GPS Clock Hat

Hat-Mounted Clock Requires Mirror For Wearer To Tell Time

February 14, 2015 by 13 Comments

[gfish] was planning on attending Burning Man and wanted to make something unique (and useful) to wear. He decided on a hat/clock hybrid. Just slapping a clock on a hat would be too easy, though. [gfish] wanted his hat to change time zones both via manual switches or physical location.

On the front of the hat there are 2 hands, as most clocks have. Each one is attached to one of two concentric shafts that run to the back of the hat. Each hand is individually controlled by an RC vehicle servo. Those of you familiar with RC servos know that a servos’ max rotation is about 180 degrees and is certainly not enough for a full revolution required by the clock. To fix this, there is a 3:1 gear set that allows a 120 degree rotation of the servo to move the clock hand a full 360 degrees. With this method, each hand can’t move past 12 and instead has to quickly move counter-clockwise to get where it needs to be in order to again start its journey around the clock face.

Mounted inside the hat there is an Arduino that controls the clock, a GPS shield to determine location and an RTC to maintain accurate time. Mounted on the side of the hat is a control panel that contains an overall on/off switch as well as a rotary switch for selecting a specific timezone or for engaging GPS mode. The whole thing is powered by a 9 volt battery.

If you like unnecessarily complicated top hats, check out this WiFi enabled message displaying one.

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Camry Battery

Fixing A Toyota Camry Hybrid Battery For Under Ten Dollars

February 14, 2015 by 185 Comments

[scoodidabop] is the happy new owner of a pre-owned Toyota Camry hybrid. Well at least he was up until his dashboard lit up like a Christmas tree. He did some Google research to figure out what all of the warning lights meant, but all roads pointed to taking his car into the dealer. After some diagnostics, the Toyota dealer hit [scoodidabop] with some bad news. He needed a new battery for his car, and he was going to have to pay almost $4,500 for it. Unfortunately the car had passed the manufacturer’s mileage warranty, so he was going to have to pay for it out-of-pocket.

[scoodidabop] is an electrician, so he’s obviously no stranger to electrical circuits. He had previously read about faulty Prius batteries, and how a single cell could cause a problem with the whole battery. [scoodidabop] figured it was worth testing this theory on his own battery since replacing a single cell would be much less expensive than buying an entire battery.

He removed the battery from his car, taking extra care not to electrocute himself. The cells were connected together using copper strips, so these were first removed. Then [scoodidabop] tested each cell individually with a volt meter. Every cell read a voltage within the normal range. Next he hooked up each cell to a coil of copper magnet wire. This placed a temporary load on the cell and [scoodidabop] could check the voltage drop to ensure the cells were not bad. Still, every cell tested just fine. So what was the problem?

[scoodidabop] noticed that the copper strips connecting the cells together were very corroded. He thought that perhaps this could be causing the issue. Having nothing to lose, he soaked each and every strip in vinegar. He then wiped down each strip with some steel wool and placed them into a baking soda bath to neutralize the vinegar. After an hour of this, he reassembled the battery and re-installed it into his car.

It was the moment of truth. [scoodidabop] started up his car and waited for the barrage of warning lights. They never came. The car was running perfectly. It turned out that the corroded connectors were preventing the car from being able to draw enough current. Simply cleaning them off with under $10 worth of supplies fixed the whole problem. Hopefully others can learn from this and save some of their own hard-earned money.

Ball Balancing Robot Uses New TOF Sensor

February 14, 2015 by 24 Comments

By now, you’ve most likely have seen or even played with an ultrasonic distance sensor. They work by emitting a sound, and then listening for the “ping” to return. The sensor can then tell how far an object is away by calculating the time in between. With sound waves traveling at 343.2 meters per second (768 mph), it’s no small task to measure the short time it takes for the sound to be emitted, then hit something a few feet away, and return. Now, imagine trying to do that with light.

Light in comparison moves at a whopping 299,792,458 meters per second (or about 671 million miles per hour). You’re going to have to have a pretty fast finger on a stopwatch to measure the time it takes for light to bounce back from an object a few inches away.

[Paul Bristow] is doing just that with the use of a new Time of Flight (ToF) sensor called the TeraRanger One. Developed in cooperation with CERN, this sensor uses a very narrow beam of light (listed as +/- 2 degrees) to accurately measure the position of an object to a resolution of 5mm, with distances up to 14 meters away. It boasts an impressive update rate of >1000 samples a second, and is very micro-controller friendly with UART, I2C, SPI, and PWM output.

[Paul] and his fellow hackers at the Post Tenebras Lab Hackerspace in Geneva got their hands on this sensor, and in a short time had a ball balancing robot up and running. The crude program is not running a PID controller, so the results seen in the video after the break aren’t that impressive. Also, the sensor isn’t exactly cheap at about $180 USD. Despite that, it will be interesting to see what applications these sensors will be used for. If you have any ideas, leave them in the comments below.

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Reverse Engineering Apple’s Lightning Connector

February 14, 2015 by 95 Comments

Introduced with the iPhone 5 nearly two and a half years ago, Apple’s Lightning connector has stymied the incredible homebrew electronics scene that was previously accustomed to the larger, older, better documented, and more open 30-pin connector. Now, finally, the protocols inside the Apple Lightning connector have been broken. We’re still a ways off from a Lightning breakout board, but this is the first proof that a serial console can be obtained through a Lightning connector. That’s the first step to totally owning an iDevice, and this is how all those exploits will start.

