Friday, February 28, 2014 - 19:00Computers Playing Flappy Bird. Skynet Imminent. Humans Flapping Arms.
After viral popularity, developer rage quits, and crazy eBay auctions, the world at large is just about done with Flappy Bird. Here at Hackaday, we can’t let it go without showcasing two more hacks. The first is the one that we’ve all been waiting for: a robot that will play the damn game for us. Your eyes don’t deceive you in that title image. The Flappy Bird bot is up to 147 points and going strong. [Shi Xuekun] and [Liu Yang], two hackers from China, have taken full responsibility for this hack. They used OpenCV with a webcam on Ubuntu to determine the position of both the bird and the pipes. Once positions are known, the computer calculates the next move. When it’s time to flap, a signal is sent to an Arduino Mega 2560. The genius of this hack is the actuator. Most servos or motors would have been too slow for this application. [Shi] and [Liu] used the Arduino and a motor driver to activate a hard drive voice coil. The voice coil was fast enough to touch the screen at exactly the right time, but not so powerful as to smash their tablet.
If you would like to make flapping a bit more of a physical affair, [Jérémie] created Flappy Bird with Kinect. He wrote a quick Processing sketch which uses the Microsoft Kinect to look for humans flapping their arms. If flapping is detected, a command is sent to an Android tablet. [Jérémie] initially wanted to use Android Debug Bridge (ADB) to send the touch commands, but found it was too laggy for this sort of hardcore gaming. The workaround is to use a serial connected Arduino as a mouse. The Processing sketch sends a ‘#’ to the Arduino via serial. The Arduino then sends a mouse click to the computer, which is running hidclient. Hidclient finally sends Bluetooth mouse clicks to the tablet. Admittedly, this is a bit of a Rube Goldberg approach, but it does add an Arduino to a Flappy Bird hack, which we think is a perfect pairing.
Friday, February 28, 2014 - 16:00Can’t Stand Your Noisy Fan? Here’s a Plan, Man
[Brian] adores his GW Instek GPC-1850D power supply, but it’s annoyingly loud and disruptive to his audio projects. The thing works great, so he decided to regulate the fan’s speed based on usage level to save his sanity.
Once [Brian] got under the hood, he found that it actually has four separate heatsinks: one for the bridge rectifiers and one for each power transistor on the three output channels. The heatsinks are electrically and thermally isolated from each other and change temperature based on the channel being used.
[Brian] and his associates had several Microchip MCP9803 temperature sensors kicking around the lab from previous projects, so they put one on each heatsink. The great thing about these is their address selection pins which let all four of them sit together on the I²C bus to Arduinoville. Each sensor is insulated and clamped to its heatsink with a piece of meccano and a dab of thermal paste.
[Brian] used an Arduino Mini and built the circuit on stripboard. The fan runs at 24V, so he’s sharing that with the Arduino through a 7805. He controls the speed of the fan with PWM from the Arduino fed through a MOSFET. The Arduino reads from each sensor and determines which one is hottest. [Brian] wanted the fan to run at all times, so he set a base speed of 20%. When the heatsinks reach 30°C/86°F, the fan speed is increased to 40%. After that, the speed increases at 5°C/9°F intervals until it reaches max speed at 65°C/149°F.
Filed under: Arduino Hacks
Friday, February 28, 2014 - 13:00Homebrew Phase Laser Rangefinder
Just when you thought ARM micros couldn’t get any cooler, another project comes along to blow you away. [Ilia] created a phase laser rangefinder (.ru, Google translatitron) using nothing but a laser diode, a pair of magnifying glasses, a few components and an STM32F4 Discovery dev board.
The theory behind this build is using a laser’s phase to determine how far away an object is. By modulating the laser diode’s output at a few hundred Mhz, the reflection from the laser can be compared, giving a fairly reasonable estimate of how far away the target is. This method has a few drawbacks; once the reflection is more than 360 degrees out of phase, the distance ‘loops around’ to being right in front of the detector.
