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4

This will not work if you stand on it. Ultrasonic sensors have a minimum distance from which they can accept reflections, because the transducers themselves ring, so the circuit has to blank any reflections received while ringing is expected. Even with distinct transmitters and receivers, there's enough electrical and/or acoustical coupling between them ...


3

This sounds like you're trying to build a boogie dance floor and sense when a person is on each tile. As others have said, the ultrasonic solution is unlikely to work well for you. Options: A force sensor in each corner or the middle or some combination of corners. Strips of safety or intruder mat around the edges supporting the frame. Rest the corners on ...


3

It is possible to measure distance with a single ultrasonic transducer. First the the transducer is used to transmit an ultrasonic pulse, and then the same transducer is used to receive the echo thrown back from the objects in front of it. The disadvantage of using a single transducer is, that it is very difficult (impossible) to detect objects that are ...


2

No, those sensors use a TTL level output signal for echo, so you'll have use an or gate or diodes plus a resistor to implement an or gate. You can drive all the triggers with a single output, although you won't be able to tell which sensor each echo comes from and multiple echo pulses that overlap will appear as a single long pulse. simulate this circuit &...


2

Solved! servo.h library messes up with the Arduino pwm pins. It disables the 9,10 pins even we haven't connected a servo to that. That is the issue here. Have to use pwm other than (9,10) for the motor driver's enable pin.


1

If the time is longer than 0.04 then it means that the Pi "missed" the return because it wasn't fast enough to see the rapid return. It's basically a sanity check because after 0.04s it would mean the return pulse was missed or the object is physically out of range of the sensor.


1

Use a P-channel MOSFET eg. AO3401A to cut Vcc. Low to the gate = ON. simulate this circuit – Schematic created using CircuitLab Add a 1K resistor series with the TRIG input and make sure that you drive TRIG low before shutting off the Vcc and do not drive it high until after Vcc has been turned on. Also do not drive ECHO high as an output (it should ...


1

what passive components could be used in place of the removed transducer? The dominant equivalent component is a capacitor. The value varies from transducer to transducer. A measurement of one example was 1.3 nanofarads. Since the circuit is unknown, it is impossible to say if a transducer should be replaced with an electrical equivalent...no replacement ...


1

It's not impossible. See http://www.buildcircuit.com/how-to-test-dyp-me007-ultrasonic-range-finder-using-ne555-and-multimeter/ But it won't work like you want without a needlessly complex circuit. The HC-SR04 or similar ultrasonic range finders have a fairly small output timing, that tells you how far something is. If nothing is near, the output is high for ...


1

The Echo pin is a TTL output1, according to the datasheet for the HC-SR04. Don't wire the Echo outputs together directly. If one output is in a high state and another output is in a low state and they are connected together, then one of the outputs can burn. Instead, combine the outputs using an OR gate IC. 1 If it were open-collector or an open-drain ...


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