HC-SR04 Isn’t The Same As Parallax PING))) But It Can Pretend To Be!

“It’s only software!” A sentence that strikes terror in the heart of an embedded systems software developer. That sentence is often uttered when the software person finds a bug in the hardware and others assume it’s going to be easier for fix in software rather than spin a new hardware revision. No wonder software is always late.

[Clint Stevenson] is his own hardware and software guy, as are most of us. He wanted to use the less expensive HC-SR04 ultrasonic rangefinder in a prototype. Longer term he wanted to have the choice of either a Parallax PING or MaxBotix ultrasonic sensor for their better performance outdoors. His hardware hack of the SR04 made this a software problem which he also managed to solve!

[Clint] was working with the Arduino library, based on the Parallax PING, which uses a single pin for trigger and echo. The HC-SR04 uses separate pins. Originally he modified the Arduino library to accept the two pin approach. But with his long term goal in mind, he also modified the HC-SR04 sensor by removing the on-board pull-up resistor and adding a new one on the connector side to combine the signals. That gave him an SR04 that worked with the single-pin based library.

We’ve seen Parallax PING projects for sensing water depth and to generate music. These could be hacked to use the HC-SR04 using [Clint’s] techniques.

[Arduino and HC-SR04 photo from Blax Lab]

Golf Cart Delorean

Quick Marty! We Have To Go Back, With The Golf Cart!

Talk about an awesome project. [Lucas Evanochko] was commissioned to build this totally rad Delorean style golf Cart for Red Deer College’s 30th annual Golf Tournament.

According to him, it’s been about 600 hours in the making – and they only started building it in July. This past week was its big unveiling, and it has had an overwhelmingly positive response so far!

They started with one of the club’s golf carts and modified it heavily, relying on the automotive expertise of [David Keykants] and [John Perrin] to turn it into the aw-worthy time machine it is today.  It has a 7” tablet built right into the dash to play music and use the Fluxy88 Time Circuits app. A big array of arcade buttons hooked up to an Adafruit Audio FX board play various sound bites from the movie, including the theme music!

All the accessories are powered off of a separate 12V system from the main 48V drive line. Oh and the Flux Capacitor? It’s controlled by a Trinket Pro. Check it out after the break. We love the detail that went into this!

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cpu

Reach Out And Touch Your Computer

[Carter Yagemann] found himself in a bit of a pickle. He uses his computer mostly for gaming, but would like to access it remotely from time to time to do a littler server work on the side. The problem is gaming computers eat up a lot of electrons and he didn’t want to waste them by leaving it on all the time. The obvious solution was to use the Wake on Lan function. Unfortunately, his motherboard did not support this technology.

Like any good hacker would do, [Carter] used an IoT board to connect the power button of his PC to the internet. He achieved this goal with a Particle Core board. His motherboard was an ATX variety, so wiring up two of the IoT board’s I/O pins to the power on pins on the motherboard was a simple task accomplished with the help of an inline resistor.

This hack is so easy that it’s a great alternative to the blinky LED first program we all know so well. Want to get started in the hacking community? This is a great way to get going.

Omaha Mini Maker Faire: Recycle All The Things

A young maker named [Allie] drew a lot of attention at the 2nd annual Omaha Mini Maker Faire. Her booth was full of the various creations she has designed and built herself throughout the course of her short life. The biggest draw was her green design dollhouse, which focuses on environmentally friendly living. With the exception of the LEDs lighting the interior, some tape, and the requisite bit of hot glue, the entire structure and its contents were made from recycled materials.

green-dollhouse-thumbThe cardboard structure features a kitchen, living room, bedroom, bathroom, and attic. Every piece of furniture and all the decorations are made from salvaged materials and packaging. One side of the roof holds a Snap Circuits board with a solar panel that powers some blue LEDs on the bedroom wall. [Allie] poured water down the other side of the roof to demonstrate the rain water collection system. The house’s rain barrel was made from a grated parmesan cheese container, which is perfectly designed for the airline tubing running into it from the recycled plastic guttering.

owl-says-noOne of [Allie]’s other projects is a disagreeable owl fashioned from cardboard and a salvaged canister. Hidden away beneath the owl’s platform lies a simple gear system attached to a key on the front. Turning the key causes the owl’s head to swivel back and forth. We tried to make it spin all the way around, but the full range of motion is about 270 degrees. She also brought Mountain Dew, a hummingbird model made from a spark plug and other metal bits and bobs, including a pair of soda can wings.

mountain-dew-hummingbirdIn addition to her crafty skills, [Allie] is one well-spoken tween. She was more than happy to discuss her creations in detail to anyone who would listen, which included at least two local journalists and this impressed reporter. We learned through a bit of light research that a robot [Allie] built a few years ago inspired a British toy company to produce a new doll, the Robot Girl Lottie. She’s an inspiration to makers of all ages.

Open Source Hardware Certification Announced

Last weekend was the Open Hardware Summit in Philadelphia, and the attendees were nearly entirely people who build Open Source Hardware. The definition of Open Source Hardware has been around for a while, but without a certification process, the Open Hardware movement has lacked the social proof required of such a movement; there is no official process to go through that will certify hardware as open hardware, and there technically isn’t a logo you can slap on a silkscreen layer that says your project is open hardware.

Now, the time has come for an Open Hardware Certification. At OHSummit this weekend, the Open Source Hardware Association (OSHWA) announced the creation of a certification process for Open Source Hardware.

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Why Are You Still Making PCBs?

Few things have had the impact on electronics that printed circuit boards (PCBs) have had. Cheap consumer electronics would not be as cheap if someone still had to wire everything (although by now we’d be seeing wiring robots, I’m sure). Between removing the human from the wiring process and providing many excellent electrical properties (at least, on a well-designed board), it isn’t surprising that even the cheapest examples of electronics now use PCBs.

For many years, the hallmark of being a big-time electronic hacker was the ability to make your own PCBs. There have been many ways that people have tried to bring PCB manufacturing into the hacker’s garage: stick on decals, light-sensitive blank PCBs, and even using laser printer toner (that last one spurred me to write a book on PCB layout many years back). You also see a lot of people using 3D printers or CNC mills to create PCBs. Hardly a week goes by that someone doesn’t ask me how to make a PCB in a home or small business lab.

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3D Cable Robot Uses The Building As Its Exoskeleton.

There’s not much information about this commercial product, but it looks so interesting, we just had to share it. It doesn’t seem there is anything too magical happening here: some motors (presumably some type of servo or stepper with positioning feedback) some cables and pulleys, and an end effector of your choosing. Oh, and just some clever math to solve the inverse kinematics – not that inverse kinematics is all that easy! You can see the robot at work in the video after the break.

Most likely you’ve already seen the end results of such a three-dimensional cable driven system on your TV. If you’re a fan of most field sports, the SkyCam system is what’s used to deliver the stunning aerial shots that really put you into the game. We’ve covered this sort of mechanism before, but only in two dimensions. Usually we see the concept used as a white-board plotter like this extremely methodical Polargraph or one built with K’NEX.

We can’t help but wonder how this might be adapted into other situations?  Perhaps, you could use small light-weight cables (fishing line) and pulleys to make a living-room beer delivery system or TV remote retrieval claw?  Or could it become the mechanics of a really large format 3D printer? If any of you do rig up some sort of house-hold beverage fetching robot, be sure to let us know via the tipline.

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