Today in History – February 1, 1972 – First scientific hand-held calculator, the HP-35, introduced for $395. I was an undergraduate in engineering when the HP-35 was released. I couldn’t afford to buy one and stuck with my slide rule. But the next year, I gave in and bought the next model, the HP-45 and it was well worth the money at the time. The calculators were easy to use, portable and reliable. The market responded by developing cheaper calculators, while Hewlett Packard kept the cost high and increased the functionality.

Check out the Engineering Pathway’s educational resources on the electronic calculators and history of computing. For more educational resources, see our electrical engineering education and computer engineering education community pages. The Engineering Pathway also hosts Engineering Education communities in all ABET-accredited disciplines.

Today in History – January 28, 1986 – Space Shuttle Challenger explodes after launch, killing the entire crew. American’s stared in shock at their televisions watching the Challenger accident in full motion video. The 35th Challenger’s flight had been previously scheduled for January 22, but delayed because of bad weather, high winds and icicles on the launch apparatus. Never had there been a launch approved in freezing weather conditions, but NASA had assured the public that the conditions were safe. They were anxious to launch due to economic considerations and scheduling backlogs. Political pressure has been suggested as well due to NASA’s heavy publicizing of Christa McAuliffe as the first school teacher in space. She had been selected under a highly competitive process from among 10,000 entries for the opportunity. The Challenger disaster was a severe blow to the American space program, bringing manned flights to a halt for many years. It was also a blow to the American public who had come to think of the Space Shuttle as an important symbol of national identify.

Speaking before the launch, Christa McAuliffe said: “One of the things I hope to bring back into the classroom is to make that connection with the students that they too are part of history, the space program belongs to them and to try to bring them up with the space age.”

Morton-Thiokol, one of the contractors for the Solid Rocket Motor was convinced that the cold weather would cause problems and had briefed NASA about their concerns. Two engineers, Robert Ebeling and Roger Boisjoly had previously urged a redesign on the booster rockets due to O-ring erosion in the booster field joints. The lowest temperature experienced by the O-rings in any previous mission was 53°F in the January 24, 1985 flight; the temperature predicted for Florida on January 28th was much lower, in the low 20′s °F.

The Rogers commission confirmed the cause of the Challenger disaster explosion to have been caused by a leak through the faulty O-ring seal in one of the solid rocket boosters. According to testimony by Morton-Thiokol engineer Boisjoly, management put pressure on the engineers to OK the launch saying: “Take off your engineering hat and put on your management hat.” The recommendation was reversed, discounting the concern about the O-rings as being “inconclusive” and launch was recommended, “based on their engineering assessment”, even though the engineers had no part in this recommendation. In spite of concerns expressed by others, NASA managers decided to approve the boosters for launch despite the fact that the predicted launch temperature was outside of their operational specifications and any test conditions.

Engineers must learn from both the technical and organizational failures that led to the tragic Challenger accident. The Engineering Pathway digital library has information on several excellent case studies, lesson plans and other curricular materials that can be used in the classroom. The Texas A&M case, for example, leads to these discussions questions:

• “What could NASA management have done differently?
• What should Roger Boisjoly have done differently (if anything)? In answering this question, keep in mind that at his age, the prospect of finding a new job if he was fired was slim. He also had a family to support.
• What do you (the students) see as your future engineering professional responsibilities in relation to both being loyal to management and protecting the public welfare?”

For more information, see the Engineering Pathway’s resources on the Challenger accident or engineering ethics.

Today in History – January 26, 1926 – Scottish Engineer John Baird gives first public demonstration of television in London. According to BBC News, his first prototype in 1924 was crudely made of a washstand, a tea chest and a project lamp in a biscuit tin, scanning disks made from carboard and lenses, all held together with srcap wood, darning needles, strings and sealing wax. Nevertheless, he managed to transmit a flickering image for a few feet. On 26 January 1926, he gave the first world’s demonstration to fifty scientists in London. By 1927 he was transmitting an image of over 438 miles between London and Glasgow and started the Baird Television Development Company. Other firsts include: first transmission of a human face in 1925 (see right photo above), first transatlantic television transmission between London and New York in 1928 and first demonstration of color and stereoscopic television.

Baird’s system was amazing in that it was entirely mechanical, but it couldn’t compete against new electronic systems, such as those being developed by Marconi in the United States. Marconi’s approach was ultimately adopted for early television systems, but Baird’s contributions paved the way by introducing the concept and providing the first proof of concept. Prior to this BBC (British Broadcasting Corporation) was concentrating on radio production because they thought television would be a passing fad. In 1936 they adopted a television service using the electronic television technology developed by Marconi and thus Baird’s contributions are less well known.

