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Spared No Expense: Cloning The Jurassic Park Explorer

23 May, by Tom Nardi[ —]

While you’d be hard pressed to find any serious figures on such things, we’d wager there’s never been a vehicle from a TV show or movie that has been duplicated by fans more than the Staff Jeeps from Jurassic Park. Which is no great surprise: not only do they look cool, but it’s a relatively easy build. A decent paint job and some stickers will turn a stock Wrangler into a “JP Jeep” that John Hammond himself would be proud of.

While no less iconic, there are far fewer DIY builds of the highly customized Ford Explorer “Tour Vehicles”. As a rather large stretch of the film takes place within them, the interiors were much more detailed and bears little resemblance to the stock Explorer. Building a truly screen accurate Jurassic Park Tour Vehicle was considered so difficult that nobody has pulled it off since the movie came out in 1993. That is until [Brock Afentul] of PropCulture decided to take on the challenge.

In an epic journey spanning five years, [Brock] has created what he believes is the most accurate Jurassic Park Tour Vehicle ever produced; and looking at the side by side shots he’s done comparing his Explorer to the ones from the movie, it’s hard to disagree. A massive amount of work went into the interior, leaving essentially nothing untouched. While previous builds have tried to modify the stock dashboard to look like the one from the movie, he built a completely new dash from MDF and foam and coated it in fiberglass. The center console featuring the large display was also faithfully reproduced from the movie, and runs screen accurate animations, maps, and tour information. The seats also had to be replaced, multiple times in fact, as he had a considerable amount of trouble getting somebody to upholster them to his standards.

But perhaps the most difficult component of all was the clear acrylic roof bubble. These were critical to filming the movie, as they not only let the viewer see down into the Tour Vehicles but also let the characters see out during the iconic tyrannosaurus attack. But because the roof bubble was created only for the movie and never existed as a real aftermarket product, it usually gets ignored in Tour Vehicle builds. It’s simply too difficult to produce for most people. The omission of the bubble was always considered a case of artistic license; in the same way nobody expects a replica DeLorean from Back to the Future to actually fly or travel through time.

But [Brock] wanted to take his Tour Vehicle all the way, so he partnered up with a local glass shop that let him rent time in their oven so he could heat up acrylic sheets. Once heated to the appropriate temperature, they could be removed and wrapped around a mold to make the bubble. The process took weeks to perfect, but in the end he and a few friends got the hang of it and were able to produce a gorgeous roof bubble that they fitted to the already very impressive Explorer.

While previous Jurassic Park Tour Vehicle replicas were unquestionably awesome, this build really does take it to the next level. Short of equipping the garage with a movie-accurate super computer, it’s hard to see how the bar can get any higher.

Restoring A 1930s Oscilloscope – Without Supplying Power

22 May, by Ben James[ —]

We’ve all done it: after happening across a vintage piece of equipment and bounding to the test bench, eager to see if it works, it gets plugged in, the power switch flipped, but… nothing. [Mr Carlson] explains why this is such a bad idea, and accompanies it with more key knowledge for a successful restoration – this time revitalising a tiny oscilloscope from the 1930s.

Resisting the temptation to immediately power on old equipment is often essential to any hope of seeing it work again. [Mr Carlson] explains why you should ensure any degraded components are fixed or replaced before flipping the switch, knowing that a shorted/leaking capacitor is more than likely to damage other components if power is applied.

The oscilloscope he is restoring is a beautiful find. Originally used by radio operators to monitor the audio they were transmitting, it features a one inch CRT and tube rectification, in a tight form factor.

[Mr Carlson] uses his capacitor leakage tester to determine if the main filter capacitor needs replacing – it does, no surprises there – as well as confirming the presence of capacitors potted into the power transformer itself. These have the potential to not only derail the restoration, but also cause a safety hazard through leakage to the chassis.

After replacing and rewiring everything that’s relevant, the scope is hooked up to an isolation transformer, and it works first time – showing the value of a full investigation before power-up. [Mr Carlson] quips, “It really doesn’t have a choice; when it’s on this bench, it’s going to work again”, a quote which will no doubt resonate with Hackaday readers.

[Mr Carlson] promises to integrate the scope into a new piece of test equipment in the near future, but in the meantime you can read about his soldering station VFD mod, or his walk-in AM radio transmitter.