The laser diode used does not have any modulation, of course, but by using an STM32F4 ARM chip, [Ilia]was able to modulate the amplitude of the laser with the help of a driver board hacked out of a 74HC04 chip and a few resistors. Not ideal, but it works.
The receiver for the unit uses a photodiode feeding into the same microcontroller. With an impressive amount of DMA and PLL wizardry (the STM32F4 is really cool, you know), the phase of both the transmission and reflection can be compared, giving a distance measurement.
It’s all an impressive amount of work with a hacked together set of optics, a cheap dev board, and a few components just lying around. For any sort of application in a robot or sensor suite this project would fall apart. As a demonstration of the theory of phase laser rangefinding, though, its top notch.
You can check out a video of [Ilia]‘s rangefinder below. Be sure to full screen it and check out the distance measurement on the LCD. It’s pretty impressive.
Thanks [Володимир] for the link.
Filed under: laser hacks
Friday, February 28, 2014 - 10:01Wireless Charging… Have a Heart
[Gal Naim] recently finished off an awesome Valentine’s day present for special someone. It’s a wireless charging heart for your phone!
He already had the Qi wireless charger but wasn’t much of a fan as it “looks so boring”. So he took it apart to salvage the charging circuit for his new project. As luck would have it, the Qi is very simple on the inside — all he had to do was lengthen the power wires to the coil. He then designed his heart in SolidWorks — Don’t forget to check out our 3D Printering tutorials on this — and printed it out in a nice candy apple red. To maximize the charging current he’s left the inductive loop on the outside so it can be as close to the phone as possible — he spray painted it red and it actually looks pretty cool!
The next step was adding the wireless charging capability to the phone, we’ve covered how to add this to any phone before, but for [Gal] it was as simple as cutting down the Qi Receiver card to fit in the phone.
If you want a bit more of a challenge though you can always make your own inductive charging loop!
Filed under: wireless hacks
Friday, February 28, 2014 - 07:00Ridiculously Accurate Mission Control Panel
We are absolutely blown away by the level of detail that went into this amazing mission control panel that [Jeff Highsmith] made for his son.
His kid just started school and needed a desk to do homework on. They had recently visited the Kennedy Space Center, and his son found a new interest in all things space – So [Jeff] took the opportunity to make the desk into this mind-boggling control panel.
We saw a similar project recently, but this one seems to take it to the next level. The desk itself is hand-made from MDF sheet and with oak boards making up the structural members. He’s cut out over a dozen individual control panels, added switches, LEDs and potentiometers, and printed the labels on transparencies which give the whole thing a very professional and finished look. An iPad sits in the middle which plays a curated collection of space videos.
As far as we can tell, all the buttons actually do something. He’s using an Arduino with four I/O expanders (MCP23017) to take care of all the inputs and outputs, and a Raspberry Pi to add sound effects to the simulation.
Now all he needs is a spaceship to monitor — which apparently is in the works as well!
Friday, February 28, 2014 - 04:00Gamebuino: A Handheld Arduino Gaming Console Ready for Prime Time
[Rodot] wrote in to tell us about the Gamebuino, a very nicely designed and easily reproducible version of his handheld Arduino gaming console. We originally featured [Rodot's] Arduino based gaming console over a year ago.
With the Gamebuino, you too can build your own games and gaming hardware around the Arduino. While there is a lot of information currently missing from the site’s Wiki, such as the layout and game code, [Rodot] plans on making everything open source. The console includes a rechargeable lithium battery, a micro SD card, and I2C expansion connectors. This is one project to keep an eye (and two hands) on, especially since a full game library is going to be provided, letting you easily create your own games. See what the console can do in the demo video after the break.
It would be amazing so see some old Game Boy games ported to run on the Arduino, or maybe one of our readers can make an Game Boy emulator for the Arduino!
Filed under: Arduino Hacks
Thursday, February 27, 2014 - 23:00Sparkfun’s AVC 2014: Robots, Copters, and Red Balloons of Death, Oh My!
