Hacklet 74 – Well Balanced Projects

September 11, 2015 by Adam Fabio 1 Comment

Balance: we humans take it for granted. Without the sense of balance provided by our inner ears, we would have a hard time standing or walking around. What’s easy for us can be very hard for machines though. Projects that balance things have long been a challenge for engineers, makers and hackers. And rightly so, as building a machine to keep an object in balance often requires some novel electronic and mechanical solutions. This week’s Hacklet is all about projects that keep an object – or themselves – in balance.

We start with [Manuel Kasten] and Balance Wheel. Inspired by a project at Chaos Communication Congress, [Manuel] created a hack that looks timeless. A stainless steel ball is balanced on top of a wooden wheel. The system detects the ball’s position using a solar cell. More light on the cell means the ball is slipping off the wheel. The system counteracts this by spinning the wheel to oppose the falling ball. In the old days this would have been an analog system. [Manuel] made things a bit more modern by using an ATmega644p processor. The video shows the wheel spinning a bit fast, as the system was tuned for a ping pong ball rather than a heavy steel roller.

Next up is [Jason Dorie] with Sideway. Sideway is a two-wheeled skateboard that self-balances. One of the best parts of this project is that most of the mechanical components are from electric scooters, which means they are easy to source. The frame is even easier: A solid piece of plywood supports the rider and all the electronics. Two scooter motors are driven by a Sabertooth 2x32A motor controller. A Parallax Propeller performs the balancing act, obtaining IMU data from an ITG3200 digital gyro and an ADXL345 accelerometer. Speed is controlled by leaning forward and back, like a Segway. Steering is controlled by a Wiimote nunchuck. Sideway is powered by 3 cell LiPo batteries. [Jason] says this ride gets a lot of attention every time he takes it out.

[Dominic Robillard] developed his Stair-climbing self-balancing robot as part of his masters degree at the University of Ottawa. We don’t know what grade his advisors gave him, but we give this project an A+. The robot is a 4WD off-road monster. Two heavy-duty drive motors give it tank style steering. The most impressive part of the robot are the two arms which allow it to roll its entire chassis up and over obstacles which would stop much larger robots. [Dominic’s] robot isn’t just statically balanced though – it can rear up and ride on two wheels Segway style. If it does tip over, the arms will lift it right back up!

Finally, we have [Paul Bristow] with Terabalance. [Paul] got his hands on an early copy of the TeraRanger One, a Time of Flight (ToF) sensor developed at CERN. He decided to test it out by using it to balance a ping pong ball on a wooden bar. The sensor had to be slowed down quite a bit in this application, data is only read about 1000 times a second and averaged. An Arduino reads the distance data from the sensor and uses that data to drive a hobby servo. No PID loops here, in fact, Terabalance is a great example of how a proportional only system will hunt forever. That said, it is good enough to keep the ball on the balance bar.

There are a plenty of balancing projects on Hackaday.io. If you want to see more, check out the new well balanced project list! Did I miss your project? Don’t be shy, just drop me a message on Hackaday.io. That’s it for this week’s Hacklet, As always, see you next week. Same hack time, same hack channel, bringing you the best of Hackaday.io!

Want A Low-cost ARM Platform? Grab A Prepaid Android Phone!

September 10, 2015 by Adam Fabio 113 Comments

What would you pay for a 1.2Ghz dual-core ARM computer with 1GB RAM, 4GB onboard flash, 800×600 display, and 5 megapixel camera? Did we mention it also has WiFi, Bluetooth, and is a low power design, including a lithium battery which will run it for hours? Does $15 sound low enough? That’s what you can pay these days for an Android cell phone. The relentless march of economies of scale has finally given us cheap phones with great specs. These are prepaid “burner” phones, sold by carriers as a loss leader. Costs are recouped in the cellular plan, but that only happens if the buyer activates said plan. Unlike regular cell phones, you aren’t bound by a contract to activate the phone. That means you get all those features for $15-$20, depending on where you buy it.

The specs I’m quoting come from the LG Optimus Exceed 2, which is currently available from Amazon in the USA for $20. The same package has been available for as little as $10 from retail stores in recent weeks. The Exceed 2 is just one of several low-cost Android prepaid phones on the market now, and undoubtedly the list will change. How to keep up with the current deals? We found an unlikely place. Perk farmers. Perk is one of those “We pay you to watch advertisements” companies. We’re sure some people actually watch the ads, but most set up “farms” of drone phones which churn through the videos. The drones earn the farmer points which can be converted to cash. How does this all help us? In order to handle streaming video, Perk farmers want the most powerful phones they can get for the lowest investment. Subreddits like /r/perktv have weekly “best deals” posts covering prepaid phones. There are also tutorials on rooting and debloating current popular phones like the Whirl 2 and the Exceed 2.

