Obstacle avoidance

[Steveo116]

I bought my P4 refurbished and the front sensors work but I dont think the bottom works. If i use the controller to land, it will not stop or avoid objects below. Does the bottom sensors only work for RTH or a bad refurbished?

 

[msinger]

The bottom sensors are not used to avoid obstacles. That's working as designed.

 

[Steveo116]

The bottom sensors are not used to avoid obstacles. That's working as designed.

Thanks, I thought I a bad unit.

 

[wa5tef]

Bottom sensors? What are they used for? I have used the front sensor several times but not the bottom ones.
Thanks,
Jim
WA5TEF

 

[Deleted member 62848]

Bottom sensors? What are they used for? I have used the front sensor several times but not the bottom ones.
Thanks,
Jim
WA5TEF

Bott is vps front obstical advoidsorry vps is vision positioning system

 

[Steveo116]

Bottom sensors? What are they used for? I have used the front sensor several times but not the bottom ones.
Thanks,
Jim
WA5TEF

I heard the phantom 4 had 2 different sensors, one forward and one downward. I guess the downward sensor is for better stability.

 

[Deleted member 62848]

I bought my P4 refurbished and the frint sensors worj but I dont think the bottom works. If i use the controller to land, it will not stop or avoid objects below. Does the bottom sensors only work for RTH or a bad refurbished?

bit of info

 

[dwallersv]

The P4 has 4 downward-facing sensors: 2 cameras and 2 ultrasonic ranging sensors.

The cameras are used for positioning -- keeping the bird over the same place on the ground. GPS alone is not accurate enough.

The ultrasonic sensors provide altitude data below 10 (or is it 15?) meters. This provides millimeter precision, far more accurate than the barometric altimeter (and GPS-derived altitude).

Both Visual Positioning and the ultrasonic sensors can be fooled/defeated by certain incompatible surfaces. In some of these situations VPS may need to be disabled to keep the drone from flying erratically.

 

[wa5tef]

Yeah, I remember reading about that but had forgot it. So the drone should have accurate altitude readings using these systems rather than relying on GPS? My Phantom 4's altitude is off by 10 to 15 feet on most every flight. I am afraid to fly it as low as I would like to because of this. I believe several more have posted about having this same problem with altitude readout. I've tried it in DJI GO and Litchi with the same error.
Thanks,
Jim
WA5TEF

 

[Deleted member 62848]

Yeah, I remember reading about that but had forgot it. So the drone should have accurate altitude readings using these systems rather than relying on GPS? My Phantom 4's altitude is off by 10 to 15 feet on most every flight. I am afraid to fly it as low as I would like to because of this. I believe several more have posted about having this same problem with altitude readout. I've tried it in DJI GO and Litchi with the same error.
Thanks,
Jim
WA5TEF

Hi i never checked that with mine and some fast flights are half metre above the ground,got BIG flat feilds here,,i be a bit cautious now