The following part origins from :   

BUYINGGUIDE

Visual Navigation Settings:

This is where you can control which sensors are on. It is recommended that all the sensors are kept on at all times.

Enable Obstacle Avoidance: With this setting enabled your aircraft will detect obstacles in front of it and it will limit the max speed to 10 m/s so the aircraft has time to break when it detects something. Obstacle avoidance may not work in low light situations (300 lux or below) and it will struggle to detect thin obstacles such as wires.

Enabled Horizontal Obstacle Avoidance in Tapfly: If this is activated your aircraft will fly around obstacles in TapFly mode.

Enable Backward Flying: If this is toggled then the drone will fly backwards when an approaching subject is being tracked. Note, DJI drones with the exception of the Phantom 4 Pro do not have any rear obstacle sensors so it may crash into anything behind it.

Enable Obstacle Avoidance in Active Track: If enabled the aircraft will avoid obstacles in ActiveTrack. If disabled the aircraft will just come to a stop.

Display Radar Chat: If this enabled then the app will display a little radar on the bottom left of the flight view which shows your orientation when flying.

Advanced Sensor Settings:

Enabled Vision Positioning: If this toggled then the downwards sensors will be turned on which will help to keep the aircraft in a fixed position when hovering. When turned off your aircraft will drift when it hovers if the GPS signal is too weak.

Landing Protection: When enabled the aircraft will check its landing area for suitability before it touches down.

Precision Landing: If this is turned on then the aircraft will try to land in the exact spot it took off from when RTH is triggered.

RTH Obstacle Check: If enabled the aircraft will automatically ascend to avoid any obstacle if it detects an obstacle during RTH. For the Spark, if the distance is over 100 meters, then the aircraft won’t avoid an obstacle as it will be travelling too fast.

LEARN MORE

hey, guys
Here is one part from the "DJI Go 4 Manual".
click here if you want to know more about the whole parts. https://forum.dji.com/thread-118397-1-1.html
Enjoy and tell about how this may help and what do you think

Montfrooij Posted at 2017-11-14 23:30
Hey, why is your reply above mine?
It was posted later (your post)?

hahaha, sorry for that. Because I reply for some articles as admin and then top my replies. I will fix it now.

Nice addition

Montfrooij Posted at 2017-11-14 14:58
Nice addition

hahaha, glad to see you leave message here!

DJI Grace Posted at 2017-11-14 18:26
hahaha, glad to see you leave message here!

Hey, why is your reply above mine?
It was posted later (your post)?

DJI Grace Posted at 2017-11-14 23:39
hahaha, sorry for that. Because I reply for some articles as admin and then top my replies. I will fix it now.

Ah. That way.

nicely done - thanks for sharing.