Registration is open for Sparkfun’s 2014 Autonomous Vehicle Competition (AVC)! Every year the fine folks at Sparkfun invite people to bring their robots, rovers, and drones to Colorado to see who is the king of the hill – or reservoir as the case may be. We see plenty of robots here at Hackaday, but precious few of them are autonomous. To us that means capable of completing complex tasks without human intervention. Sparkfun has spent the last five years working toward changing that. Each year the robots get more complex and complete increasingly difficult tasks.
The competition is essentially a race through the Boulder reservoir. Time is key, though there are multiple ways to gain bonus points. For aerial vehicles there are two classes: fixed and rotary wing. Planes fall under the fixed wing category. Helicopters, gyrocopters, tricopters, quadcopters, and beyond fall into rotary wing. We’re holding out hope that e-volo shows up with their Octadecacopter. Ground vehicles have a few more class options. Micro/PBR class is for robots with a build cost less than $350 total, or small enough to fit into box that’s 10″x6″x4″. The doping class is unlimited. Sparkfun even mentions costs over $1kUSD+, and weights over 25LBS. Non-Traditional Locomotion class is for walkers, WildCats and the like. Peloton is Sparkfun’s class for robots that don’t fit into the other classes.
Sparkfun is also making a few changes to the course this year. A white chalk line will be drawn through the course, so robots don’t have to rely on GPS alone for navigation. We’re hoping to see at least a few vision systems using that chalk line. Aerial robots will have to contend with three “Red Balloons of Death”. Robots can navigate around the balloons without penalty. The balloons can be bumped or even popped for bonus points, but the robot must do this with its own body. Projectile weapons are not allowed. To say we’re excited about the AVC would be an understatement. As much as we enjoy watching the big players at competitions like the DARPA Robotics Challenge, we love seeing individuals and small teams of hobbyists compete every year at the AVC. Click on past the break for Sparkfun’s AVC 2013 wrap up video.
Filed under: robots hacks
Thursday, February 27, 2014 - 22:00Persistence of Vision would make a Great HUD
[Eduardo Zola] has just put the finishing touches on this awesome real-time persistence of vision display which displays text as you type!
It looks like the display is mounted on a small DC fan, which [Eduardo] powers using a bench top power supply. This allows him to fine tune the speed manually, without adjusting the the actual POV controller. The display receives the characters from the keyboard via a small USB RF receiver, and it has got a pretty snappy response time.
There isn’t too much more info on the project, but it certainly gives us an idea — could persistence of vision be used to create a kind of heads up display in a vehicle? What do you think?
Filed under: led hacks
Thursday, February 27, 2014 - 19:01Fail of the Week: Reset Issues with 595 and HD44780
We really like to see hardware hackers stepping out of the safe and polished boundaries of available Arduino libraries. One example of this is a project which [Matteo] thought worked: using a shift register to drive a character LCD. This can be a desirable way to do things, because it takes the GPIO usage down from six to just three connections. If you don’t remember seeing that one earlier this month take another look. The gist of it is that [Matteo] hacked one function in the LiquidCrystal library to make it happen.
What makes this a truly great fail is that the problem was not immediately apparent, and is difficult to reliably reproduce. The LCD is unstable depending on how the Arduino board is reset. When connecting the Arduino to a computer the screen doesn’t work until you press the reset button. But press the reset button repeatedly and you get a non-functional screen plus the gibberish seen above.
There’s not much to go on here, but we think it’ll be a lot of fun to state your theory on the malfunction and suggesting for testing/fixing the issue. This could be a lot of things, the controller on the display getting mixed-up, the 595 missing an edge (or something along those lines). Do you fix this with hardware (ie: capacitor to avoid voltage dip), a software issue (need a longer delay after startup), or a combination of the two?
Fail of the Week is a Hackaday column which runs every Wednesday. Help keep the fun rolling by writing about your past failures and sending us a link to the story – or sending in links to fail write ups you find in your Internet travels.
