Hello. I want to include a capacitive proximity sensor in my project to help detect plastic/glass objects. However, I'm having a hard time figuring out how I would connect it to my Arduino Uno and if I would need an external power supply/relay/anything. Does anyone have the circuit diagram for it or know how I can find it?
Thanks in advance.
I have a proximity sensor that needs 12v to run. I assume that due to its internal circuit loss it reads 9.9v. its the normaly closed type. here is the issue: i need a voltage divider to drop that down to 5v. that should mean any two equal resistors. yet when i read that voltage, instead of being 4.something i get a read of 0.4v. I cant seem to figure out why this is happening. i have tested with 470ohm resistors, 200ohm resistors, and 16k resistors. those are the ones i have on hand. I have also wired up a 7805 regulator and get the same 0.4 read from it..... my meter reads 5v correctly when i measure my 5v supply for the octopi. what gives?
My sensor is ljc18a3-h-z/bx. It measures 9.8v when nothing is detected. and when it lights up it measures no volts.
Edit: Here is an idea. I have an adjustable buck converter on hand. I am going to see how it behaves if i feed it 8v or something.
Edit2: If i dial the input down to 7v, i get 5v on the signal line. However that brings the detection distance down to the point where its almost even with the nozzle. Tinkering shall continue.
Final Edit: I am changing course, and just ordered an IR sensor from Filastruder. Its 5v natively, so the whole voltage issue just dissapears. Thanks for all your input.
So I know that there's industrial capacitive sensors capable of measuring non-conductive material thickness including ones that work from just one side (!!!). I'm wondering if you can do the same thing with these cheap foil sensors and an arduino, and what kind of range and accuracy I could expect from such a project.
I'd like to measure a non-conductive material with a max thickness of several inches. I can have plates on both sides if needed. Thoughts on if this is possible?
Hello guys.
I have a problem and it's driving me nuts. A LED lighting strip in my kitchen is controlled by a capacitive touch switch that is glued on the inside of a cupboard so when I touch it on the outside the lights turn on.
But - this is somewhat above the induction hob and thus fairly close to one's head when cooking (some 30 cm) and whenever the person comes into conductive contact with the pan/pot/whatever on the active induction hob, due to some EM antenna/interference phenomena, the switch detects it despite any part of the body being far from its normal range (usually about 1 cm from the cupboard wall).
I did a few "measurements" and there is a sizable "sphere of influence" about 40 cm in which if any part of one's body is at the moment the person comes in contact with a pot on the stove, the switch detects it.
As you can imagine, cooking with lights coming on/off constantly sucks.
Is there anything that can be done to prevent this? I was experimenting with glueing pieces of various materials between the switch and the cupboard wall to reduce the sensitivity, but nothing seems to do the trick.
Ideas will be greatly appreciated.
edit - worst case scenario, we place the switch elsewhere, but we kind of like this placement and it also became somewhat of a challenge to crack.
So, I'm trying to detect a cup of water through a sheet of lexan. I want the sensor to be maybe 3 or 4 cm beneath the sheet. What type of sensor should I use?
I heard Quantec used to have the QT130 which was replaced by the QT100A, but I can't find that in DIP. I don't know what else to search for.
Oh, and I'm using an Arduino if anybody was wondering.
Edit: I guess 3cm is quite a distance for this sort of thing. I suppose I'll just have to go right up against the surface.
So I added a capacitance sensor to my ender 3 to help with the warped bed. It works great for anything not on the edge but the sensor is not getting to the edge of the bed on the left or right. Obviously the right will be off as it is mounted to the left but it could certainly travel a bit further. Does anyone know how to tune this value, or have a value that they could share assume this could be a one size fits all type of thing.
Edit should state am using Marlin 1.1.x
Hi!
Having some problems, in particular with Into The Radius VR, where my hands get pretty sweaty and that messes up the "grabbing" part of the game.
I couldn't find any decent guide on how to rebind grabbing to be executed with force, instead of the capacitive sensors.
What I've tried:
Rebound controller mapping for ITR, section "Grip" to "USE AS FORCE SENSOR" -> Force -> Left/Right Grip Value.
Upon testing it in game, it seemed that it wasn't controlled by force in any way, while still using the capacitive sensors.
Am I missing something here, or is there another way?
The analog stick on my left controller no longer senses touch. The sensors on the touch pad, buttons, and edge still work. My guess is the tiny ribbon cable that runs up through the stick is worn and damaged. Before I try to RMA it, I thought I would see if there are any known causes of this other than a broken cable and if there are any known fixes. Would rather not go through the RMA process and probably won't even do it unless Valve does an advanced replacement. Just not worth going several weeks without the controller.
