[Adnan.R.Khan] had a sliding door latch plus an Arduino, and hacked together this cool but simple app controlled door lock.

Mechanically the lock consists of a Solarbotics GM3 motor, some Meccano, and a servo arm. A string is tied between two pulleys and looped around the slide of a barrel latch. When the motor moves back and forth it’s enough to slide the lock in and out. Electronically an Arduino and a Bluetooth module provide the electronics. The system runs from a 9V battery, and we’re interested to know whether there were any tricks pulled to make the battery last.

The system’s software is a simple program built in MIT App Inventor. Still, it’s pretty cool that you can get functionally close to a production product with parts that are very much lying around. It also makes us think of maybe keeping our childhood Meccano sets a little closer to the bench!

There have been a lot of smart computers on TV and movies. We often think among the smartest, though, are the ones on Star Trek. Not the big “library computer” and not the little silver portable computers. No, the smart computers on Star Trek ran the doors. If you ever watch, the doors seem to know the difference between someone walking towards it, versus someone flying towards it in the middle of a fist fight. It also seems to know when more people are en route to the door.

Granted, the reason they are so smart is that the doors really have a human operating them. For the real fan, though, you can buy a little gadget that looks like an intercom panel from the Enterprise. That would be cool enough, but this one has sound effects and can sense when someone walks into your doorway so they can hear the comforting woosh of a turbolift door.

Of course, for the real hacker, that’s not good enough either. [Evan] started with this $25 gadget, but wanted to control it with an Arduino for inclusion in his hackerspace’s pneumatic door system. He did a bit of reverse engineering, a bit of coding, and he wound up in complete control of the device.

The internals of the device were mostly straightforward with some PIR sensors, switches, LEDs, and some epoxy blobs that produce the sound and control the logic. [Evan] had to be a little creative since the red alert sound, once started, would not stop for some time. The solution? Let the Arduino cut power to the board when it wants silence.

The code is available on GitHub. There were a few other tricks required, including removing a PIR sensor chip and adding a USB to serial adapter. Once you can treat the whole thing as an I/O device, you could probably do a lot of interesting projects easily. And of course, this sort of offering would be perfect as an entry in the Hackaday Sci-Fi contest.

For some reason, we don’t see as many original series hacks as we do for the Next Generation. We have, though, seen at least one other swoosh door. On the other hand, if you fly against that door while being thrown by a Captain Kirk style body slam the door will still open. We can’t vouch for it, but this video has an interesting analysis of the door noise that reminded us of a modern version of playing our old LPs backward.

Who doesn’t like the user interface in the movie Minority Report where [Tom Cruise] manipulates a giant computer screen by just waving his hands in front of it? [AdhamN] wanted to unlock his door with hand gestures. While it isn’t as seamless as [Tom’s] Hollywood interface, it manages to do the job. You just have to hold on to your smartphone while you gesture.

The project uses an Arduino and a servo motor to move a bolt back and forth. The gesture part requires a 1sheeld board. This is a board that interfaces to a phone and allows you to use its capabilities (in this case, the accelerometer) from your Arduino program.

The rest should be obvious. The 1sheeld reads the accelerometer data and when it sees the right gesture, it operates the servo. It would be interesting to do this with a smart watch, which would perhaps look a little less obvious.

We covered the 1sheeld board awhile back. Of course, you could also use NFC or some other sensor technology to trigger the mechanism. You can find a video that describes the 1sheeld below.

In order to resolve the problem of congestion at the entrance to their hackerspace, the minds at i3Detroit installed a motion-activated mechanical iris in their door’s porthole.

Grabbing the design online (which they are now hosting on their site here), the parts were laser cut out of wood, gold leaf was added for effect, and it was relatively easy to assemble. PIR sensors detect movement on both sides of the door and an FET resistor connected to an orange LED add some old-school science fiction flair. The iris is actuated by a 12V car window motor — which works just fine on the 5V power that it’s supplied with — and an Arduino filling in as a controller. Start and stop positioning required some limit switches that seem to do the trick.

Finally they laser cut acrylic plastic with the i3Detroit logo to complete the porthole modification. You can watch a video of the mechanical iris in all its glory here — but unfortunately it’s on Google+ (do people still use that??) so we can’t embed it in the post.

If you want to add this sleek idea to your home but lack a laser cutter (understandable), then you can still hack one out of some common household materials.

[via Evan’s Techie-Blog]

We have a pretty good guess where [Krizbleen] hides away any seasonal presents for his family: behind his shiny new secret library door. An experienced woodworker, [Krizbleen] was in the process of finishing the attic in his home when he decided to take advantage of the chimney’s otherwise annoying placement in front of his soon-to-be office. He built a false wall in front of the central chimney obstacle and placed a TV in the middle of the wall (directly in front of the chimney) flanked on either side by a bookcase.

If you touch the secret book or knock out the secret sequence, however, the right-side bookcase slides gently out of the way to reveal [Krizbleen’s] home office. Behind the scenes, a heavy duty linear actuator pushes or pulls the door as necessary, onto which [Krizbleen] expertly mounted the bookcase with some 2″ caster wheels. The actuator expects +24V or -24V to send it moving in one of its two directions, so the Arduino Uno needed a couple of relays to handle the voltage difference.

The effort spent here was immense, but the result is seamless. After borrowing a knock-detection script and hooking up a secondary access button concealed in a book, [Krizbleen] had the secret door he’d always wanted: albeit maybe a bit slow to open and close. You can see a video of its operation below.

Do you need to build a KeyPad for your system? [AverageGuy] did it himself. Here his story:

My old keypad GDO gave up the ghost a while back so I decided I’d undertake a new Arduino based project. I saw there were quite a number of wireless projects already and one wired, but the wired on didn’t go into any detail, so here’s an incomplete implementation. Food for thought if nothing else.

On the [website] there is a full description and the schematics. I really recommend you if you’re interested, because the explanation is complete in every aspects.

[Steve] is often host to all sorts of guests, and he was looking for an easy way to let his friends come and go as they please. After discovering that his front door came equipped with an electronic strike, he decided that an RFID reader would be a great means of controlling who was let in, and when.

Giving all your friends RFID cards and actually expecting that they carry them is a bit of a stretch, but lucky for [Steve] he lives near Boston, so the MBTA has him covered. Just about everyone in town has an RFID subway pass, which pretty much guarantees that [Steve’s] cohorts will be carrying one when they swing by.

He crafted a stylish set of wooden boxes to contain both the RFID reader and the Arduino that controls the system, matching them to the Victorian styling of his home. A single button can control the setup, allowing him to add and remove cards from access lists without much fuss. For more granular control however, [Steve] can always tweak settings from the Arduino serial console.

The card system is both stylish and useful – a combination that’s hard to beat.

Who hasn’t dreamed of have a Star Trek style automatic door in their home (complete with “wooshing” noise)? Now you can build your own with the help of this DIY project and some pneumatics. The pnematic system uses an air compressor, a piston, valves, hoses, infrared sensors, and an Arduino.  The best part about the pneumatics is that the “woosh” noise comes built in – No special effects department needed!  Check out more details about the door.

Popular Star Trek Projects:

• A Similar Pneumatic Star Trek Door
• Star Trek Inspired Touchscreen Kitchen Interface
• Star Trek U.S.S. Enterprise Submarine!