Thursday, February 27, 2014 - 16:00Mini Go Kart Built In A Day
The crew at the MIT student-run shop MITERS love their go karts, and when sitting around a pile of parts in the middle of the night on Saturday, there was only one thing to do: build a mini electric go kart in a day.
The parts for this were all taken from the jumble of parts lying around the shop: a few scooter wheels, some aluminum tubing, a 1×4″ piece of extrusion, a huge motor, and a ton of A123 cells were enough to ge tthe project started. They began by bolting the back wheel and motor to the aluminum extrusion and machining a simple steering mechanism.
The real fun began when they realized they could fill the aluminum extrusion with batteries, creating a 6S5P pack with the balance connectors and – after a few tries – the proper insulation. Combine all the parts with a Kelly motor controller and an old Brooks saddle, and the MITERS have a fairly light mini go kart that can cruise around the halls at about 15mph. Not much, but it was built in a single sleep-deprived night.
Video of the kart in action below.
Filed under: transportation hacks
Thursday, February 27, 2014 - 13:00Taste-O-Vision Is Now A Thing
Not satisfied with late 1950s concepts of Smell-O-Vision [Nimesha] has created something extraordinary: A digital taste sensor, capable of representing taste with a little bit of heat, electricity, and an Arduino
The device purportedly works by via thermal and electrical stimulation of the tongue using silver electrodes. According to this video, different tastes are created with different currents and temperatures. For example, a sour taste is produced on the electrodes by varying the current from 60uA to 180uA and increasing the temperature up to 30 degrees C. Mint is produced by simply decreasing the temperature from 22C to 19C.
The control electronics include an Arduino, a motor controller, and a heat sink attached to one of the silver electrodes. Communication is done through USB, and of course there’s a mobile app for it, more specifically a protocol called Taste Over IP. This allows anyone to send a taste to anyone with one of these devices.
Videos below, and before you laugh, we’d really like to try one of these out.
Thanks [Jess] for the tip.
Thursday, February 27, 2014 - 10:00RFID Keepsake Box is Sweet and Secure
[Mike Buss] wanted to make his girlfriend something unique for her upcoming birthday — she had mentioned she wanted something to keep small mementos in, but [Mike] decided to step it up a notch on the awesomeness scale.
You see, a few years ago [Mike] read about the Reverse Geocache Puzzle by [Mikal Hart], which is an awesome box that gives you feedback as to how far away you are from the “secret” location that the box will open at — To raise the stakes however, if you ask for the distance more than 20 times it locks itself forever! Now, unfortunately, a memento box wouldn’t be very useful if you had to go to a secret place every time you wanted to open it… so [Mike] decided to secure it another way, using RFID!
It makes use of an Arduino, a Parallax RFID Reader, a micro servo, a button, an RGB LED, and a cleverly designed latch made of a metal eye hook and small copper rod. Since the box is battery powered, [Mike] has added an extremely clever fail safe mechanism. The 9V battery inside includes two extra contacts to the outside of the box via small screws. Completely inconspicuous, but if the battery is dead, simply hold a new 9V to the screws with the RFID card in place, and bam, the box opens!
We’re pretty sure she’s going to like it — check it out after the break!
Filed under: Arduino Hacks
Thursday, February 27, 2014 - 07:00Giant Tetris Adds some Retro to your Room
The build makes use of a 10 x 20 grid of RGB LEDs controlled by the myRIO. It’s played by using a web interface on any device, as long as you have WebSockets support. [Sam] had originally built it using an Arduino at the heart, but wanted a stand-alone device to do everything — no extra computer or Raspberry Pi for the web interface. That’s when he discovered the myRIO — it’s a pretty cool piece of hardware that we haven’t seen too much of yet, other than the recent Picasso with a Paintball gun project…
Don’t forget to watch the following video to see the game in action!