Smiling Robot Moves Without Wires

22 May, by Brian McEvoy[ —]

What could be cuter than a little robot that scuttles around its playpen and smiles all day? For the 2018 Hackaday prize [bobricius] is sharing his 2D Actuator for Micro Magnetic Robot. The name is not so cute, but it boasts a bill of materials under ten USD, so it should be perfect for educational use, which is why it is being created.

The double-layer circuit board hides six poles. Three poles run vertically, and three of them run horizontally. Each pole is analogous to a winding in a stepper motor. As the poles turn on, the magnetic shuttle moves to the nearest active pole. When the perpendicular windings activate, it becomes possible to lock that shuttle in place. As the windings activate in sequence, it becomes possible to move left/right and forward/back. The second video demonstrates this perfectly.

[bobricius] found inspiration from a scarier source, but wants us to know this is his creation, not a patent infringement. We are not lawyers.

Here is a way to visualize just what is happening with those FETs. Watch as a power lead is brushed across the terminals in order. With this kind of basic kit, students could learn the value of motor acceleration, deceleration, or launching little magnets at their classmates.

Robert Hall and the Solid-State Laser

22 May, by Dan Maloney[ —]

The debt we all owe must be paid someday, and for inventor Robert N. Hall, that debt came due in 2016 at the ripe age of 96. Robert Hall’s passing went all but unnoticed by everyone but his family and a few close colleagues at General Electric’s Schenectady, New York research lab, where Hall spent his remarkable career.

That someone who lives for 96% of a century would outlive most of the people he had ever known is not surprising, but what’s more surprising is that more notice of his life and legacy wasn’t taken. Without his efforts, so many of the tools of modern life that we take for granted would not have come to pass, or would have been delayed. His main contribution started with a simple but seemingly outrageous idea — making a solid-state laser. But he ended up making so many more contributions that it’s worth a look at what he accomplished over his long career.

Merry Christmas

Robert N. Hall in his lab. Source: General Electric

Robert Hall, given the middle name Noel in honor of his arrival on Christmas Day in 1919, was an inquisitive lad from the start. It seemed that inventing ran in the family, with his uncle Sydney being an aircraft engine designer and self-described career inventor. At a young age, his uncle took him to a sort of industrial fair in his hometown of New Haven, Connecticut, where Robert got to see all sorts of demonstrations and displays of the latest electrical innovations. His uncle explained how everything worked, which inspired young Robert to read and study as much as he could.

By the time high school rolled around, he was experimenting in a lab he built in his bedroom. He also discovered astronomy and build his own telescopes from scratch. An obviously promising student, Robert was recruited by Caltech and won a scholarship just before the start of World War II. When his funds ran out, he worked at Lockheed Aircraft, gaining valuable experience in industry and making contacts that would serve him well later.

He finally finished his physics degree in 1942 and was recruited by General Electric for their Schenectady Research Lab. As a test engineer in an industrial R&D facility during a time of war and complete national mobilization, Hall had a chance to make an impact, which he took full advantage of. Working with a team focused on using magnetrons to jam German radar, Hall’s team designed and built the first continuous-wave (CW) magnetrons. These devices would be employed during the war, but would also go on to become the heart of every microwave oven in use today. It’s even said that the possibly apocryphal story of the Raytheon engineer who was inspired to build the first microwave oven by a melting chocolate bar had his pocket zapped by one of Hall’s CW magnetrons.

Hall was encouraged to leave GE and seek his Ph.D. in physics, again from Caltech. He returned to Schenectady in 1948, ready to head up a lab of his own in the relatively new field of semiconductors. In a perfect lesson in exquisite timing, Bell Labs announced the transistor shortly after he arrived, and the whole semiconductor field exploded. GE being GE, they were mainly interested in the uses of semiconductors in power electronics, so Hall worked on high-power transistors and germanium power rectifiers. He contributed greatly to the field with innovations in purifying germanium by fractional crystallization, achieving purities that no other group was capable of. He also worked on silicon transistors, inventing two ways to dope the silicon: alloying and impurity diffusion. Pretty much every transistor ever made can trace its lineage back to those two methods.

Challenge Accepted

Hall’s innovations made GE a leader in silicon transistors by the early 1960s, and secured Hall’s place as the leading expert on semiconductors. Word came to the physics world of the invention of the laser in May of 1960, and Hall and his team devoured all the information they could get on the new field that showed so much promise. But the early lasers were complicated and fussy devices, and the need for a simpler laser was clear.