[Ramtin Amin] began the teardown of the Lightning connector began as most reverse engineering tasks should – looking at the patents, finding a source for the connectors, and any other products that use similar hardware. [Ramtin] found a Lightning to Serial converter powered by an STM32 microcontroller. Disassembling the firmware and looking at the output on a logic analyzer, [Ramtin] figured out part of the protocol, most of the wiring, and after some research, schematics for how an until-now unidentified chip in Lightning-enabled iProducts was wired.

The chip in question is colloquially known as the Tristar, and more accurately as a CBTL1608A1. During the teardown craze of the iPhone 5 launch, this chip was frequently identified as a DisplayPort Multiplexer. It is a mux, but not for DisplayPort – it’s only to connect the accessory (Lightning) UART, debug UART, baseband, SoC, and JTAG. This is the key to the castle, and being able to get through this chip means we can now own our iDevices.

The chip is an incredibly small BGA affair that [Ramtin] desoldered, reflowed onto a breakout board, and connected to an STM32 Discovery board. Using the techniques he used with other Lightning-enabled hardware, [Ramtin] was able to connect his iPhone and ever so slightly peek his head into the inner workings of his device.

It’s not complete control of an iDevice yet, but this is how all those future exploits will start. [Ramtin] uploaded a short video as a proof of concept, you can check that out below.

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1 hour quadcopter build

1-Hour Quadcopter Build

February 14, 2015 by 9 Comments

[marhar] was pretty confident in his quadcopter building skills when he made a bet to build and fly a quadcopter in just one hour! This is a big task but he saved valuable time by using some unlikely parts that were hanging around his parts bin. And to make the task a little more difficult, this build wasn’t done in a nice shop, either. It was built outside on a patio floor with the only power tools available being a hand drill, miter saw and small drill press!

The frame is made from cheap, sturdy and available scrap wood. The center plates are 1/4″ plywood and the arms are 3/4″ square fir strips. Notice the landing gear, yes, those are mini wiffle balls zip-tied to the wooden arms. Although an unlikely candidate for landing gear, they are surprisingly effective.

The flight controller board is an Ardupilot. [marhar] did use a flight controller that he previously had in another quadcopter. He used it as-is, and it worked, but no programming or configuration time is included in the 1-hour limit. Even so, it doesn’t take away from the impressiveness of the build time.  The motors, ESC’s and battery are just standard types used for most multirotors.

[marhar] doesn’t say what he won for completing the ‘copter but we hope it was something good, he deserves it. If you’d like to make something similar, [marhar] gives very detailed instructions and provides templates for the wood parts on his Instructables page. Check out the time-lapse build video after the break…

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Bill’s Arduino

February 13, 2015 by 10 Comments

Pokemon is a great game by itself, but when you realize that not all of the ‘mon are available in one game, trading is required for completion, and some pokemon aren’t available without either hacking or going to a Toys ‘R Us in 1997, you start to see how insidious this game can be. Figuring he could finally complete the game with an Arduino, [Pepijn] decided to build a pokemon storage system.

This build was inspired by an earlier post that also spoofed trades. Instead of building this project around a high-power micro, [Pepijn] decided to use an Arduino. The protocol Game Boys use to communicate with each other is extremely well documented, although that’s only half the battle. Each game using the link cable used specialized data structures for transfer, and after grepping through a disassembled Pokemon ROM,  [Pepijn] figured out how everything worked.

The completed hardware keeps one Pokemon in the EEPROM of an Arduino. It’s not very fast if you want to catch all 151 Pokemon in the Gen 1 games, but any way you look at it, you’re going to be catching a lot of Magikarp anyway.

Wireless Water Level Sensor From PVC Pipe

February 13, 2015 by 25 Comments

[Bob] was having trouble keeping up with his water troughs. He had to constantly check them to make sure they weren’t empty, and he always found that the water level was lower than he thought. He decided it was time to build his own solution to this problem. What he ended up with was a water level sensor made from PVC pipe and a few other components.

The physical assembly is pretty simple. The whole structure is made from 1/2″ PVC pipe and fittings and is broken into four nearly identical sensor modules. The sensors have an electrode on either side. The electrodes are made from PVC end caps, sanded down flat at the tip. A hole is then drilled through the cap to accommodate a small machine screw. The screw threads are coated in joint compound before the screw is driven into the hole, creating its own threads. These caps are placed onto small sections of PVC pipe, which in turn connect to a four-way PVC cross connector. 

On the inside of the electrode cap, two washers are placed onto the screw. A stranded wire is placed between the washers and then clamped in place with a nut. All of the modules are connected together with a few inches of pipe. [Bob] measured this out so it would fit appropriately into his trough, but the measurements can easily be altered to fit just about any size container. The wires all route up through the pipe. The PVC pipe is cemented together to keep the water out. The joint compound prevents any leaks at the electrodes.

A piece of CAT 5 cable connects the electrodes to the electronics inside of the waterproof controller box. The electronics are simple. It’s just a simple piece of perfboard with an XBee and a few transistors. The XBee can detect the water level by testing for a closed circuit between the two electrodes of any sensor module. The water acts as a sort of switch that closes the circuit. When the water gets too low, the circuit opens and [Bob] knows that the water level has lowered. The XBee is connected to a directional 2.4GHz antenna to ensure the signal reaches the laptop several acres away. Continue reading “Wireless Water Level Sensor From PVC Pipe” →