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X-Rayted Files: A Century of X-Rays in the Automotive Industry, Part 1

If you have read any of my previous columns, you know that I’m passionate about X-rays and cars. And electronics, which started as a hobby when I was age 9, turned into a passion after I received an associate degree in electronics when I was 13. It went downhill from there, meaning I’ve been looking forward to writing about these passions, and I can’t believe it’s finally here! What makes this experience even better is the fact I also have a chance to talk about some of my idols, including Curie, Roentgen, Marconi, Galvin, and Ford.

Here’s how this column will go. I’ll start in 1895, jump to World War I, stop by the 1930s, and wrap up with how X-rays are used in the automotive industry today. It so happens that brevity is not one of my few qualities, so I had to split this column into two parts. There’s a lot to cover, so let’s get going!

It all started in 1895 when Wilhelm Roentgen discovered X-rays in Germany. It didn’t take long for him to realize the potential impact of his discovery to society. To guarantee the fast and widespread use of X-rays, Roentgen decided not to patent his invention. It turns out he was right. By early 1896, Dr. Edwin Frost was taking X-rays of a broken arm in Dartmouth, Massachusetts. That’s an incredible adoption speed for a technology considering the people who invented the internet were not even born yet! Even by modern standards, X-ray had a meteoric adoption rise.

Unfortunately, things are not all rosy and peaceful in Europe. In 1914, the continent was at war. Curie and Roentgen have several things in common. They are both Nobel prize winners. They were also humanitarians, despite being on different sides of the Great War. Instead of using her creative juices to build bombs, Curie decided to join the war effort to save lives. She knew of the benefits of X-rays in finding a bullet inside a soldier’s leg. As a result, she invented the first car-based X-ray machine or the first X-ray machine on wheels—however you choose to describe the beautiful vehicle in Figure 1.

Figure 1: One of Curie’s mobile units used by the French Army (Source: National Library of France, Prints and Photography Department ^[1])

The history of the automotive and X-ray industries would be henceforth intertwined. Not much later, Henry Ford took X-rays of Model A radiator fans that broke due to poor casting. Fast forward a few decades, and we are taking computed tomography scans of casting automotive parts to look for the same problems (Figure 2).

Figure 2: Computed tomography (CT) scans of castings for an automotive application.

The history of X-ray inspection and the automotive industry came together again once electronics were introduced to cars. Interestingly, the first piece of electronics boarded on a car was the radio, which was invented by Guglielmo Marconi—also in 1895—in Italy, not far from Roentgen. By the early 1920s, radio stations were multiplying, and radios were becoming a staple piece of furniture in homes across the world.

In the late 1920s, Henry Ford was looking for a way to differentiate his cars from the stiff competition from GM. In 1930, brothers Paul and Joe Galvin showed old Henry how to add a victrola (radio) to a car. Their MOTOrized victROLA (guess the name of Galvin’s company) cost $130 and was revolutionary. For reference, the Ford Model A was being sold for $540. Galvin’s radio needed an extra battery (and sometimes an extra generator) to be added to the car (Figure 3). Unfortunately, despite all of Galvin’s marketing and technological efforts, the adoption of their new technology was slow on the heels of the Great Depression. It would be a couple of decades before Ford and others started selling radios in their cars as a factory option.

Figure 3: A circa-1930 brochure advertises a Motorola car radio.

Galvin’s breakthrough led to the convergence of X-rays, automobiles, and electronics. Radios became a part of cars. Like it did with radios, the automotive industry started to embed more electronics to their products, especially after the invention of the transistor in 1947 and the transistor radio in 1954. The increasing adoption of onboard electronics over the past seven decades has brought an increasing set of headaches to carmakers.

Next Time

In Part 2 of this column, I will review the many ways X-ray inspection helps the automotive industry assess the quality of their products. From the inspection of quad-flat no-leads (QFN) to ball grid arrays (BGAs) all the way to the verification of solder fill on through-hole vias (THV), X-rays are used daily in the manufacturing of automotive electronics. These systems need to operate under the worst conditions of temperature and humidity cycling, exposure to acids, vibration, shock, and others. The same car is supposed to operate in the cold winters of Alaska and the hot summers of Arizona. We’ll see how X-rays help make it happen!

References

• Timothy J. Jorgensen, “How Marie Curie Brought X-Ray Machines To the Battlefield,” Smithsonian Magazine, October 11, 2017.
• APS News: A Publication of The American Physical Society, “This Month in Physics History: November 8, 1895: Roentgen's Discovery of X-Rays,” November 2001, Volume 10, Number 10, p. 2.
• Timothy J. Jorgensen, Strange Glow: The Story of Radiation, Princeton University Press, February 2016.
• Industry Today, “Road Tunes: How Car Audio Systems Have Evolved,” June 30, 2017.
• Bryan McLaughlin, “Who Invented Radio?”

Dr. Bill Cardoso is CEO of Creative Electron.