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Hacklet 73 – Parallax Propeller Projects

September 4, 2015 by Adam Fabio 17 Comments

In 2006, Parallax, Inc wasn’t new to the electronics business. They’d been around since 1987. Still, for a relatively small company, jumping into custom chips is a big leap. Parallax didn’t just jump into some cookie cutter ASIC, they made their own parallel multi-core microcontroller. Designed by [Chip Gracey], the Parallax Propeller has 8 cores, called cogs. Cogs are connected to I/O pins and other resources by a hub. The Propeller saw commercial success, and continues to have a loyal following. This week’s Hacklet is about some of the best Propeller projects on Hackaday.io!

We start with retrocomputing prop star [Jac Goudsmit] and L-Star: Minimal Propeller/6502 Computer. [Jac] loves the classic 6502 processor. Inspired by [Ben Heckendorn’s] recent Apple I build, [Jac] wanted to see if he could replicate an Apple I with minimal parts. He built upon the success of his Software-Defined 6502 Computer project and created L-Star. The whole thing fits on a Propeller proto board with room to spare. The project uses a 6502, with a Propeller handling just about everything else. The system takes input from a PS-2 keyboard, and outputs via composite video, just like the original Apple I. As you can see from the photo, it’s quite capable of displaying Woz in ASCII. [Jac] has expanded the L-Star to support the Ohio Scientific C1P and CompuKit UK101, both early 6502 based computers.

Next up is [Mike H] with B-BOT. B-BOT is a balancing robot. [Mike] used B-BOT to learn about designing with the Propeller and programming in SPIN, the Prop’s built-in interpreted language. While slower than assembler, SPIN was plenty fast enough to solve the classic inverted pendulum problem. B-BOT’s primary sensor is a Pololu AltIMU-10. This module contains a gyro, accelerometer, compass, and altimeter all on one tiny board. Locomotion comes in the form of two stepper motors. Command and control is via X-Bee radio modules. All the parts live on a custom PCB [Mike] milled using his CNC router.

[Antti.lukats] created Soft Propeller, his entry in the 2015 Hackaday Prize. Soft Propeller doesn’t use a hardware Propeller at all. The core of the system is a Xilinx Zynq-7 chip, which contains an FPGA and a Dual Core ARM A9+ processor. Back in 2014, Parallax released the Verilog HDL code for the Propeller core. [Antti] has taken this code and ported it over the Zynq-7. With 256Kb of RAM, 16 MB of Flash and an LED, the entire system fits in a DIP package smaller than a stick of gum.

Finally, we have [Christian] with Pipman GPS Watch. There’s just something about the Pip-boy from the Fallout video game series. This Personal Information Processor (PIP) has spawned hundreds of projects from cosplayers and electronics hobbyists alike. [Christian’s] version uses a 4D systems TFT LCD to display those awesome graphics. Input comes through a 5 way navigation switch. A GPS and compass module provide all the navigation data Pipman needs. At the center of it all is a Parallax Propeller programmed in SPIN. [Christian] has a working prototype on his bench. He’s now working on modeling a 3D printed case with Blender.

There are a ton of Propeller projects on Hackaday.io. If you want to see more, check out our Propeller Project list! Did I miss your project? Don’t be shy, just drop me a message on Hackaday.io. That’s it for this week’s Hacklet, As always, see you next week. Same hack time, same hack channel, bringing you the best of Hackaday.io!

Firmware Factory: Bit Fields Vs Shift And Mask

August 28, 2015 by Adam Fabio 47 Comments

Working with embedded systems usually involves writing code which will interface with hardware. This often means working on the register level. It doesn’t matter if we’re talking about a UART, an analog to digital converter, an LCD controller, or some other gizmo. Sooner or later, you’re going to have to break out the datasheets and figure out how to talk to an external device. To succeed at this you must become a master of bit manipulation.

Hardware designers don’t like wasting space, so modes, settings and other small pieces of information are often stored as packed bits. Our processors usually access things a byte (or a word) at a time, so what is the best way to handle this? Like so many other topics in software engineering, there are multiple ways to skin this cat. In C (and its derivatives) there are two major options: shift and mask, and bit fields.

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Hacklet 72 – Burning Man Projects

August 28, 2015 by Adam Fabio 16 Comments

Burning Man is almost here! In just a few days, artists, hackers, makers, and engineers will converge on the Black Rock Desert in northern Nevada. They’ll endure the heat, the dust, and possibly a few bugs to create one of the largest outdoor art festivals in the world. Every year, the playa is covered with art cars, giant rolling barges, and fire-breathing animals covered in RGB LEDs. With so many projects to work on, it’s no surprise that quite a few Hackaday.io members (and Hackaday staffers) are burners. This week’s Hacklet is about some of the best Burning Man projects on Hackaday.io!

We start with [David Nghiem] and “The Deep” – DC’s Sonic Jellyfish Art Cart. There’s just something calming about a watching a luminescent jellyfish floating serenely through the dark ocean. [David] and his team are recreating that effect in the desert with The Deep. They’re hanging a giant jellyfish in front of a golf cart. The medusa will be festooned with yards of silk and other types of fabric to create a flowing effect. Lighting will come from 8 RGB LED strips, controlled by 15 Teensy LCs. The Teensys will keep the lights flashing to the beat of the music. Burners can dance inside the sculpture, because this jellyfish thankfully has no sting.