Check out the Engineering Pathway’s educational resources on the color television. For more educational resources, see our electrical engineering education and computer engineering education community pages. The Engineering Pathway also hosts Engineering Education communities in all ABET-accredited disciplines.

Also on this date in 1905, Cullinan Diamond (“Star of Africa”), the largest diamond ever found, is unearthed. On January 26, 1697,  Isaac Newton solves Bernoulli’s brachistochrone problem, inventing the “calculus of variations”. And in 1992, Americans with Disabilities Act went into effect.

Today in History – January 24, 1984 – Apple Computer unveils the Macintosh personal computer. Apple introduced “the Mac” through its famous “1984″ television commercial that was played at the 1984 Super Bowl. The imagery pitted Apple’s new generation of the people’s personal computer against the Orwellian IBM. The Mac was an innovation breakthrough in computer design with the introduction of the mouse and a graphical user interface at a relatively low price.  It was first sold with only a 400kb floppy drive to load the operating system and files, with no hard drive. Less than 50,000 units were sold after its introduction because of the limited memory and radical features. Sales got a big boost when the LaserWriter printer was introduced along with third party publishing software. The early Mac users provided an enthusiastic customer base of early adopters who formed community groups, participated in early testing and developed third part software using Apple’s user-friendly developer’s kit. My husband and I each bought one of the first offerings and have upgraded to new Apple models ever since. The summer of 1984 I accepted a faculty position at the University of California at Berkeley and my husband became an Apple developer and created software for astronomy enthusiasts.

A decade earlier on April 1, 1976, the Apple Computer Company was formed and released the Apple I computer, the first computer with a single circuit board. There was no assembly line as each Apple I was hand-built by Steve Wozniak in Steve Jobs’ parents’ home and required further assembly by the purchaser, including providing AC input voltages, wiring an ASCII keyboard to a DIP connector and wiring the video output pins to a monitor or to an RF modulator if a TV was used. Steve Wozniak showed the first one to the Homebrew Computer Club to get sales going. He had to sell his Volkswagen bus to help keep the company afloat.

Steve Wozniak designed the Apple II personal computer that was released on April 16, 1977, featuring a central processing unit (CPU), keyboard, floppy disk drive, and a $1,300 price tag. The Apple II launched the personal computer revolution. He left Apple in 1981 and went back to the University of California at Berkeley and finished his degree in electrical engineering and computer science there. Since then, he has been involved in various business and philanthropic ventures, including improving computer capabilities in schools.

So how do you build the first personal computer? Wozniak says when he teaches Personal Computer 101 he asks students to go to the Apple I Owners Club, founded in 1977 by Joe Torzewski. The site contains over 120 pages detailing the Apple I computer. It shows you what it was like to actually buy and assemble one. If you’ve never seen an Apple I, check this site out and see how the personal computer revolution began. Want to know more, read Wozniak’s book: iWoz: Computer Geek to Cult Icon: How I Invented the Personal Computer, Co-founded Apple, and Had Fun Doing It.

Check out the Engineering Pathway’s educational resources on Apple computers and history of computing. For more educational resources, see our electrical engineering education, computer science education and computer engineering education community pages. The Engineering Pathway also hosts Engineering Education communities in all ABET-accredited disciplines.

Today in History – January 17, 1871 - U.S. patent issued for an “endless wire rope way” cable car (No.110,971). The inventor of the cable car was Andrew S. Hallidie (center image above) and contracted by the Clay Street Hill Railroad Company in San Francisco. Hallidie’s system used a continuous looped wire rope that was placed in a tube below the surface of the ground. A motor kept the rope in continuous motion (first image below) and the rope was grasped and released by a griping device on the passenger car and controlled by the “driver”. Bells were used to warn other cars and pedestrians that a cable car was on its way. A code was developed so that the bell could be used to communicate between cable car drivers as well.

Legend has it that Hallidie’s inspiration for the cable car came in 1869 after witnessing horses being whipped while they struggled on the wet cobblestones to pull a horsecar up Jackson Street. When a horse slipped, it was sometimes dragged to its death.

Hallidie’s design was described in the Scientific American Supplement, September 17, 1881 with the title: The Wire Rope Street Railways of San Francisco, California. Hallidie describes how his cable car system operates and the various San Francisco companies (at that time) that had successfully adapted the cable car for their street railway company.

Andrew Smith Hallidie tested the first cable car at 4 o’clock in the morning, August 2nd, 1873, on Clay Street, in San Francisco. For more information, see the San Francisco Cable Car Museum and find out more about how cable cars work, their history and where they operate today. Or check out the Engineering Pathway’s educational resources on cable cars and mass transportation systems.

