I have my Pi hooked up to an LED strip in my room. It is running a flask server so I can control the light with a website or with my Alexa. I use it everyday and it was super easy to set up.
Ask HN: Share Your Raspberry Pi Project
61–70 of 160 posts
Re: Ask HN: Share Your Raspberry Pi Project
#62Recreating the Sony Aibo robot dog using a pile of cheap servos, 3 axis gyro, the camera, wireless, neopixel lights, LiIon power, etc. Shoulder joints, body shell and chassis 3d printed. Total cost is around $150. Locomotion is largely based upon the designs documented by Cynthia Brezeal Ferrell (MIT mobile robots lab, under Prof. Rod Brooks) in her PhD thesis for the hexapod robot, Atilla/Hannibal. The first attempt…
Could you share more about your experience with elastic actuators? What did your hardware look like? I'm working on something similar, and would love your input.
Sure. It's an evolution of the idea I saw here:
http://hackaday.com/2015/12/15/feeling-force-through-a-servo...
Using a flexible servo horn, this allows some degree of deformation when torque is applied. Embed a 1/32" neodymium magnet in the horn, and a magnetic rotary position sensor in the driven part. As resistance to movement ("torque") increases, the flexible servo horn twists/deflects, angle of difference between the two parts changes and this can be detected by the magnetic sensor.
Picture a torque strain gauge, the way the needle deflects from the centerline of the gauge. This is similar but we're doing so in an radial (edit:removed axial) and not linear sense.
I went on to 3d print a flexible servo horn somewhat similar to this: http://mechanismsrobotics.asmedigitalcollection.asme.org/dat... but with the magnet embedded in the outer rim of the wheel and the sensor in the inner section.
Different amounts of sensitivity are obtained by printing different spoke stiffness on the horn.
Result is a compact, modular torque sensor for about $2 in parts. Feed the results to a PID look and you have a nice controller that can tell me when a robot leg is bearing a load, or is jammed, etc. This is essential to proper gait. Otherwise your robot is simply an electronic marionette.
One of the big challenges was getting 16 additional 16bit voltage reads back to my Rpi over i2c bus. (one value for each servo) https://www.adafruit.com/product/1085
Soln: used one of these multiplexer boards: https://www.adafruit.com/product/2717
and I used AdaFruit's excellent servo controller board: https://www.adafruit.com/product/815
and some neopixel rings for eyes: https://www.adafruit.com/product/3047
(wonderful for expressing mood)
Re: Ask HN: Share Your Raspberry Pi Project
#63Although not strictly a Raspberry Pi project, I have a couple C.H.I.P. boards[1] scattered throughout my apartment collecting temperature and humidity readings (using a HIH8120 sensor[2]) and feeding it to my Raspberry Pi which runs InfluxDB and Chronograf[3] to store and display a simple dashboard. The end result looks like this: http://i.imgur.com/cIrhSUq.png [1]: https://getchip.com/ [2]: https://sensing.honeywell…
What language did you end up using to access the sensors?
I've been ~hoping~ to use Go to access the GPIO pins, but haven't had much success - any suggestions?
Re: Ask HN: Share Your Raspberry Pi Project
#64Earlier quoted context omitted.
Could you share more about your experience with elastic actuators? What did your hardware look like? I'm working on something similar, and would love your input.
Sure. It's an evolution of the idea I saw here: http://hackaday.com/2015/12/15/feeling-force-through-a-servo... Using a flexible servo horn, this allows some degree of deformation when torque is applied. Embed a 1/32" neodymium magnet in the horn, and a magnetic rotary position sensor in the driven part. As resistance to movement ("torque") increases, the flexible servo horn twists/deflects, angle of difference betwe…
This is great, thank you!
Re: Ask HN: Share Your Raspberry Pi Project
#65I used one to build a photobooth for my wedding. The raspberry pi controls a DSLR camera to take 4 photos, stitches them into a 4x6, prints the photo and uploads everything to a Google Photos album which was displayed live on a projector.
I've been looking to do this myself, did you follow any guides online to help you with this? How did you connect your camera to the Pi?
Re: Ask HN: Share Your Raspberry Pi Project
#66I built a tube internet radio with speech output of station names and switching stations with the AM dial. A small USB mouse picks up the rotation, a python script speaks the station name and passes the stream URL to gmediarenderer. Sound via USB soundcard and Phono/Aux input. Inspired by http://blog.scphillips.com/posts/2014/05/playing-music-on-a-... . Some pictures at http://imgur.com/a/r834D
Any info re: interfacing with the dial? I bought a radio for a similar purpose that's just been gathering dust in the garage.
Re: Ask HN: Share Your Raspberry Pi Project
#671. use it as a weather station - temp/hum/pressure sensors are quite cheap
2. if you already have weather station, hook it up to an API and share the data (wunderground.com, or similar)
3. you can use it as local lan media player/web server if you don't want to mess with hardware
4. build a bad ass robot/drone/submarine with it
5. build security system - possibilities are limitless. You can even use pressure sensor as intrussion detection device, let alone sound, light, shock, camera, IR, etc sensors....
6. use it as an alarm clock
7. use it as decoration - if you need it to last forever, pour a resin in a mould over it
8. wrap it as a gift if everything else fails
Re: Ask HN: Share Your Raspberry Pi Project
#68A friend and I put together a free dynamic DNS service [1] offering cool custom domains aimed at the Raspberry Pi community (and similar hardware hackers.)
It's not strictly a hardware project, but it's a crucial building block for any network-enabled Raspberry Pi project, and we'd love your feedback.
Re: Ask HN: Share Your Raspberry Pi Project
#69Maybe not useful (to anyone else at least), but I've built a couple of small wheeled robots with cameras to do some experiments with Computer Vision.
Unless you're doing computationally intensive tasks, I find a Raspberry Pi 3 is overkill. If you go with the cheaper models like one of the low end Orange Pi's, you don't mind dedicating them to projects, even if the project is pretty useless.
Re: Ask HN: Share Your Raspberry Pi Project
#70I'm working on simplifying live streaming from the Raspberry Pi to Periscope [1] using the Camera Module [2]. Future streaming targets include the usual suspects: Twitch, YouTube, Facebook Live, et al. Deployment is flexible; you can install it as a Debian package, a Docker image, or a standalone binary.
Personally, I plan to use it as a traffic camera mounted on the window of our office.