Hi all , I want to control a linear actuator by moving my hand in front of a piece of 12mm lexan . Lexan is similar to plexiglas , and I want the sensor hidden behind it .
Any recommendations would be greatly appreciated
What kind of control exactly?
LIDAR should work. I had a project where I had a LIDAR unit inside a 1/4” thick clear PVC tube. Worked great. Think i used a Sparkfun Lidar Lite.
Microwave sensor like RCWL‑0516 can easily detect through 12mm polycarbonate, but you need to place it in metal enclosure open only to your "gesture zone". And it cant make a difference between hand wave and walking person.
Something like this could work as well:
https://aliexpress.com/item/1005009057811221.html
First, figure out if you can use a radar sensor to control the actuator, then worry about the lexan, as that is the least of your problems.
1 Like
Let’s be sure what we are taking about. Is there any color in your lexan and is it powered metal?
Hey all sorry for being to vague. I’m going to be using 12mm thick clear Lexan , but I did want to paint the underside of the Lexan with white latex paint .
I don’t know if that’s an be issue , but seeing as I want to use radar , basically a microwave sensor , I don’t see why it wouldn’t work .
My concern is I will be adjusting a subwoofer gain control that will be close to the radar sensor , say 6 inches above it . This is in my home gym btw ,not car audio .
I have built an iPad stand that extends out via actuators . The iPad is secured to a magnetic plate so that I can remove the iPad if I want to .
I thought it would be really cool to be able to do something other than use a mechanical switch to make it extend out and in . As I’m posting this it’s on a wireless remote .
Also I’m not sure if you can change the sensitivity of the radar sensor and make the distance it works fairly short in order to prevent false movements if I’m standing 18-24 inches away ?
I don’t know if we can post YouTube videos here but I’ll try .
Guys that empty space where you see that subwoofer knob above the iPad is where the lexan is being mounted .
I wanted the sensor to be approx 6” above the knob hidden behind the lexan
No, there is no sensitivity adjustment because it depends on the time between sending the radar pulse and the echo being received. Sensitivity is irrelevant.
Your code determines what is to be done with the distances computed based on the echo time. So, you are in complete control of what is done with distances being sensed/computed.
I am guessing you have not done any testing or reading of the documentation. Start now!
This would be a great time to get one or more radar sensors compatible with Arduino and learn how they work.
The readily available radar modules are generally designed to detect objects up to about 100 m away, and are intended for example for automobile collision avoidance or to warn bicycle riders of automobiles approaching from the rear.
Consider instead this IR gesture sensor, which is great for analyzing hand motions at close range. It may not work through lexan, though.
Especially painted Lexan!
A clever person might drill a small hole for the sensor openings ;)
lol I have thought about that . I was after stealth though
while I don't have 12mm lexan, the LD2420 works through 1/2" (12.5mm) glass.
LD2420 has configurable distance range (6 zones if I remember well) and configurable sensitivity.
It does not support gestures but you can play with the distance it reads and figure out a simple motion direction algorithm.
The reading angle is 60° which on the lowest distance setting (0-70cm) should be quite narrow.
There are other radar devices than can read gestures that I haven't any experience with.
edit: LD2420/examples/AdvancedUsage/AdvancedUsage.ino at main · cyrixninja/LD2420 · GitHub