A Fast And Easy-to-use Vision Sensor

At Hackaday we don’t often feature kickstarter campaigns, but this one is worth noticing in our opinion. It is called Pixy, a small camera board about half the size of a business card that can detect objects that you “train” it to detect.

Training is accomplished by holding the object in front of Pixy’s lens and pressing a button. Pixy then finds objects with similar color signatures using a dedicated dual-core processor that can process images at 50 frames per second. Pixy can report its findings, which include the sizes and locations of all detected objects, through one of several interfaces: UART serial, SPI, I2C, digital or analog I/O.

The platform is open hardware, its firmware is open source and GPL licensed, making the project very interesting. It is based on a 204MHz dual core ARM cortex M4 & M0, uses a 1280×800 image sensor and can stream the processed camera output to your computer. You can get one Pixy in the kickstarter campaign for $59, which is not that expensive for what it is.

Dual Extruders In The Space Of One Stepper Motor

The new hotness in 3D printers is – and has been for a while – dual extrusion. With two extruders and the requisite filament supply, it’s possible to print objects in two colors or two different materials. There’s a problem with this setup, though: each extruder requires a separate motor, greatly reducing the print area should you want to print in two or more colors. [Carl] and [Brian] think they have the solution to this with their dual extruder that is powered by one stepper motor.

As you can see from the pic above, the idea is relatively simple. Two strands of filament are fed past one gear attached to a stepper motor. Each strand is moved into the hot end through two idler gears and side of the extruder feeds into the hot end is determined by the rotation of the motor. It’s really one of those, “why didn’t I think of that” ideas.

[Carl] and [Brian] are also offering a quad extruder, a dual-sized extruder able to pump four different filaments onto a printer bed. With this, we expect some people to experiment with CMYK (or CMYW) prints, truly turning any 3D printer into a machine that prints full color parts.

Continue reading “Dual Extruders In The Space Of One Stepper Motor”

Six Years, A Giant Robot, And A Kickstarter

robot

Since 2007, [Jamie Mantzel] has been building a huge remote-controlled walking robot. If you’ve been following him on his YouTube channel and blog, you’ve seen the very beginnings of him building a lumber mill to create a workshop, making the legs for his robot, and improving his welding rig. This week, though, has been very special. [Jamie] has finally finished his giant robot project, bidding closed the fevered dream of a madman who awakes to a 10 foot robot in his yard.

The giant robot is constructed nearly entirely out of scrap aluminum. In the interest of simplicity, [Jamie] has come up with some interesting techniques to scale up conventional RC gear to power huge motors swinging giant legs: the steering motors are powered by manual switches, but these switches are activated by servos. A brilliantly simple solution to driving high-current loads if we do say so ourselves.

[Jamie]’s robot has garnered a lot of attention over the years, so much so that toy companies have licensed his designs for a line of battling combat spiderbots. [Jamie] believes his robots should be more educational, so he’s launched a Kickstarter for his own version as a kit. With this kit, getting the bug tank robot up and running isn’t simply a matter of pulling it out of the box and installing batteries; [Jamie]’s version is an actual kit with linkages that must be assembled. We know which version we’d want.

It’s an amazingly impressive project, and we’re glad to see such an awesome cat has finally realized his dream of a walking aluminum arachnid of death.

Centimeter-level Precision GPS For $900

[Colin] and [Fergus] have been working with GPS for years now, and like most builders of really cool things, they’re often limited by the precision of off-the-shelf GPS units. While a GPS receiver is usually good for meters of accuracy,  this just isn’t good enough for a lot of projects. What you need is centimeter-level accuracy, something the guys have managed to do with their Piksi GPS receiver.

Where most GPS receivers only look at the data coming from the GPS satellites orbiting overhead, the Piksi uses another technique, real-time kinematics (RTK), to determine the receiver’s location with exacting precision. The basic idea behind RTK is to look at the carrier frequency of the GPS signals at 1575.42 MHz. This frequency has a wavelength of 19 cm, compared to the alternating 1s and 0s of the that are transmitted at around 1 MHz, or about 300 meters between each bit. While centimeter-level precision isn’t possible with only one receiver, two of these Piksi boards – one base station and one on a vehicle, connected via radio link – can make for a very exacting high-accuracy GPS receiver.

