Funk by Mark Ronson and Bruno Mars.

The SpotMini is a quadruped, dog-like robot with a hand-like gripping extension. The SpotMini stands less than a meter (0.84 m) tall and weighs 25 kg (30 kg if you include the arm). The SpotMini is all-electric and can go for about 90 minutes on a charge, depending on what it is doing.  The SpotMini is the quietest robot produced so far by Boston Dynamics.

Central Texas IEEE Life Members Visit ATX Hackerspace

mgtvtt0bqpyto4lz89s%ga_thumb_346ca

IEEELocations – The Austin chapter of the IEEE (The Institute of Electrical and Electronic Engineers) Central Texas Section Life Members group (IEEE members who are at least 65 years old and who have been an active member of IEEE for at least 35 years) met last night at the ATX Hackerspace.

What is ATX Hackerspace? Per their website they are:

We are a collaborative industrial workshop full of people who love to learn and make things! ATX Hackerspace can be found at 9701 Dessau Road, Building 3, Suite 304, Austin TX 78754

We have over 8,000 square feet of space that is perfect for artists, designers, engineers, makers and hackers, fabbers, scientists, musicians, seminars and workshops, co-working, and a ton of other stuff. We’re the perfect place for any project that needs space, involves loud or messy equipment (woodworking, soldering, welding, painting), power (we have 120V, 240V, and 3-phase power), tools that are too expensive or large for your own workshop ( see our laser cutters, CNC mills, and 3D printers ) or meeting with collaborators.

More importantly, we are an established and ever-growing community. Imagine what we can do when we combine our skills, knowledge, ideas, tools, and materials… or see for yourself at our next Open House, every Tuesday evening from 6-10pm.

We’re hackers (thoroughly defined here), which means we create things and we put things together in new and innovative ways. ATX Hackerspace is dedicated to encouraging and promoting technical, scientific, and artistic skills through projects, collaboration, and education by all legal means.

After a brief meeting, we were led on a tour of the ATX Hackerspace facility.

img_0542

The first stop was the room with their 3D printers. Unfortunately, some of the folks taking the tour blocked the larger printer in this photo. It is located against the back wall to the right. Smaller printers are on the table to my right out of the photo.

img_0543

In addition to the 3D printers, they have a small electronics lab space.

They have two relatively large laser cutters.

Their largest ‘maker space’ is their wood shop. Not shown is their welding area and car shop. The auto area is near the yellow box in the larger of the images above. The welding area is behind the red-curtained portion of the space.

ATX Hackerspace has a number of tools available. You can see the complete list of their tools-resources.

For a $75 fee with 24/7 access to the building, this looks like an inexpensive and well-tooled facility to take your projects from design to reality.


See my other articles about Food & Locations