They say that necessity is the “Mother of Invention”, but over the years we’ve started to suspect that her cousin might be an underutilized microcontroller. How else can you explain projects like the latest from [MN Maker], which takes the relatively simple concept of a contact lens holder and manages to turn it into an Internet-connected electronic appliance? Not that we’re complaining, of course.
He started out with a simple 3D printed holder for his wall that would let him pull out his daily lenses, which worked well enough and gained some popularity on Thingiverse. But he wondered if there wasn’t some way he could use a servo to automate the process. While he was at it, he might as well play with some of the components he’s been meaning to get some hands-on experience with, such as those little OLED displays all the cool kids are using.
Modifying his original design to incorporate servos in the bottom, he added a central compartment that would house an ESP8266 and a simple proximity sensor made from an IR LED and photodiode. The sensor tends to be a little twitchy, so he left a potentiometer inside the device so he can fine tune it as needed.
Strictly speaking the OLED display isn’t actually required for this project, but since he had a WiFi capable microcontroller sitting there doing basically nothing all day anyway, he added in a feature that shows the weather forecast. It’s not much of a stretch to say that the first thing you’d want to see in the morning after regaining the sense of sight is a readout of what the day’s weather will be, so we think it’s a fairly logical extension of the core functionality. Bonus points if he eventually adds in a notification to remind him it’s time to order more lenses when the dispenser starts getting low.
If you don’t have any contact lenses you need dispensed, never fear. A similar concept can be used to fire off your customized swag at hacker events. Don’t have any of that either? Well in that case you can always build a candy dispenser for Halloween.
Continue reading “A Contact Lens Launcher that Knows the Weather”
The ocean is a hostile environment for man-made equipment, no matter its purpose. Whether commercial fishing, scientific research, or military operations, salt water is constantly working to break them all down. The ocean is also home to organisms well-adapted to their environment so DARPA is curious if we can leverage their innate ability to survive. The Persistent Aquatic Living Sensors (yes, our ocean PALS) program is asking for creative ideas on how to use sea life to monitor ocean activity.
Its basic idea is simple: everyday business of life in the ocean are occasionally interrupted by a ship, a submarine, or some other human activity. If this interruption can be inferred from sea life response, getting that data could be much less expensive than building sensors to monitor such activity directly. Everyone who applies to this research program will have the chance to present their own ideas on how to turn this idea into reality.
The program announced it will “study natural and modified organisms” (emphasis ours.) Keeping an open mind to bio-engineering ideas will be interesting, but adding biohacking to the equation also adds to the list of potential problems. While PALS will keep its research within contained facilities, any future military deployment obviously will not. Successful developments in this area will certainly raise eyebrows and face resistance against moving beyond the lab.
But such possibilities are still far away in a future that many never arrive, as is common with DARPA initiatives. Very recently we talked about their interest in brain stimulation and we’ve been fascinated by many DARPA initiatives before that. If PALS takes off, their living sensor nodes might end up face to face with the open-source underwater glider project that won this year’s Hackaday prize.
The proliferation of breakout boards that the DIY electronics movement has allowed has been staggering. Buy a few different boards, wire them together to a microcontroller or credit-card computer (both on their own breakout board) and write a bit of code, and you can create some really interesting things. Take Reddit user [Lord_of_Bone]’s Nerf Gun ammo counter and range finder, for example, a great example of having a great idea and looking around for the ways to implement it.
For the range finder, [Lord_of_Bone] looked to an ultrasonic rangefinder. For the ammo counter, [Lord_of_Bone] chose a proximity sensor. To run everything, the Raspberry Pi Zero was used and the visuals were supplied by a Rainbow Hat. The range finder is self-explanatory. The proximity sensor is located at the end of the gun’s muzzle and when it detects a Nerf dart passing by it reduces the ammo count by one. Blu-tack is used to hold everything in place, but [Lord_of_Bone] plans to use Sugru when he’s past the prototype stage.
