91–100 of 108 posts
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Is the LD2410B sensing range limited by the PCB antenna?
I'm not sure, it always just made sense to me that the farther away someone is, the harder it'll be to detect their small movements.
Detection range without obstacles depends on transmit power and signal reception.
There are other models in the same family which might have more power/range.
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If your fine with zigbee, I could see having one of these aqara door sensors in the cushion of the seat, triggering to closed when you sit on it: https://cloudfree.shop/product/aqara-door-and-window-sensors... Seems like it'd be finicky though.
Zigbee is great, but my chair has a mesh :/ I'll see if I can print something below, so that the sensor is activated, but yes, it does seem that it would be pretty finicky...
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Zigbee is great, but my chair has a mesh :/ I'll see if I can print something below, so that the sensor is activated, but yes, it does seem that it would be pretty finicky...
Ceiling sensor is another option.
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If your fine with zigbee, I could see having one of these aqara door sensors in the cushion of the seat, triggering to closed when you sit on it: https://cloudfree.shop/product/aqara-door-and-window-sensors... Seems like it'd be finicky though.
Zigbee is great, but my chair has a mesh :/ I'll see if I can print something below, so that the sensor is activated, but yes, it does seem that it would be pretty finicky...
You cannot try to rationalize the prices that China charges for goods. Everything is, more or less, state-owned and state-controlled. If the Chinese government wants to undercut an American product, they will tell the manufacturer to drop the price to X, and the manufacturer will comply. This also does not take into account Chinese currency manipulation. Profit or loss be damned.
Isn't the US basically the same? The US government gives massive subsidies, tax breaks or just has the military buy components for 10x the price (to offset commercial loses and R&D).
None of this is really true of the Chinese system.
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I need to see a picture, but fyi some of components of an antenna are "electrically" disconnected, but still play a role, wave guides being one example. Also note, if you are just receiving signals you have more freedom to experiment. Antenna tuning matters a lot more when transmitting (especially at larger powers). (Not implying that it doesn't matter with reception)
Just to clarify - I changed transmitters antenna.
Sounds like you might have inadvertently created a wave guide.
If you are feeling adventurous you might want to try dropping your creation into an Antenna Simulation software like NEC or something similar.
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Wrong, most of these radars are 24Ghz and specifically designed to detect body micro movements. They specifically give both human 'occupancy' and dynamic ranging information. I wrote low level drivers for the ESP32 for all the ones I could buy and have tested all of them. The only one that does not try to give a human occupancy position is the car speed sensor. The ld2450 can track three people at once. https://githu…
This sounds very interesting, how do your drivers work? I'd love to try them out, but there's no documentation. I've made a sensor board with various sensors, I could really use some occupancy detection improvements on the LD2450B.
Almost not related, but reminded me about recent RC hack I was working on. I have an driveway alarm from mighty mule, which uses 433Mhz radio powered by two AA batteries to communicate signal from the coil sensor detection sitting next to the driveway to the base station in the house using OOK modulation. The stock PCB antenna was not very good at the distance I had it to work with, so I started experimenting with ex…
I have had decent success with them when finetuning antennas for lower bands.
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This sounds very interesting, how do your drivers work? I'd love to try them out, but there's no documentation. I've made a sensor board with various sensors, I could really use some occupancy detection improvements on the LD2450B.
here is the ld2450 multi object tracker: https://github.com/mianos/mqttradar It's pretty complete. There was some other guy who wanted an ld2450 tracker so I worked with him to get it going.