Good-natured and well-liked by his peers, Hall was teased that since he had already invented so many things, he should take a stab at a solid-state laser. Even though he thought it would be impossible, he accepted the challenge and hit the books. He knew that gallium arsenide diodes could emit enormous amounts of infrared light, so he crunched the numbers and found that he might be able to make a laser from the stuff. He put together a small team and got to work, and within just a few days, they had built a working device from a crystal only 1/3 of a millimeter on a side. It needed liquid nitrogen cooling and only worked in pulse mode, but the world finally had a laser that didn’t need pumping by an outside source of energy. The solid-state laser had arrived.

US Patent 3,245,002, for a “Stimulated Emission Semiconductor”

The GE team wrote up their results quickly and submitted a paper to the Physical Review Letters. Sadly, some chicanery resulted when the paper was sent out for peer review. Two of the reviewers were from two different competing corporate labs working on solid-state lasers, and when they read of Hall’s success, they short-circuited the process and held a press conference to announce that they had “invented” the solid-state laser. Luckily, Hall’s patent was granted along with the others; in any event, his team was the first to publish, so there’s little doubt as to the fatherhood of the solid-state laser.

Hall continued working at GE until his retirement, racking up 43 patents and 81 publications. His other work impacted the fields of nuclear physics, where his high-purity semiconductors are used for sensitive gamma-ray detectors. And while GE never developed Hall’s laser into a commercial product — the work of building a continuous-wave room-temperature solid-state laser was left to others — every single point-of-sale barcode scanner, CD player, laser pointer, and perhaps most importantly, every fiber optic connection that would eventually stitch together the backbone of the Internet, all trace back to that tiny crystal on Robert Hall’s lab bench in 1962.

Hacking a Cheap Laser Rangefinder

22 May, by Tom Nardi[ —]

When a new piece of technology comes out, the price is generally so high that it keeps away everyone but the die hard early adopters. But with time the prices inch down enough that more people are willing to buy, which then drives the prices down even more, until eventually the economies of scale really kick in and the thing is so cheap that it’s almost an impulse buy. Linux SBCs, Blu-ray lasers, 3D printers; you name it and the hacker community has probably benefited from the fact that it’s not just the hacker community that’s interested anymore.

Which is exactly what’s started to happen with laser rangefinders. Once almost exclusively a military technology, you can now pick a basic “laser tape measure” for less than $40 USD from the normal overseas suppliers. Unfortunately, as [iliasam] found, they aren’t particularly well suited other tasks. For one there’s no official way of getting the data out of the thing, but the other problem is that the sample rate is less than one per second. Believing the hardware itself was promising enough, he set out to reverse engineer and replace the firmware running on one of these cheap laser rangefinders (Google Translate from Russian).

His blog post is an absolute wealth of information on how these devices operate, and a must read for anyone interested in reverse engineering. But the short version is that he figured out a way to reprogram the STM32F100C8T6 microcontroller used in the device, and develop his own firmware that addresses the usability concerns of this otherwise very promising gadget.

With some minor hoop jumping, the laser tape measure PCB can be hooked up to an ST-Link programmer, and the firmware provided by [iliasam] can be used to enable an easy to use serial interface. Perfect for pairing with an Arduino or Raspberry Pi to get fast and accurate range data without breaking the bank.

It probably won’t surprise you to see this isn’t the first time [iliasam] has gotten down and dirty with a laser rangefinder. This extremely impressive build from last year allowed for incredibly accurate 3D scans of his room, and before that he created his own rangefinder from scratch.

Hands-On: Flying Drones with Scratch

22 May, by Al Williams[ —]

I’ll admit it. I have a lot of drones. Sitting at my desk I can count no fewer than ten in various states of flight readiness. There are probably another half dozen in the garage. Some of them cost almost nothing. Some cost the better part of a thousand bucks. But I recently bought a drone for $100 that is both technically interesting and has great potential for motivating kids to learn about programming. The Tello is a small drone from a company you’ve never heard of (Ryze Tech), but it has DJI flight technology onboard and you can program it via an API. What’s more exciting for someone learning to program than using it to fly a quadcopter?

For $100, the Tello drone is a great little flyer. I’d go as far as saying it is the best $100 drone I’ve ever seen. Normally I don’t suggest getting a drone with no GPS since the price on those has come down. But the Tello optical sensor does a great job of keeping the craft stable as long as there is enough light for it to see. In addition, the optical sensor works indoors unlike GPS.

But if that was all there was to it, it probably wouldn’t warrant a Hackaday post. What piqued my interest was that you can program the thing using a PC. In particular, they use Scratch — the language built at MIT for young students. However, the API is usable from other languages with some work.