Filed under: Microcontrollers
Thursday, February 27, 2014 - 04:00Twitch Plays Pokémon: Better than Prime Time TV
Gameplay is simple – users type their command (Up, Down, A, B) into their IRC or web client. In the original configuration, commands were processed in the order they arrived at the game. The system worked until the whole thing went viral. With thousands of people entering commands at any given time, poor “RED” would often be found spinning in place, or doing other odd things. The effect is so compelling that even [Randal Munroe] has written an XKCD entry about it. To help the players get through some of the tricky parts of the game, [TPP's creator] added a game mode selection. Users can play in “Democracy” where the system takes votes for several seconds, then issues the highest voted command. The original anything goes game mode was renamed “Anarchy”. Switching from one mode to the other is determined by the users themselves in real-time.
[Devon], one of our readers, has been busy as well. He’s written up a tutorial on turning a Raspberry Pi into a dedicated TPP viewer. We’d love to see a TPP battlestation - a Game Boy modified to display TPP, as well as send commands to the IRC servers when buttons are pressed. Who will be the first reader to knock that hack out?
Filed under: nintendo gameboy hacks
Thursday, February 27, 2014 - 01:00Hackaday 68k: Enclosure, Backplane, And Power
It’s about time for an update for Hackaday’s latest project – a modern retrocomputer based on the Motorola 68000 CPU. In this update, we’ll be taking a look at the enclosure, the backplane itself, and how we’re going to power this thing.
This is only an update to the project; you can check out the current status over on Hackaday Projects. It’s Hackaday’s new collaborative project hosting site where you (and your friends) can design, build, or document anything you have in mind. Request an invite for the alpha release of Hackaday Projects and you can give this project a skull! Seriously, this project is only the third ‘most skulled’ one on Hackaday Projects.
Now that the completely transparent pitch for Hackaday Projects is over with, we can get on to the update for the Hackaday 68k. Click that ‘Read More…’ link.
You don’t build a house by starting with the kitchen cabinets, and like any project this computer needs a good foundation. This means picking out a nice enclosure, figuring out some way to power the thing, and constructing the backplane that will connect all the different cards I’ll be designing and building.
Having a good-looking enclosure shouldn’t be a primary goal for what is really simply a prototype, hacked-together homebrew project, but I have a few special considerations for this project. Firstly, I’ll eventually be lugging this around to hackerspaces, meetups, and Maker Faires. It needs to be secure. Secondly, a lot of people are already following this project on Hackaday and on Hackaday Projects. It needs to look good.
The enclosure I’ve picked out is a beautiful steel instrument enclosure from Hammond. Specifically, the 1458VD4B enclosure, measuring 8x8x4 inches. I love Hammond enclosures, and when I put the top on and screw everything together, it really looks like something from the early 80s.
In the world of backplanes and retrocomputers, power supplies are a bit of a problem. There are very old S-100 bus systems that used huge linear power supplies, with transformers and caps big enough to kill an elephant. That’s not something I want – or could even fit – in an eight-inch square case. Linear supplies are old tech, though. The Apple II and the Digital VT100 terminal – contemporaries of the 68000 – had switching power supplies, but unfortunately they were also huge.
A much better option for providing power to the backplane would be to take a normal PC power supply, add a 24-pin ATX header, and plug everything in. It’s a great idea, but even the smallest computer power supply would eat up a ton of volume in my enclosure.
Here is the solution. It’s called the picoPSU, and it’s barely larger than a standard 20-pin ATX power supply connector. It’ll provide 6A of 5V, and also has 12V, 3.3V, and -12V should I need that in the future. It’ll also power a hard drive, all without requiring any load. This is, by far, the easiest and cheapest way for me to power this computer.
Now we come to the important part of this update. The backplane. The board I’m going to plug the CPU, ROM, RAM, Video, and Ethernet cards into. If the CPU is the brain of a computer, the backplane is the brainstem. If this doesn’t work, nothing will.
