[Kyle Fredericks] tipped us about his first electronics project, a cheap and smart sleep mask that uses a vibration sensor to detect rapid eye movements.
As some of you may know, REM sleep is the part where you dream the most vividly and actively. If some external stimulation (sound, movement) is sent to you at this moment, it may help you take control of your dream by becoming aware of it. If not, your brain will create dream scenarios that incorporate this stimulus.
The interesting part of the concept is that the vibration sensor calibrates itself at the stage 2 sleep, when no eye movement occurs. This later allows a very accurate detection of the REM sleep stage, triggering a shelf stereo. Secondary buttons are even included in the mask sides.
[Kyle Fredericks] went to great lengths to document every step of the project, making it a perfect first step to learn electronics for beginners out there.
[Viktor] dredged up a hack he pulled off years ago. His grandfather likes to end the day in front of the TV, but he falls asleep soon after sitting down. Rather than tick away the electricity meter all night, [Viktor] built an automatic shutoff which is akin to a modern TV’s sleep feature.
At the time microcontrollers were not as easy to source as they are now. So [Viktor] used a circuit based on the 7400 family of logic chips. It uses a multivibrator to feed some binary counter chips. These are used to divide the oscillations to establish the desired timing. He tuned the system to be about 15 minutes, but that can be adjusted using a potentiometer built into the multivibrator. When time is about the run out an LED next to the TV comes on. This way if [Viktor’s] grandfather is still awake he can press a button next to his chair to reset the counter. But if he’s already snoozing the counter will eventually switch off the television.
This is the desktop binary clock which [Tim the Floating Wombat] recently finished building. He calls it the Obfuscating Chronoscope since it’s a bit more difficult to read than your traditional analog or digital timepieces. But the simple design looks neat and it’s a great way to learn about board layout and microcontroller code.
He started by solving a few questions about the display technique. He wanted to use as few LEDs as possible. He settled on just four, and to prevent unnecessary confusion, decided to make sure each type of display (seconds, minutes, hours) would have at least one LED on at a time. Hours are easy enough to display, but with just four bits how can minutes be shown? He uses a 5-minute resolution, always rounding up to the next division of five. This way the first bit will be illuminated on the hour.
A PIC 24F16KA102 microcontroller keeps time using its built-in RTC and a clock crystal. It puts itself into deep sleep mode after displaying the time. The black knob at the bottom is a push-button which resets the chip, waking it up just long enough show the time once again.
Here’s an effort to make a cheap lucid dreaming mask that is also comfortable. The idea is in response to the goggles we saw in April (which would not be too comfortable to sleep in) and the wildly successful Remee (which has an $80 target price).
The mask itself is sewn from a child’s fleece blanket. Inside is a piece of foam cut from some recreation mat. You know, those squares made for a play area that connect together like a jigsaw puzzle. You may have already spotted the Arduino in the image above, but the project is designed to run from an AVR chip embedded in the foam. The design only uses three LEDs, which may or may not work for you — we’d guess it depends on how they line up with your eyes. The video after the break does a great job of illustrating each point in the construction.
If you’re looking for something less soothing and more recreational you could always try out these trippy goggles.
Continue reading “Lucid dreaming mask marries economy with comfort”
This hardware is used to keep a computer monitor awake when there is motion in the room. The monitor displays important information for firefighter in the vehicle bay, but only needs to be on when they are getting ready to go out on a call. The solution is a simple one, a PIR sensor combines with a mouse for motion sensitive input. When the PIR sensor detects motion it causes a mouse button click via a 2N3904 transistor. Now the monitor will not waste power or have burn-in over the long term, but whenever someone is in the room it will be displaying the information that the emergency workers need to know.
What can you do to make sure your system is running as efficiently as possible? Take a page out of [Mux’s] book, who went to great lengths to measure and adjust his system for ultimate efficiency (translated). What he ended up with is 8.5 Watts of consumption at idle and about 50 Watts under load. Luckily he posted a six-part series with all of the details.
Some of the changes he made were in software, like reducing voltage to certain hardware by adjusting BIOS settings, and installing display drivers that put the screen into the proper sleep mode. Others were hardware changes like swapping out the power supply with a hacked PicoPSU and removing unnecessary parts from the motherboard like the MAX232 com-port chip. Looks like we need to audit our always-on MythTV box and see if we can apply any of these power-saving techniques.
[Mike Silverman] rigged up a way to make his monitor sleep from an iPhone. Working with a Windows system, he installed QuickPHP and NirCmd to add PHP and command line controls. Some quick PHP code writing and this has the effect of creating a sleep button toggled via a network address. He loads up the IP and port information in the Safari browser of his iPhone, creating a Home Screen short cut seen in the image above. Now he clicks on the button and puts the screen to sleep.
It’s not that we find this functionality useful since most monitors sleep after a few minutes of inactivity. But we like the methodology and you can bet we’re already planning uses for this. Any PHP server (like the copy of Apache running on this machine) will do as long as it’s on the same LAN as the iPhone’s WiFi connection.