I'm trying to build a fringe-field capacitive sensor to measure liquid level in some tanks with varying thicknesses / materials. I would appreciate any advice and resources (textbooks, papers) on how to build the electrodes, where to buy any pre-made ones (interdigitated / circular electrodes), how to shield them properly, etc. Also I would appreciate any readings/textbooks to learn more from, like how to calculate fringe field depth and strength depending on the thickness and content of different materials
I'm working on a project and the latest fingerprint sensor I got was the dfrobot one, but it is very slow, I want one that is much faster, no idea were to look hopefully one of you can help me
I'm trying to build an energy-efficient soil moisture measuring system. I am using an ESP32 and 3 "Capacitive Soil Moisture Sensor v1.2" connected to an ADS1115. The sensors don't have a power off function, so I'm using a p-channel MOSFET to switch them off when they aren't measuring. (https://i.ibb.co/QrxTbFt/circuit.png)
This works pretty well for energy-efficiency, but the accuracy seems to suffer. When not switching the sensor off I get pretty much the same measurement result every single time. When switching, the measurements go up and down by about 3 percent points. This issue is caused because the supply voltage for the sensors is not always exactly the same when switching.
To combat this, I installed a ceramic 100nF and an electrolyt 1000uF capacitor on the supply for the sensors. This stabilized the supply voltage and massively reduced the inacurracies but created a new problem. Under some circumstances I don't fully understand I get a brownout shutdown by the ESP32. (https://i.ibb.co/WxV9Tg0/index.jpg)
Do you know what could cause the brownout and how to prevent it? Or can you reccomend another way of solving the problem with the inaccuracy?
I recently ordered a bunch of capacitive soil moisture sensors for a plant care project. During testing, I noticed that unfortunately some of them were very unresponsive and responded extremely slowly to changes in soil moisture.
It turned out that the reason for this is that a 1MOhm resistor is not connected to ground because a misplaced via hole is interrupting the copper path on the circuit board. I scratched off the silk screen to make the problem visible.
Faulty sensor with interrupted copper path
What its supposed to look like
It can be fixed by soldering a new 1MOhm resistor between the analog-out pin and the ground pin of the sensor or by soldering a cable between the ground pin and the disconnected side of the existing resistor.
I just wanted to let you know in case you have any problems with your sensor readings too.
In case you are currently about to buy such a sensor, look carefully at the product pictures and make sure the via hole is placed correctly. Also make sure it has a voltage regulator and a suitable timer chip on board, otherwise there could be other problems. More on that here: https://www.youtube.com/watch?v=IGP38bz-K48
Good Morning Everyone,
I've posted a bit here with some of my "hobby farm" style projects. You may have seen my CoopCommand automated chicken coop project or maybe some of my ZoneCommand irrigation stuff. This ties into the latter.
I had previously posted an earlier design of a capacitive soil sensor I had whipped up based on all the commercial designs you see out there and now I'm ready to make a new revision with some tweaks based on field experience.
Basically, at its heart, this is a 555 timer setup to generate a square wave output which is then pushed through a soil probe and the resulting capitance changes can be read through an ADC as a voltage change. Earlier design is here:
https://imgur.com/gallery/eeyLpNt
Now, I am wondering why all the capacitive sensors go to a single probe design when the resistive sensors use a "forked" probe design. I have been re-designing the pcb to utilize a similar probe style as the resistive sensors, but still using capacitive measurement. In my mind the fork design is better for soil measurement with the capacitive sensors as well seeing as the sensor is essentially using the soil as a capacitor, the more soil you have in between the probes, the more accurate/representative the measurement. Am I missing something in my thinking here? Is it just to keep costs down as you can panelize a single probe design in a more compact manner?
Here is my current updated design, the circuit itself seems to function similar to the purchased versions although I find mine reacts faster to changes in moisture levels faster than the store bought ones.
https://imgur.com/gallery/qLiXSSw
So I guess my main question for this sub is: Does anyone see a reason why not to separate the probes in two different forks to ensure they have soil between them?
I have a lamp with a Cree zigbee light in it. I'd like to be able to touch the lamp and have a capacitive sensor tell my system to change the lamp's brightness and/or turn the lamp off. So I think basically all I need is for the sensor to send a 'triggered' message to my HA system via wifi, zwave, or zigbee. Then I can automate using that trigger to cycle through off/on, and five levels of brightness. I have not found any 'smart' capacitive sensors except wall-mounted switches, and I want to be able to just touch the bedside lamp.