Previously, commercial RTK GPS systems have cost thousands of dollars – making a quadcopter or other homebrew project that relies on this level of precision nonsensical. [Colin] and [Fergus] have built hardware that can bring the price of this setup to under $1000. As a bonus, the Piksi board can also receive from other constellations such as Galileo and GLONASS. A very impressive piece of hardware, and we can’t wait to see the applications.

HackRF, Or Playing From 30 MHz To 6 GHz

Up on Kickstarter, [Michael Ossmann] is launching the HackRF, an inordinately cheap, exceedingly capable software defined radio tool that’s small enough to lose in your laptop bag.

The HackRF was the subject of a lot of interest last time it was on Hackaday – the ability to receive up to 6GHz allows the HackRF to do a lot of very interesting things, including listening in on Bluetooth, WiFi, and 4G networks. Also, the ability to transmit on these frequencies means a lot of very interesting, and quite possibly slightly evil applications are open to anyone with a HackRF. Like the RTL-SDR dongles, the HackRF works with GNU Radio out of the box, meaning all those cool SDR hacks we’ve seen so far will work with this new, more powerful board.

Compared to the USB TV tuner cards that were so popular a year ago, the HackRF has 10 times the bandwidth, is able to receive up to 6GHz, and is also able to transmit. It’s only half-duplex, so to receive and transmit simultaneously you’ll need two HackRFs, or maybe wait for a hardware revision that will hopefully come sooner rather than later.

Below you can check out [Michael]’s presentation at Toorcon where the HackRF was unleashed to the world.

Continue reading “HackRF, Or Playing From 30 MHz To 6 GHz”

ARM Dev Board With USB Uploading

[George and Bogdan] wrote in to tell us about a cool Kickstarter they’ve been working on. It’s called the MatchboxARM, and like other tiny-yet-powerful ARM dev boards floating around, this one features a very fast and capable processor and more than enough pins for just about any project. One interesting feature of this board, however, makes it stand out from the pack: it has a USB mass storage-based bootloader, meaning uploading new code is as easy as a drag and drop.

This isn’t the first dev board we’ve seen to sport this feature: the Stellaris Launchpad has had this for a while and even the lowly ATtiny85, in the form of a Digispark has a mass storage-based bootloader. The MatchboxARM, though, brings this together with a very powerful ARM microcontroller with enough I/Os, ADCs, PWM pins, and I2C and SPI ports for the most complicated projects.

Send An Arduino To The Moon For $300

sat

We’ve seen Kickstarter campaigns to put a single satellite into space and one to launch your own personalized postage-stamp sized satellite into low Earth orbit. This time, though, you can break the bonds of Earth and send your own Arduino compatible satellite on a collision course with the moon. The project is called Pocket Spacecraft, and exactly as its name implies, it allows you to send a small, flat, 8 cm diameter spacecraft to the surface of the moon.

The pocket spacecraft are made of metallized kapton, a very thin membrane stretched inside a loop of wire. On board this paper-thin spacecraft are a pair of solar cells and a bare die MSP430 microcontroller connected to a suite of sensors. Before launch, you can program your tiny space probe with commands to relay data back to Earth, either useful scientific data or a simple tweet.

These pocket spacecraft will be launched from a cubesat – a highly successful line of amateur spacecraft that are usually launched by hitching a ride with larger commercial satellites. To get from low Earth orbit to the moon is much harder than just hitchhiking, so the cubesat mothership comes equipped with either a solar sail or its own engine that electrolysed water into hydrogen and oxygen, the perfect rocket fuel.

Pocket Spacecraft is an amazingly impressive feat; there are literally dozens of amateur-built spacecraft orbiting above our heads right now, but so far none have ventured more than a few hundred miles away from their home planet. Getting to the moon with an amateur spacecraft is an amazing accomplishment, and definitely worthy of the $300 price tag.