Next up are seven Eurocard connectors. These are 64-pin Eurocard connectors, despite there being 96 pins. Only rows A and C (row B is the middle) have pins soldered to the backplane. There’s no logic here, just simple solder traces from one pin to another. If you’re extremely clever, you might be asking yourself why not use 96-pin sockets. I’m going to answer that with another question.
That’s the problem I faced when trying to design a two-layer 96-pin backplane. Why a two layer backplane? Because it’s cheaper. I’m also pretty sure it’s mathematically impossible. Proofs are welcome.
Either way, I don’t need 96 pins on this backplane. 64 pins are enough, once you know what you can safely ignore when designing something with the 68000. I’ll get to that in the next update.
With only seven card connectors, this isn’t a very large backplane. When you consider I’m doing the CPU on one card, RAM on another, ROM on a third, two more for Ethernet and video output, I don’t have much room to work with. From everything you’ve seen so far, there’s not even space for a cool ‘switches and blinkenlights’ front panel
But Wait, There’s More
There’s the front and the back of the backplane showing off a neat little feature I snuck in. I call it a ‘frontplane’, but basically all it does is break out all the signals to a female 0.1″ header socket graciously supplied by Samtec‘s amazing sample request order form. They’re low-profile 0.1″ headers, meaning I can barely squeeze in an additional board between the backplane and the front panel of the enclosure.
What’s that green board, you ask? That’s my first attempt at making an external power switch, power LED, and reset button. Mechanically, this design did not work.The space between the backplane and the front panel of the enclosure is just too tight. This isn’t really a necessary part of the build – I have power and reset switches and buttons on the backplane and CPU board – but it does make it look nice. Right now, the ‘external’ controls for this project have been pushed back to the very end of this project. Or when I get stuck on something. I don’t know.
Other Electronic Considerations
In the first post for this project, a few people asked me how I would be terminating the backplane. Until I get the RAM and ROM working, I don’t know if I need to. I found this app note for RC terminator networks saying the 68000 usually doesn’t need termination on the data, address, or control busses. Don’t get me wrong, I’m going to be taking a scope to this when everything is wired up, but even if I do need termination, I’ll only need a few one dollar parts. It’ll also be a great use for the frontplane.
That’s All For Now
This is the most boring part of the project, I know. Still, it needed to be documented. The next update will more than make up for it. I’ll be going over the 68000 CPU itself, showing off what you can safely ignore, and telling you why designing a computer around the 68k isn’t much more difficult than designing a computer around the old 8-bit CPUs like the 6502. Really, there’s not much to it. Also, blinking LEDs. Yeah!
Here’s the link to the entire project on Hackaday Projects. Rate, comment and subscribe, or something like that.
And yeah, that’s a silkscreen of BMO.
Wednesday, February 26, 2014 - 22:00Improving A Homebrew CT Scanner With Barium
[Peter] has been working on his homebrew CT scanner for a while, and it’s finally become something more than a spinning torus of plywood. He’s managed to image the inside of a few pieces of produce using an off-the-shelf radiation detector and a radioactive barium source
When we last saw [Peter]‘s CT scanner, he had finished the mechanical and electronic part of the Stargate-like device, but the radioactive source was still out of reach. He had initially planned on using either cadmium 109 or barium 133. Both of these presented a few problems for the CT scanner.
The sensor [Peter] is a silicon photodiode high energy particle detector from Radiation Watch this detector was calibrated for cesium with a detection threshold of around 80keV. This just wasn’t sensitive enough to detect 22keV emissions from Cd109, but a small add-on board to the sensor can recalibrate the threshold of the sensor down to the noise floor.
Still, cadmium 109 just wasn’t giving [Peter] the results he wanted, resulting in a switch to barium 133. This was a much hotter source (but still negligible in the grand scheme of radioactivity) that allowed for a much better signal to noise ratio and shorter scans.
With a good source, [Peter] started to acquire some data on the internals of some fruit around his house. It’s still a slow process with very low resolution – the avocado in the pic above has 5mm resolution with an acquisition time of over an hour – but the whole thing works, imaging the internal structure of a bell pepper surprisingly well.
