about ultrasonic module JSN-SR04T

[AliBahar]

Hi
it is claimed that the max range of measuring of ultrasonic module JSN-SR04T is 5m.
I have applied the 10 us high level signal to Trig pin but always the max high time of echo is less than 10ms. so the max range which I can detect with this device is near to 1.6m. by the way the high time of echo is measured by digital Oscilloscope.
has anyone gotten the better prformance from this device?
is there any point which i forget.

 

[paulfjujo]

hello

Mesure OK de 30mm à plus de 3900mm!!!
it is same device as**broken link removed**

 

[milan.rajik]

Yes, I have used that sensor. It measures upto 200 cm (2 meters). I have successfully used it to measure more than 2 meters. I also use US020 similar sensor which can measure upto 7 meters. I was successful in using both precisely.

 

[FvM]

I see two versions of the sensor.





For both, I would expect 5 m range only under optimal conditions, e.g. large and acoustically hard target perpendicular to the sensor axis. It's using a typical car obstacle detection transducer, mostly operating in a range up to 1 or 2 m.

 

[paulfjujo]

hello

I have applied the 10 us high level signal to Trig pin but always the max high time of echo is less than 10ms. so the max range which I can detect with this device is near to 1.6m. by the way the high time of echo is measured by digital Oscilloscope.

By the way, how do you measure the echo ..
is it the time between Trigger and front edge .. or back edge Echo signal...
on HC SR04 echo time is on back edge .. so include all duration of the echo at logical status ONE.

 

[AliBahar]

By the way, how do you measure the echo ..

in the module's user guide it says that the time duration of high level echo is the duration of time of flight.
when the 10us pulse receives to trig pin the echo goes high and when the reflected wave receives to echo pin it goes down.
so i have calculted the time between generating 10us and falling edge of echo

 

[paulfjujo]

hello,

so i have calculted the time between generating 10us and falling edge of echo

so,it is correct...
did you notice the angle value of ultrasonic .. < 50°
but 15° only on HC-SR04 model wich has One emitter and one receiver.

So it means that you must have a quite big area target in front , to detect it far from the emitter.

 

[AliBahar]

So it means that you must have a quite big area target in front , to detect it far from the emitter.

that's right. the cross section of obstacle must be flat and large enough.