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Ask HN: Share Your Raspberry Pi Project

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21–30 of 160 posts

Re: Ask HN: Share Your Raspberry Pi Project

#21
Just yesterday I used an old raspberry pi to make a bluetooth audio receiver that could be integrated with my vintage stereo equipment. You can buy something off the shelf for around $25 but they use cheap digital-to-analog converters and I wanted to use the high quality USB DAC I already had. Total hardware needed was the Pi, powered USB hub, USB DAC, and USB bluetooth adapter.

Potato quality photo of the very advanced system I came up with for keeping all the components together: https://tootcatapril2017.s3-us-west-2.amazonaws.com/media_at...

Re: Ask HN: Share Your Raspberry Pi Project

#22
Recreating 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 was using Python which presented two insurmountable problems : 1) raspian OS boot time of 1.5 minutes which is unacceptable for an embedded device and 2) python threading is not sufficient for realtime. I was attempting to make series elastic actuators but the imprecision of the threading (jitter) was leading to wild oscillations... I finally had to accept it was a dead end.

I have started over in Elixir + Nerves which is designed at its core for embedded work. I will admit it is very slow going. Not because of any deficiencies in the language or environment. Quite the contrary -- I get a 10-second cold boot time and superb stability! But rather my mind is the limiting factor here. After three decades of imperative programming, the shift to functional programming is a challenge!

Re: Ask HN: Share Your Raspberry Pi Project

#24

I have one running a few home automation type tasks (an IP->serial gateway for my whole-house audio, SDR radio to monitor 4 utility meters [only 2 meters are currently reporting data as my 2 water meters are not reporting usage via radio to me or to the utility], and controlling relays for the sprinkler system). Next steps are I plan to create an Alexa skill that will control the whole-house audio and let me "pause"…

Curious about your SDR meter monitoring. Any links or description of how that works? Would love to monitor my electric and water without using the energy company's devices.

Re: Ask HN: Share Your Raspberry Pi Project

#25
Although 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.com/HIH8120-021-001S-humidity-sens...

[3]: https://www.influxdata.com/time-series-platform/chronograf/

Re: Ask HN: Share Your Raspberry Pi Project

#27

Recreating 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…

Any pictures, write up, Github? This sounds awesome!

I also remember reading awhile back about the huge market for upkeeping these things once Sony abandoned it. Perhaps you're onto a business!

Re: Ask HN: Share Your Raspberry Pi Project

#29
Use Home Assistant to integrate anything in your house. Make voice assistants respond to your commands. Write advanced automations to help make your life easier.

Use our Hass.io OS build to setup Google Assistant easily on your Pi. Need a USB microphone and speakers connected to the Pi and you'll get the full Google Assistant experience.

https://home-assistant.io

(disclaimer: I'm the founder)

Re: Ask HN: Share Your Raspberry Pi Project

#30

I have one running a few home automation type tasks (an IP->serial gateway for my whole-house audio, SDR radio to monitor 4 utility meters [only 2 meters are currently reporting data as my 2 water meters are not reporting usage via radio to me or to the utility], and controlling relays for the sprinkler system). Next steps are I plan to create an Alexa skill that will control the whole-house audio and let me "pause"…

Curious about your SDR meter monitoring. Any links or description of how that works? Would love to monitor my electric and water without using the energy company's devices.

I didn't do any actual hard work. I just used rtl-amr, which was super-easy to grab, compile, and use.

http://bemasher.net/rtlamr/

http://bemasher.net/rtlamr/signal.html has information on how it works, but you don't need to do/know anything about the protocol to get it to work.

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