Wednesday, February 26, 2014 - 19:003D Printering: Making A Thing With Solidworks, Part II
Last week we started to Make a Thing in Solidworks. We got as far as sketching and extruding the base. This week we’ll make the back portion. We’ll use some of the same techniques in Part I and a few new features such as 3D filleting and the Hole Wizard.
As you know, this is not the first ‘Making a Thing’ tutorial. In case you missed them, the softwares previously covered in the 3D Printering series are:
- AutoCAD Part I
- AutoCAD Part II
- Blender Part I
- Blender Part II
- Autodesk 123D
- FreeCAD Part I
- FreeCAD Part II
- Solidworks Part I
Picking up where we left off, the next step is to make the back portion of the shape. To do this, start by rotating the view to see the rear face of the part. We want our sketch to be on the rear face so select the rear face by clicking on it. Once it is highlighted, select Sketch from the Sketch Tab.
A new line will show up in the Model Tree (in this case it is called Sketch2). Right click on this and click on the Normal To icon. This will rotate the view to be perpendicular to the face the sketch will be on.
Now that we are looking at the rear face of the part, we can draw the back portion, which is basically a tombstone shape with tapered sides. Start by drawing a circle. It can be any size and any location as it will be dimensioned later. Like in Part 1, I will intentionally sketch the shape out of proportion to show how the geometry will change when adding dimensions and constraints.
The tapered lines should be tangent to circle. To do this, select the Line Tool from the Sketch Tab, start the line on one of the top corners of the rear face. Then hover over the circle near the point where the line would be tangent to the circle. A yellow box with a tangent symbol will appear. Clicking at this time will make the line tangent to the circle. Do this for the other side. Then draw the last 3 lines. Hovering over the corners of the rear face will make the lines snap to those points. On the Sketch Tab, select the Trim Tool and click on the bottom portion of the circle to delete it.
From the sample drawing, we know that the center of the arc is 7/8″ above the top face of the portion we have already drawn and extruded. Use the Smart Dimension Tool to add a dimension from the center of the arc to the top face of the extruded part. Then enter “7/8″ as the desired distance and the sketch will move to satisfy that requirement. Click on the arc to specify its radius. Enter 5/8 or 0.625.
The radius is currently not centered over the rear face. To center it, left click on the top of the rear face and select the midpoint. Then hold shift and select the center of the arc. A window will pop up, select the vertical line to make the arc centered over the rear face.
The sketch is now complete. Click Exit Sketch from the Sketch Tab.
NOTE: The 7/16″ through-hole could have been drawn on the sketch and it would have created a hole when the sketch was extruded. After that, the counterbore would still have to be added. We will create both the hole and counterbore in one step later.
To extrude the part, select the sketch (Sketch2) on the Model Tree, then on the Features Tab, select Extruded Boss. In the Boss-Extrude dialog box, type in 0.5 or 1/2 to specify the length to extrude. Click the green check mark to make it happen.
To make the hole and counterbore we’ll try something new. Select the Hole Wizard from the Features Tab. This tool will allow us to make the hole and counterbore at the same time. In the Hole Specifications Dialog Box, select the following:
Hole Type: Legacy Hole
Type: Counterbored (adds a counterbore)
End Condition: Through All (makes the hole go through the entire part)
Enter the dimensions from the sample drawing for the Hole Diameter, Counterbore Diameter and Counterbore Depth.
NOTE: We can’t change the hole Depth because we specified “Through All” for the End Condition. If we selected “Blind” and added a depth of 2 inches, the hole would go into the part 2 inches deep.
Now that the hole and counterbore dimensions are specified, we need to determine where the hole will be. While still in the Hole Specifications dialog box, click on the Positions Tab. Then select the face of the part where the hole will be placed. Position does not mater right now.
