Lifelike Dinosaur Emerges From The Plumbing Aisle

Despite the incredible advancements in special effects technology since the film’s release, the dinosaurs in 1993’s Jurassic Park still look just as terrifying today as they did nearly 30 years ago. This has largely been attributed to the fact that the filmmakers wisely decided to use physical models in many of the close-up shots, allowing them to capture the nuances of movement which really helps sell the idea you’re looking at living creatures.

[Esmée Kramer] puts that same principle to work in her incredible articulated dinosaur costume, and by the looks of it, Steven Spielberg could have saved some money if he had his special effects team get their supplies at the Home Depot. Built out of PVC pipes and sheets of foam, her skeletal raptor moves with an unnerving level of realism. In fact, we’re almost relieved to hear she doesn’t currently have plans on skinning the creature; some things are better left to the imagination.

In her write-up on LinkedIn (apparently that’s a thing), [Esmée] explains some of the construction tricks she used to help bring her dinosaur to life, such as heating the pipes and folding them to create rotatable joints. Everything is controlled by way of thin ropes, with all the articulation points of the head mirrored on the “steering wheel” in front of her.

Now to be fair, it takes more than a bundle of PVC pipes to create a convincing dinosaur. Obviously a large part of why this project works so well is the artistry that [Esmée] demonstrates at the controls of her creation. Judging by her performance in the video after the break, we’re going to assume she’s spent a not inconsiderable amount of time stomping around the neighborhood in this contraption to perfect her moves.

In the past we’ve seen the Raspberry Pi used to upgrade life-sized animatronic dinosaurs, but even with the added processing power, those dinos don’t hold a candle to the smooth and organic motion that [Esmée] has achieved here. Just goes to show that sometimes low-tech methods can outperform the latest technological wizardry.

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Making a Flying Wing With Expanding Foam

Many radio control aircraft modelers will be familiar with the process of cutting wings out of foam with the hot wire method. The tools are simple enough to build at home, and it’s an easy way of producing a lightweight set of wings without too much hassle. [IkyAlvin] walks a different path, however (YouTube link, embedded below).

Expanding foam is the key here – that wonderful sticky material in a can that never quite goes where you want it to. MDF and foam is used to create a mold to produce the wing forms. It’s then a simple matter of loading floor underlay into the mold to act as the outer skin, and then filling the mold with expanding foam and waiting for it to cure.

The final parts are assembled into a flying wing, and the first test flight is remarkably successful. Using foam overlay as a skin also has the added benefit of providing a sleek silver finish to the aircraft. It goes to show that there’s always room to explore alternative techniques outside of the mainstream. If you’d like to get more familiar with the classic hot wire technique, though, we can help there too. Video after the break.

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Whirling Sawblades Turn Foam Packaging Into Wall Insulation

If you’re like us, the expanded polystyrene (EPS) foam inserts that protect many packages these days are a source of mixed feeling. On the one hand, we’re glad that stuff arrives intact thanks to the molded foam inserts. But it seems so wasteful, especially when chucking it in the garbage can. If only it could be effectively recycled.

It turns out that it can be, if you equip yourself with this spinning “sawblades of doom” EPS recycler. It comes by way of [HowToLou], who was looking for a way to insulate a wall on the cheap. Almost all commercially available insulating materials – fiberglass batts, blown-in cellulose, expanding polyisocyanurate – are pretty pricey. Foam packing pieces are pretty easy to come by, though, and usually free for the taking. [Lou]’s method of turning them into insulation is a box containing four circular saw blades mounted to a piece of threaded rod and spun by a cordless drill. The blades are mounted askew on the rod for better reduction of the foam; [Lou] chose to use wire to hold the blades down, while we’d have printed up some slanted arbors and bolted the blades down more firmly. A chicken wire prefilter keeps the big chunks from clogging a blower made from an old bathroom exhaust fan, which does a great job of filling the wall cavities with pulverized EPS nuggets. The video below has all the details.

Honestly, the box is a little scary, and we have doubts that [Lou] will be able to get enough foam to finish the job, but it’s still a clever little hack. Grinding things up seems to be a theme for him; check out his leaf collector or his apple cider press.

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Simple Sensor Provides Detailed Motion Capture for VR Hands

Consider the complexity of the appendages sitting at the end of your arms. The human hands contain over a quarter of the entire complement of bones in the body, use dozens of muscles both in the hand itself and extending up the forearm, and are capable of almost infinite variance in the movements they can create. They are exquisite machines.