Cable cars are a great example of the application of simple machines and mechanical advantage. For more information see the Engineering Pathway’s curricular resources and the Mechanical Engineering Education disciplinary community.

Today in History – January 13, 1942 – Henry Ford patents a plastic automobile.

The plastic car Ford patented used soy-based plastics and was 25% to 33% lighter than conventional cars of his day. Ford’s dream was to use agricultural-based plastics to provide another market for farmers to sell their crops.

Sustainability in design is beginning to make a comeback as manufacturers are using recycled products in car interiors. However in today’s oil-conscious world, car manufacturers are focusing most heavily on hybrid vehicles and fuel diversity. A variety of new cars are equipped with engines that are designed to run on both traditional gasoline and an ethanol blend. And although many more plastics and composites are being used in cars, they are not of the type that Ford envisioned. A recent article in Business Week (“Lighter Cars Can Help the U.S. Kick Oil”) points out that vehicle weight has only risen over recent decades. A significant decrease in weight, like the one that Ford initially achieved, could be just as beneficial to fuel economy.

For more information, see the Engineering Pathway’s related resources plastics and their applications. Or visit the Materials Engineering Education or the Mechanical Engineering Education community sites.

Today in History – January 7, 1913 – William Merriam Burton is awarded the patent for thermal cracking. Cracking is a process where organic molecules and broken down into simpler molecules by breaking carbon-carbon bonds. This process is used to breakdown crude oil into one of its many products. These methods were pioneered in by Benjamin Silliman Jr in 1855. But prior to 1913 one of the most popular ways of turning crude oil into useful products was distillation process which collected different products as they condensed in a distillation tower. While this process worked it produced very little gasoline. Burton new this process wasn’t enough and wanted to improve the process just in case Henry Ford was right about automobiles. After years of testing in the laboratory William Burton developed the process of thermal cracking. In this process elevated temperatures and pressures (over 800C and 700kPa respectively) are used. This in effect doubled the yield from a single barrel of crude oil. In 1913 Burton received US Patent No. 1,049,667 for thermal cracking.

For more information, see the Engineering Pathway’s resources on petroleum refining. For related educational resources, visit the Petroleum Engineering Education disciplinary community.

Today in History – January 5, 1892 – Construction began on the Golden Gate Bridge. After years of gathering support and funding for the bridge, Joseph Strauss oversaw its construction. The project was so massive that a Golden Gate District was formed to build the bridge. All in all the bridge ended up costing about 27 million dollars. One of the most innovative parts of the bridge’s construction was Strauss insistence on safety. Workers wore protective headgear, glare-free goggles, and even a special lotion that helped protect against the harsh winds. There was also a large net that was placed beneath the workers. When construction was completed in 1937 the net had saved nineteen lives. At the time of completion the bridge was the longest suspension bridge in the world. And today it is still as iconic as it was 101 years ago.

For more information, see the Engineering Pathway’s resources on bridges. For related educational resources, visit the Civil Engineering Education or Construction Engineering Education disciplinary communities.

Also today in 1892, the first photograph of the Aurora Borealis was taken.

Today in History – January 3, 1957 – The world’s first electric wristwatch is released. The Hamilton watch company began research on an electric watch in 1946. Ten years later they released their watch with great success. Prior to this watch most watches kept time using a balance wheel that was kept in motion using a spring. This spring had to be wound by the wearer everyday. The Hamilton watch, while using the same balance wheel, used electromagnets to keep it in motion. One of the biggest challenges was finding a battery that was powerful enough to power the watch for a year, but also be small enough to fit inside the watch case. The Hamilton watch case styles were also an important ingredient in the watches success. People loved the their asymmetric design. However, this type of watch never gained mass popularity as they were only marginally better than their mechanical brethren. And by 1969 production stopped when quartz technology was used in favor of its accuracy.

For more information, see the Engineering Pathway’s resources on watch technology and time measurement. For related educational resources, visit the Computer Engineering Education, or the Electrical Engineering Education disciplinary communities.

Today in History – January 1, 1853 – The world’s first practical steam-powered fire engine made its debut.

In the spring of 1852, Abel Shawk, Alexander Bonner Latta, and Miles Greenwood began construction on the first practical steam-powered fire engine. While other fire engines had existed, theirs was significantly faster, being able to pump water in a mere ten minutes. Once finished they presented their engine to Cincinnati Fire Department on January 1st, 1853 (their own city). This engine was nicked name ‘Uncle Joe Ross’ and with the success of this and other steam powered fire engines, the City of Cincinnati went on to create the first professional fire department in the United States.

For more information, see the Engineering Pathway’s resources on fire-engines, fire-fighting and steam. For related educational resources, visit the Mechanical Engineering Education disciplinary community.