With Instructables you can share what you make with the world, and tap into an ever-growing community of creative experts.
Interesting info! The high voltage warning is there because the particular valve used for this project requires interfacing w/ household AC voltage, whether through a transformer or some other means. Even if 24VAC isn't enough to break skin resistance, that amount of current is still dangerous and there's always the possibility of shorts. It's always always always important to encourage safety and caution.
Make a Light-Up Holiday Card!View Instructable »
Make a Sneaky Wearable 'Sta...View Instructable »
Good question! The simple resistor-capacitor ("RC") circuit is used to measure changes in the capacitance of the soil moisture sensor. The RPi logs the time constant of the circuit (aka how long it takes to charge the capacitor) which changes depending on moisture and the resistor needs to be large enough to be able to see those small changes. Hope that helps!
Yes, this particular soil moisture sensor is a co-planar capacitor. If your soil moisture sensor is putting out voltage, it is not just the sensor but includes additional circuit components. If you're having trouble calibrating it or whatnot, I'd suggest doing a search in Google for the specific sensor you are using and then reading up on it. You could also do what I did to try and calibrate my sensor -- bake some soil in the oven to get all the moisture out, then all small volumes of water and make readings over time. Takes a loooong time but it's not terribly difficult.
Thank you! Glad you found it useful! 200 kg equates to about 440 lbs, so my initial thought was that with even weight distribution across 4 load cells you could put as much as 4 * 440lbs = 1760 lbs, so theoretically it should be able to handle 1700 lbs. Since 1 ton is ~ 2000 lbs, the post would likely be a bit much with this first design. But! You can definitely use geometry w/ some levers to reduce the weight distribution even further, which is how bathroom scales work. Hope this helps, LMK if you have any other questions! :D
lolol thank you, he's a pretty entertaining pooch ^.^
Build an IoT Industrial Scale!View Instructable »
Make Custom (& Inexpensive)...View Instructable »
Whoa, polymagnets sound incredible! Will definitely have to look into those. Thanks for sharing! :D
Ahhh interesting twist! That's a great idea! I'll definitely try that if it proves to be too difficult to walk. Gotta finish some paid gigs before getting back to the magnetic boots but super excited to try them out! :D
To remotely and automatically turn the water on and off!
Thanks very much! Great question! In terms of polarity, the thin, circular magnets are ideal because the magnetic field is strongest on the surface rather than the side, so you can get them pretty close together without them repelling each other. Had some issues w/ this when I was using thick, rectangular magnets.
Yea, lots of peeps have sent me Colin Furze's project. I'm purposefully avoiding permanent magnets for a variety of reasons. I've incorporated some aspects into my design to deal with the force of permanent magnets, will see how it works in the final test!
lol no plans to kill myself in testing. Fortunately, I'm a rock climber and my partner is a parkour expert, so between the two of us I think we can pull it off (pun intended lol).
By torquing it (aka pulling up on one side of the shoe) -- perpendicular force is super strong but the shear force is pretty weak, so you can effectively "peel" it off.
Awesome! Thanks for the heads up! Ah, yea, lol, seems like everybody has an opinion on how to build it, but that's the point of a tutorial: go and build it!
Who DOESN'T want to walk upside down???!!!!???!? Jeez, debbie downer, You need more wonder and imagination in your life!
Thanks for sharing! One of my friends sent me that also, ha. I want to avoid using electricity since the boots are mostly for outdoor use, but if the magnets don't end up working how I want them to I might try electromagnets.
Ha, thank you very much! :D Seriously, insanely fun!In terms of stepping, that was the goal w/ the large number of small magnets vs. one (or just a few) super strong magnets. Also works better since the force is distributed across a larger surface area.The washers also help keep them together if they do break (although hoping it doesn't come to that, lol). Since they are distributed along the foot, you can "peel" them off by pulling on one part of the shoe, just like how your foot moves while walking. It works pretty well by hand, haven't tested by foot since I'm looking for a safe spot to test upside down.. will definitely figure this out in the final version!
Thanks for the suggestion! Thought about doing the whole electromagnetic thing.. since it's primarily for the outdoors, I wanted to avoid using electricity, but I might try it out for a version 3.0!
Prototyping Magnetic Boots!View Instructable »
Glad to hear you got the hardware working! If you are looking to hire me as a contractor I'm happy to write the program code for you, otherwise you'll have to tackle in on your own. I'm crazy busy and unfortunately can't take on any more uncompensated projects.
Hello! Re: pump, check the specs on the pressure inflow/outflow and make sure it can handle whatever water source you are trying to control. Standard outdoor hose spigots in the US are pretty high pressure, 40 - 60 psi. If your pump can handle that kind of pressure it should be fine. In terms of the relay, you still need to switch it w/ the RPi, so just be sure it can take a low voltage input (~ 3.3V) and switch your pump output.Hope that helps! LMK if you have any further questions.
omg i love this lol
Big Mouth Halloween Face Paint!!!
Heck yes!!! That's so awesome!! :D Love the photo, is that the built in square wave generator?
Oh jeez yea using this with the house main voltage could end up very bad! It would probably be fine as the gnd connection, but shorts would be very dangerous and not worth the risk.Super cool to hear how you've solved the limited Arduino gnd pins in a different way, that sounds like a great approach! I might actually try that -- I've wanting to add an LCD screen to different projects but never seem to have enough pins leftover after adding sensors and such, lol.
Build a Quick, Easy (& Free...View Instructable »
Thanks to a great suggestion from a helpful commenter, I'm thinking of adding a second tutorial on measuring simple circuits w/ the oscilloscope. Regardless, gotta give props to the awesome folks that donated the kit for educational purposes!
Exactly! Yea voltage measurements are iffy but waveform visualization is super useful.
Thanks a ton for the helpful responses, llanE1 and JUANKERR! I would also reiterate that this scope isn't rated for 120 VAC, so if you are new to this type of thing I'd recommend starting with something smaller and safer.
The one that I've linked to in the tutorial is a partially assembled kit -- the ICs and other small components are already assembled, but you have to solder on the through-hole components (resistors, capacitors, connectors, etc.). It takes about 2-3 hours, but is pretty easy and a good practice in soldering and identifying circuit components.
Cool case, thanks for sharing!
APIS - Automated Plant Irrigation System
Essential Backcountry Camping Preparation Checklist
EWaste 60$ 3DPrinter
Leather Plague Doctor Mask
Arduino Tutorial: Capacitive Touch Sensors
Ammo Box Amp
Large Distressed Gear for Steampunk Costumes
How to Make an Individually Addressable LED Matrix Sign
DIY Small Bench Power Supply
USB Microscope Guided PCB Drill
Wooden Rag Doll
Join 2 million + to receive instant DIY inspiration in your inbox.
© 2016 Autodesk, Inc.