Left Sonar Sensor of Quadcopter. Distance affected by wind turbulance.

Hi guys, I have a quadcopter which I have mounted a sonar sensor at the left side of the quadcopter to sense distance. However, the distance measurement is affected by wind turbulance of the propeller of the quadcopter. Anyone know how to reduce the effect of wind turbulance of the propeller of the quadcopter on the measurement of the distance?

I assume the sonar sensor operates at frequencies above human hearing, but perhaps the propeller noise has some frequency components in the range of the sensor's operating frequency. You might want to try an optical method instead.

Hi thx for the reply. What is optical method?

What is optical method?

Shine a light (IR LED) and measure the reflected light (IR Phototransistor). It won't give you a distance but it will allow you to avoid bumping into objects. You will probably want to measure the difference in received light between the LED being off and on. That will allow you to ignore ambient light.

For optical distance measurement you can use an IR distance sensor: http://www.trossenrobotics.com/sharp-ir-distance-sensor-gp2y0a02yk.aspx At $15 each they are much more expensive than a $2 ultrasonic sensor.

You assume that it is the wind turbulence, or you have tested it somehow? Perhaps you are just getting doppler from reflections from the blades. Perhaps you could add "muffs" or acoustic shields to narrow the beam and avoid the blades.

Hi guys!

Anyone have any ideas on how to mount a sonar sensor on a quadcopter so that the sonar sensor reading is not affected by wind turbulent and Acoustic Noise?

Thanks! :slight_smile:

Isn't this just a restart of your previous thread?

Where you never answered to reply #4?

moderator: Topics merged and moved

I suppose it's possible turb

the distance measurement is affected by wind turbulance of the propeller of the quadcopter.

You assume that it is the wind turbulence, or you have tested it somehow?

I agree with aarg, how do you know it's wind turbulence?

What sort of readings were you expecting and what readings do you get?

I did some tests with an ultrasound sensor and a heat gun. I could blow hot or cold air across the path of the sensor without it interfering in the sensor's readings.

I tried adding an ultrasound sensor with a small quadcopter but as soon as the motor were turned on I got very erratic readings from the sensor. I don't think the wind turbulence caused the trouble; I think the motors produced sounds which interfered with the sensor.

I believe it's possible to use ultrasound sensors on quadcopters but I think quadcopters present challenges land based robots don't present.

Where do you want to use the quadcopter? Will this be outdoors? If so your options for optical solutions is limited since most IR distance sensors don't work well in direct sunlight.

There are laser rangefinders which work in direct sunlight. I have a SF02 from Lightware which works great in full sunlight.

Parallax sells several different versions of Laser Rangefinder from Lightware. All them cost much more than an ultrasound sensor. (I received my SF02 as partial payment for writing Propeller software for Parallax.)

There's a less expensive laser rangefinder. SparkFun sells the LIDAR-Lite v2.

I've heard this works great for the price. I'm pretty sure it will work in direct sunlight.

It's possible ultrasound will work for this application, but it sounds like it will require some experimentation to isolate the cause of the trouble you're having.