Bicycles are the preferred mode of personal transportation at Burning Man. As you might imagine, it can be pretty hard to find your bike among all the other parked cycles. [Bob Baddeley] has made this a bit easier with Anglerfish for Bikes. Real anglerfish have an illicium, which is a stalk with a lighted tip that hangs just in front of their mouth. The bioluminescent light lures prey to the fish. [Bob] is using an RGB LED illuminated ball to lure him to his bike. This anglerfish started life as a blinky globe from Amazon. [Bob] removed the original electronics and replaced them with a Bluetooth radio on his own custom PCB. A simple press of a button gets the ball shimmering and blinking, leading [Bob] to his ride.

Next up is [Jeremy] with Interactive Disco Dance Floor. Inspired by Saturday Night Fever and the music video for Billy Jean, [Jeremy] is creating a dance floor that responds to those dancing on it. The floor is lit by 80 meters of 5050 RGB LEDs, controlled by ATmega168s. The ATmega168’s are connected to a capacitive sensor made up of a chicken wire grid. The system is sensitive enough to pick up feet even when wearing thick motorcycle boots. All the processors connect to a central computer via an RS-485 network. This allows the computer to take over and drive pre-programmed patterns to the floor. The PC side code is written in JavaScript, so it’s easy to modify.

Finally, we have Hackaday.io’s own [Jasmine] with Glow Jacket. Walking around at night in Black Rock City can be dangerous. People running from party to party, high cyclists flying across the playa, you never know who might run into you! Having something to make sure you’re visible is a great start of a project. Keeping warm through the cold nights in the desert would be an added bonus. [Jasmine] sewed 32 feet of electroluminescent (EL) wire onto the back of a black parka. The wire ran to two AA battery-powered inverters hidden in the jacket. The hardest part turned out to be sewing all that EL wire to a jacket. Once all the stitching was done though, her husband [Ben] glows like a beacon in the night.

Burners unite! [Jasmine] has set the Hacker Burners project page as a meeting place for all burners and fans of Burning Man. If you’re interested, join up! If you’d like to see more Burning Man projects, I’ve got you covered with our new Burning Man project list. If I missed your project, don’t hesitate to drop me a message on Hackaday.io. That’s it for this week’s Hacklet. As always, see you next week. Same hack time, same hack channel, bringing you the best of Hackaday.io!

Hollywood Finally Gets Hacking Right With Mr. Robot

August 24, 2015 by Adam Fabio 114 Comments

Author’s note: I’m keeping spoilers out of this article, but they will surely show up in the comments.

A few weeks ago I started hearing about a new show on the USA network, Mr. Robot. The synopsis for the show was “Mr. Robot is a psychological thriller that follows a young programmer who works as a cyber-security engineer by day and a vigilante hacker by night.” Yeah, that sounds like another Hollywood crapfest. Cue crazy GUIs and virtual reality flybys representing hacking scenes. After watching the pilot though, I realized I couldn’t have been more wrong. I was hooked for the entire 10 week first season.

Let’s start with the hacking, which is the whole reason this article is here on Hackaday. Show creator [Sam Esmail] isn’t a hacker himself, but he is tech savvy enough to see how poorly hacking has been portrayed on TV and in the movies. He knew he could do it better. The solution was good consultants, in the form of [Michael Bazzell] and others. The team helped shape the show into a rather realistic portrayal of hacking techniques. Elliot Alderson (Rami Malek), the main character, is the “vigilante” hacker described in the synopsis. Within the first 10 minutes of the pilot, he is turning a child pornographer in to the police. How does he catch the creeper? Tor exit node exploits, of course.

The onion routing protocol is not as anonymous as you think it is. Whoever’s in control of the exit nodes is also in control of the traffic, which makes me the one in control.

This is an accurate description of some of the exploits which have been demonstrated on the tor network. There aren’t any VR hacking scenes to be found either. In fact, several characters watch and make fun of the “flu shot” scene in Hackers. In this show, the command line isn’t hidden, it’s celebrated. We see every command the characters type, from netstat to CAN bus dumps. In one scene, Elliot even fires up a windows virtual machine so he can run DeepSound on his Kali Linux box.

The hacking isn’t all software either. Everyone’s favorite Linux single board computer is featured prominently in the first season. We can’t knock a show where a character looks at another and says “Ok, we all know what a Raspberry Pi is, what’s your point?”

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Hacklet 71 – Waterborne Projects

August 21, 2015 by Adam Fabio 2 Comments

Water: Life on earth wouldn’t exist without it. 71 percent of the Earth is covered by water. That only leaves 29 percent for us humans to live – and not all of that land is inhabitable. Water is so important that most human settlements start near water of some sort. Water to drink, or water to move goods. With all this water in oceans, lakes, and rivers, it is no surprise that hackers, makers, and engineers alike build some incredible projects that work on and under the water.

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