And yet when it comes to virtual reality, most simulations treat the hands like inert blobs. That may be partly due to their complexity; doing motion capture from so many joints can be computationally challenging. But this pressure-sensitive hand motion capture rig aims to change that. The product of an undergraduate project by [Leslie], [Hunter], and [Matthew], the idea was to provide an economical and effective way to capture gestures for virtual reality simulators, which generally focus on capturing large motions from the whole body.

The sensor consists of a sandwich of polyurethane foam with strain gauge sensors embedded within. The user slips his or her hand into the foam and rests the fingers on the sensors. A Teensy and twenty lines of code translate finger motions within the sandwich into five axes of joystick movement, which is then sent to Unreal Engine, where finger motions were translated to a 3D-model of a hand to play a VR game of “Rock, Paper, Scissors.”

[Leslie] and her colleagues have a way to go on this; testers complained that the flat hand posture was unnatural, and that the foam heated things up quickly. Maybe something more along the lines of these gesture-capturing gloves would work?

Build Your Own Anechoic Chamber

For professional-level sound recording, you’ll need professional-level equipment. Microphones and mixing gear are the obvious necessities, as well as a good computer with the right software on it. But once you have those things covered, you’ll also need a place to record. Without a good acoustic space, you’ll have all kinds of reflections and artefacts in your sound recordings, and if you can’t rent a studio you can always build your anechoic chamber.

While it is possible to carpet the walls of a room or randomly glue egg crate foam to your walls, [Tech Ingredients] tests some homemade panels of various shapes, sizes, and materials against commercially available solutions. To do this he uses a special enclosed speaker pointed at the material, and a microphone to measure the sound reflections. The tests show promising results for the homemade acoustic-absorbing panels, at a fraction of the cost of ready-made panels.

From there, we are shown how to make and assemble these panels in order to get the best performance from them. When dealing with acoustics, even the glue used to hold everything together can change the properties of the materials. We also see a few other cost saving methods in construction that can help when building the panels themselves as well. And, while this build focuses on acoustic anechoic chambers, don’t forget that there are anechoic chambers for electromagnetic radiation that use the same principles as well.

Thanks to [jafinch78] for the tip!

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3D Printed Upgrade for Cheap Foam Glider

We know you’ve seen them: the big foam gliders that are a summertime staple of seemingly every big box retailer and dollar store in the world. They may be made by different companies or have slight cosmetic differences, but they all adhere to the basic formula: a long plastic bag containing the single-piece fuselage and two removable wings and a tail. Rip open the bag, jam the wings into the fuselage, and go see if you can’t get that thing stuck on a roof someplace.

But after you toss it around a few times, things start to get a little stale. Those of us in the Hackaday Collective who still retain memories of our childhood may even recall attempting to augment the glider with some strategically attached bottle rockets. But [Timothy Wright] has done considerably better than that. With the addition of a 3D printed “backpack”, he managed to add not only a motor to one of these foam fliers but an RC receiver and servos to move the control surfaces. The end result is a cheap and surprisingly capable RC plane with relatively little work required.

[Timothy] certainly isn’t claiming to be the first person to slap a motor on a foam glider to wring a bit more fun out of it, but his approach is very slick and of course has the added bonus of being available for other grownup kids to try thanks to the Creative Commons license he released the designs under. He mentions that variations in the different gliders might cause some compatibility issues, but with the generous application of some zip ties and tape, it should be good to go.

This particular hunk of foam might not set any altitude or distance records, and it certainly won’t be carrying you aloft, but it’s a pretty approachable summer project if you’ve got some RC gear laying around.

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Zen and the Art of Foam Core

Some of our pastimes are so deeply meditative that we lose ourselves for hours. Our hands seem to perform every step, and sequence like a pianist might recite her favorite song. If [Eric Strebel]’s voice and videos are any indications, working with foam core can have that effect.

Foam core is a staple of art stores, hobby stores, and office supply stores. It comes in different colors, but the universal trait is a sheet of foam sandwiched between a couple of layers of paper. This composition makes a versatile material which [Eric] demonstrates well in his advanced tutorial making a compound surface and later on a speaker mockup.

After the break, you can catch a couple of beginner tutorials which explain the differences between a slapdash foam core model, and one which will draw appreciation. Proper tools and thoughtful planning might be the biggest takeaways from the first two videos unless you count the Zen narration. The advanced videos, linked above, show some ingenious ways to use foam core like offset scoring, adjustable super-structures, and paper transfers.

Each video is less than ten minutes long, so if you just started your coffee break, you can complete a video right now. Or look at another 2D material turned into amazingness with a papercraft strandbeest, then step up your game with another look at vinyl cutters.
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