A representation of the counterbored hole will be placed on the part. We know it is not in the correct spot. To make the hole concentric with the arc of the back portion of the part, click on the asterisk at the center of the previewed hole, then hold shift and click on the arc of the part. A little window will pop up. Clicking on the icon made of two circles will make the two selected features concentric with one another. Hit the green check mark to finish the operation.
Remember in Part 1, we left a couple fillets off of the drawing so that we could add them later. On the Features Tab, there is a Fillet Tool. Selecting this will open a dialog box where you can enter the desired radius of the fillet. The sample drawing stated these fillets were 1/8 inch. Enter that and click on the corners that need to be radiused. Solidworks will show a preview of the fillets. Click the green check mark to accept the preview.
That’s it! Here’s the final product:
This Hackaday Column is called 3D Printering and in order to print the part, the file must be saved in .stl format. This is as easy as File-Save As. Select .stl from the file type list.
That concludes the Solidworks ‘Making A Thing’ tutorial. Happy modeling and printing!
Filed under: Hackaday Columns
Wednesday, February 26, 2014 - 16:00Wireless AC Control With The Raspberry Pi
We’ve seen some of [Connor]‘s work before, and it looks like he’s now turning to product design. He’s come up with an adapter for the Raspberry Pi to control a few wireless wall socket relays, allowing anyone with a Pi to control lights, coffee makers, TVs, and anything else that falls under the very broad home automation banner.
The system uses a 315MHz radio breakout board for a Raspberry Pi to control the relays in one of three wall socket adapters. There’s a script running on the Pi with a very nice GUI to turn the lights on and off.
[Connor]‘s product is extremely similar to a certain WiFi-enabled wall-plug relay system controlled by a smartphone, and to that end, he’s decided to call his device the Belchin’ Emo Switch. The name might need work, but he’s selling three Raspberry Pi-controlled wall plugs for the same price of one wall plug from Brand A.
Below you’ll find [Connor]‘s videos for his device. You can also check out this reddit thread where he shows off just how open source he can be; there are part suppliers and even how he’s packaging this system for shipment.
Filed under: Raspberry Pi
Wednesday, February 26, 2014 - 13:00Get Your Hackerspace A 3D Printer
LulzBot is yet again giving away a few of their very fancy and well-reviewed 3D printers away to a few hackerspaces.
This isn’t the first time LulzBot has given away a few of their printers; a year and a half ago, they gave away eight AO-100 printers and they also donated one to our ‘ol buddy [Caleb] for TheControllerProject, a forum to connect disabled gamers to people who have the means and ability to make custom gaming controllers.
The rules for this giveaway are simple: Be a hackerspace, and display, “creativity and contributions to the free software and open hardware community.” It’s as simple as that. If you’re a hackerspace without a 3D printer – which would be somewhat astounding at this point – here’s your chance to get one of the best 3D printers around.
The contest will be open starting March 1 and ends on March 14, with entry requiring a hackerspace fill out a form somewhere on the LulzBot servers.
Filed under: news
Wednesday, February 26, 2014 - 10:00Confuse the Birds with this Daylight Simulation System
Hackers love a challenge. So when [Patrick's] father-in-law asked him to look into a daylight simulation system for his bird breeding cages, [Patrick] quickly discovered the ridiculous prices for commercial systems… so he convinced his father-in-law to let him design and build one instead.
Like any project, [Patrick] quickly listed the requirements of the system before starting anything.
- It must brighten gradually in the morning
- Stay constant throughout the day
- Dim in the evening to a very low intensity
In addition to this, the lighting transition should be smooth, and the lights cannot flicker, as this can be stressful for the birds — oh, and it needs to be reliable.
To build the system, [Patrick] has chosen an Arduino Duemillenova, an RTC, a small LCD screen, some cheap LEDs from eBay and a handful of N-channel NPN transistors to provide the PWM for the LEDs. The entire system cost less than $100 — a much cheaper alternative to commercial systems.
We think the system looks great, but as a big fan of the Hack a Day community, [Patrick] would love to hear your feedback!