Build a motion detector

[°Bandit°]

motion detector schematic

hi im new here and i was wondering if it would be possible for me to build my own motion detector and if so does any one have instuctions ? :?: ? thanks the bandit :2gunfire:

 

[flatulent]

motion detector schematics

There are three basic methods.

1. Doppler shift of microwave signals.

2. Doppler shift of ultrasonic signals.

3. Infrared sensors with jeweled lenses.

Method two above would be the easiest for beginners. Method three requires specialized lenses which are not available to the public.

 

[djalli]

microwave motion detector schematic

I know another one:

4. Using Hall Effect sensors.

Actually the cheapest (not necessarily the easiest) one used by amateurs and in some commercial entities as mentioned above is method 3.

and the one used by police, military, goverments etc. and other entities which have no problem to spend a little more money are methods 1. and 2.

 

[jayxflash]

build a motion detector

does anybody have WRITTEN INFOS about building such a motion detector ? I've searched almost 200 pages on google and i did not find any schmatic diagram. please share this info if you have it!

thanks!

 

[djalli]

microwave motion detector circuit

Google! Lots of schematics! Lots of explanations!

**broken link removed**

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http://www.glolab.com/pirparts/infrared.html

http://www.earthsands.com/holiday/halloween/propsmotioncontrol.html

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[Borber]

infrared motion detector circuit

I could not find this file on the web so I am uploading. This is ultrasonic motion detector with schematics PCB and building instructions.

 

[djalli]

ultrasonic motion detector project

Out of curiosity you are a begginer in electronics?

If you are serious then buy this book:
https://amzn.to/2tOGRnu

Good luck in your project!
djalli

 

[Hai_Men]

ultrasonic motion detector circuit

If you can't get Borber file, here is the link:

**broken link removed**

have a look

 

[Mike zhang]

motion detector schematic diagram

have a look at this paper.it may help you !good luck

 

[mitesh]

ultrasonic motion detector schematic

Best way is by ultrasonic else use infrar sensor for motion detection

 

[GrandAlf]

build motion detector

Do you want to actually measure the amount and direction of motion, or just detect that it is there. If it is the latter, just use a simple cheap intruder alarm PIR. Otherwise the methods above.

 

[abated_mars]

motion sensor schematic

hey i m working on a similar ciruit for ultrasonic motion detector the circuit in pdf..I am having problem in understanding the first stage of LM324 what eaxtly is happening(u can download thhe ckt from the post above).help me its urgent

Added after 10 minutes:

UltrasonicMotionDetector.pdf is the name of the pdf in the above post

 

[jasmin_123]

microwave motion detector

**broken link removed**

 

[raghu.khanna]

building motion detector

i amplifiers in the "ultrasonicmotion.pdf " file are used to amplify the small mV signal which u receive from the transducer..each stageVwill help in amplification ...BUT how will we detect the motion ??it will be same as receive the ultrasonic waves from the stationary object????

 

[Siniša]

ultrasonic motion detector

This is not doppler shift sensor.
Circuit amplifies reflected signal from objects and rectifies it to get envelope of the signal. As object moves, amplitude changes and second amplifier will amplify those changes in envelope. If those changes are larger than trashold set in hysteresis of 3rd amp and longer then set in LPF of R13,C7 and R14,C8 it will generate pulse of length set by same filter.
So, in a sense, it works very simillar to PIR detector, only uses sound instead of light.

 

[abated_mars]

microwave motion sensor schematic

hello SINISA .
.I am looking for detail explanation about the envelop detector part of the circuit?How is the LM324 -1 is detecting the motion and how is LM324 -3 able to set the threshhold

 

[Siniša]

ultrasonicmotiondetector.pdf.

D1 rectifies signal and C3 filters carrier frequency, so resulting DC amplitude is proportional to reflected signal. If object moves, it will reflect different levels of signal and this DC level will change as well. Those changes are amplified by next AC coupled amplifier and again rectified and filtered by D2,D3 and C6. That DC level is proportional to change of reflected amplitude, ergo movement of detected object. There is no hysteresis in 3rd amp, sorry my bad. There is trashold though, as pairs of resistors R9,R11 and R12,R10 set different voltage levels to keep LM324-C output low. So this amp will work as comparator. Filter after that and pulse extender with LM324-D prevent false detection.