Information about the programming environment is rather sparse, so I dug in to find out how it all worked.

Programming Setup

As with a lot of hardware programming tasks, setting up the toolchain is the most frustrating part. You need to use the offline version of Scratch which requires Adobe Air. I had trouble getting this to work on a Linux system so I  finally gave up and installed it on a Windows laptop.

Scratch, though, is just part of it. You also need to install nodejs and a few files from Ryze Tech (PDF). The Ryze files are installed via a hidden menu command accessed by holding shift while clicking “File”. You are then greeted with the “Import Experimental HTTP Extension,” option. Once this is complete you’ll wind up with some blocks in the “More Blocks” category shown here. Tello acts as a WiFi access point and control is established when you connect to it with your computer and run the nodejs server from the command prompt.

There is API documentation (PDF) available if you’d like to look under the hood. From reading the API documentation, I learned the move units are in centimeters and some have minimums as well as maximums. The blocks will let you set any value you want, though. It just won’t have the desired effect.

A Simple Program

I put together a quick little Scratch program. It just runs a simple pattern and adds some sound effects (from the PC, not the drone). I immediately discovered a gotcha.

The blocks simply issue commands, but there is no feedback. For example, if you send a fly forward command followed by a rotate command, the rotate command will fall on deaf ears. You must give the drone time to execute each command. From Scratch, I didn’t see a way to wait for the response, so you simply have to guess how long something is going to take.

You can probably puzzle most of this out. The top block tells the program to start when you press the Go flag (part of the Scratch environment). The purple launch and landing sounds are just recordings located on the computer. The gold boxes are all for control.

Talking through this program: the drone takes off, moves forward in 3 spurts, rotates 180 degrees, then moves forward in 4 spurts. Then it backs up the last spurt and lands.

Fly blocks have a minimum distance of 20 cm. In my program, I set a “fly up” block to 10 to test this. The drone won’t respond to this block unless you change that to at least 20. If you find your commands are not being executed, it may be worth reading the API documentation I mentioned before to see if you are within the minimum and maximum ranges for each block.

How’s it Work?

It works. This drone uses an optical sensor for position awareness. This is not GPS, it’s more like how an optical mouse sensor works. You can see the optical sensors on the underside of the Tello as the drone files over the New York skyline (sort of) in the picture to the left.

If you don’t have a lot of light for the optical sensors, all bets are off. But if you do, it works pretty well. The rotation seems spot on. There was a little drifting around, so the takeoff and landing were not always exactly in the same spot, but it was close.

So it did work. I’m not sure it would be ideal for a beginner since the set up is frustrating and the lack of feedback can be confusing. For exciting kids about programming, you’d be better served with Lego Mindstorms or some similar offering.

For those that do have experience with coding, you may want to investigate the non-Scratch bindings. There are other bindings to the API, like programming Tello using Go which we covered last month. And there’s also the secret API the official applications use, which has been decoded by a community effort.

For $100, even if you don’t care about programming them these drones are great little fliers. Add a $30 Bluetooth controller and they get better (the Bluetooth connects to your phone, not the drone). When they start getting discounted for half the price they’ll be no-brainers.

Raspberry Pi Keeps Cool

22 May, by Al Williams[ —]

In general, heat is the enemy of electronics. [Christopher Barnatt] is serious about defeating that enemy and did some experiments with different cooling solutions for the Raspberry Pi 3. You can see the results in the video below.

A simple test script generated seven temperature readings for each configuration. [Barnatt] used a bare Pi, a cheap stick-on heatsink, and then two different fans over the heatsink. He also rigged up a large heatsink using a copper spacer and combined it with the larger of the two fans.

We aren’t sure if we would have used his methodology for these tests. The script executes quickly and it wasn’t clear that the temperature rise was leveling off. We weren’t sure just how much this was loading the CPU either. However, the results matched up with what you’d expect, so the script and data generation methods were probably fine.

The really interesting part to this wasn’t so much the results. We expected a bigger fan to do better and bigger fan and heat sink to do best of all. However, it was interesting watching the way the different cooling systems were mounted on the Pi and powered. The final solution — which was overkill anyway — was not mounted in a way that would lend itself to deployment. But the rest of the fan and heatsink combinations could easily be adapted for real projects.

If you really want to get serious, you can always plunge the Pi in oil. Or mount a thermoelectric heat pump and dump the excess heat into a bucket of water. But for most of us, just about any of the fan solutions here will be more than enough.

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