The one problem [Lord_of_Bone] has with the build is that there’s no way to tell how many Nerf bullets are in the magazine. Currently the wielder must push a button when reloading to reset the count to a preset amount. We’re sure that [Lord_of_Bone] would appreciate any suggestions the Hack-A-Day crowd could offer.
[Lord_of_Bone] gives a full bill of materials, Python code, a lot of pictures and step-by-step instructions so that you, too, can determine how far away your target is, and whether or not you have enough ammo to hit them. We have quite a few Nerf mods on the site, and [Lord_of_Bone] could take a look at this article about how to keep track of your Nerf ammo, and here’s a different method of determining if a Nerf dart has been fired (and measuring its speed.)
[via Reddit] Continue reading “Nerf Gun Ammo Counter and Range Finder”
The wood router is a versatile power tool which can be picked up at a low price. Nicer router setups are mounted underneath a table, with the cutting head poking through. This makes it easier and safer to work with the tool.
[Paul] combined his interest in electronics and woodworking by making a router table with automated controls [translation]. The neat part of this build is the automated height control, which ensures accurate cutting depth.
The router is mounted to a threaded rod, which allows it to be moved up and down by a motor. A low cost L298 motor driver provides the power to the motor, which is controlled by an Arduino Uno. A VCNL4020 based sensor board is used to measure distance and accurately set the router height. This tiny proximity sensor looks like a nifty chip, providing distance measurements up to 200 mm and an ambient light sensor in one package.
The routing table has an LCD display and buttons, allowing the user to dial in their desired height. The entire thing was built using recycled bits and well under $100 in new parts.
A team of students from Cornell University are looking into alternative ways of creating a security system that can be locked or unlocked by using physical gestures in an enclosed space.
It is the final year project for [Ankur], [Darshan] and [Saisrinivasan] in their MEng of Electrical and Computer Engineering. The system prototype is capable of recording a gesture and then comparing the gesture with future gestures to lock or unlock the system. Consider it like a secret handshake to get into the office!
To analyze the gesture they are using four SparkFun proximity sensors setup in a linear array to sense the distance a hand is moved. An ATMega1284P is used to convert the analog sensor signal to digital for further processing. The project is extremely well documented, as it appears to be the final report for the project.
A short video after the break shows off the prototype and gives a good explanation of how the system works.
Continue reading “Gesture Based Security Lock”
This pair of musical keyboard hacks both use light to detect inputs. The pair of tips came in on the same day, which sparks talk of consipiracy theory here at Hackaday. Something in the weather must influence what types of projects people take on because we frequently see trends like this one. Video of both projects is embedded after the jump.
On the left is a light-sensitive keyboard which [Kaziem] is showing off. In this image he’s rolling a marble around on the surface. As it passes over the Cadmium Sulfide sensors (which are arranged in the pattern of white and black keys from a piano keyboard) the instrument plays pitches based on the changing light levels. [Thanks Michael via Make]
To the right is [Lex’s] proximity sensor keyboard. It uses a half-dozen Infrared proximity sensor which pick up reflected light. He calls it a ‘quantised theremin’ and after seeing it in action we understand why. The overclocked Raspberry Pi playing the tones reacts differently based on distance from the keyboard itself, and hand alignment with the different sensors.
Continue reading “Pair of musical hacks use sensor arrays as keyboards”
[Dustin Andrews] built this add-on board which works as a proximity sensor. He wanted a standalone sensor for his Arduino projects which would use a single pin as a trigger. This lets him alert the Arduino when an object approaches the sensor without the need for polling or extra code on the Arduino side of things.
As you can see, a single chip on the board takes care of all the work. That’s an ATtiny13, they’re inexpensive and sometimes you can even salvage them from consumer electronics like this color changing light bulb. The microcontroller monitors the phototransistor which is wrapped in electrical tape to isolate it from the IR LED emitters on either side. This setup creates a reflective sensor. When an object nears the board, the infrared light from the emitters reflects off of it and onto the phototransistor. And since the Arduino works as an AVR programmer you don’t need special hardware to program the device.