DJI Mavic, Air and Mini Drones
Friendly, Helpful & Knowledgeable Community
Join Us Now

Don't use or rely on fail-safe system as part of normal operation

RayOZ

Well-Known Member
Joined
Nov 16, 2017
Messages
1,497
Reactions
1,531
Location
Brisbane, Australia
As drones gets more and more advance, there'll be more intelligent built-in fail-safe system to prevent crashes and loss of drone. But it should be part of normal usage. And don't be complacent about it.
As a control systems engineer, I thought I explain my point of view.
There are usually 2 level of alarms, the first is to let the operator know a system is operating outside normal safety parameters. The second alarm is more critical, and the control system takes over to prevent failure, in the event the operator fails to address the first alarm. For example, a system monitoring a high pressure tank. The first high alarm lets the operator know that something might be wrong, and should look into bring the pressure down the below the high level. If the second high high alarm is triggered, the control system takes over, either opening relief valve or shuts the system down to prevent a catastrophe. The control system assumes the operator has fallen asleep on the wheel or has no idea what to do. The system was meant to operate below the high level alarm. Many an engineering disaster occurs when operators think the system can run between the high and high high level, relying on the fail-safe to prevent a disaster. But when the fail-safe fails, we have a problem. Programming how something should operated normally is easy. Making something foolproof, predicting the millions of ways how a human can break a system is almost impossible. As far as technology goes, Artificial Intelligence is still no match for Natural Stupidity.

Back to our drones. Our Mavics have fail-safes, like the fail-safe RTH in the event of loss of connection to the RC. When there's a weak connection between AC and RC, there's a warning on the DJI Go 4 app. It's to let the pilot know to do something about it, as in, to improve connection. Not keep flying until loss of connection and just wait to RTH to kick in. And if that happens, when connection is re-establish, it doesn't mean you stop the RTH, turn your drone around and try again with whatever you were trying to do the first time. You are just pushing your luck, and eventually, it might run out. Not only would you have lost of visuals and control of the drone when the RC and AC disconnects, you've also lost telemetry in the flight logs. So, if the fail-safe fails, you might have difficulty finding your drone, and even if you do, the likelihood of finding it intact without a scratch is very slim.

Our drones are an expensive investment, not a $1000 boomerang you throw and assumes it'll always come back.
 
As drones gets more and more advance, there'll be more intelligent built-in fail-safe system to prevent crashes and loss of drone. But it should be part of normal usage. And don't be complacent about it.
As a control systems engineer, I thought I explain my point of view.
There are usually 2 level of alarms, the first is to let the operator know a system is operating outside normal safety parameters. The second alarm is more critical, and the control system takes over to prevent failure, in the event the operator fails to address the first alarm. For example, a system monitoring a high pressure tank. The first high alarm lets the operator know that something might be wrong, and should look into bring the pressure down the below the high level. If the second high high alarm is triggered, the control system takes over, either opening relief valve or shuts the system down to prevent a catastrophe. The control system assumes the operator has fallen asleep on the wheel or has no idea what to do. The system was meant to operate below the high level alarm. Many an engineering disaster occurs when operators think the system can run between the high and high high level, relying on the fail-safe to prevent a disaster. But when the fail-safe fails, we have a problem. Programming how something should operated normally is easy. Making something foolproof, predicting the millions of ways how a human can break a system is almost impossible. As far as technology goes, Artificial Intelligence is still no match for Natural Stupidity.

Back to our drones. Our Mavics have fail-safes, like the fail-safe RTH in the event of loss of connection to the RC. When there's a weak connection between AC and RC, there's a warning on the DJI Go 4 app. It's to let the pilot know to do something about it, as in, to improve connection. Not keep flying until loss of connection and just wait to RTH to kick in. And if that happens, when connection is re-establish, it doesn't mean you stop the RTH, turn your drone around and try again with whatever you were trying to do the first time. You are just pushing your luck, and eventually, it might run out. Not only would you have lost of visuals and control of the drone when the RC and AC disconnects, you've also lost telemetry in the flight logs. So, if the fail-safe fails, you might have difficulty finding your drone, and even if you do, the likelihood of finding it intact without a scratch is very slim.

Our drones are an expensive investment, not a $1000 boomerang you throw and assumes it'll always come back.
could not agree with you more i have always advocated learning to fly your UAV manually, the features are very good but as you say not foolproof,the sensors can be fooled and thats when you need to be able to know how to respond,and fly out of trouble.
 
As drones gets more and more advance, there'll be more intelligent built-in fail-safe system to prevent crashes and loss of drone. But it should be part of normal usage. And don't be complacent about it.
As a control systems engineer, I thought I explain my point of view.
There are usually 2 level of alarms, the first is to let the operator know a system is operating outside normal safety parameters. The second alarm is more critical, and the control system takes over to prevent failure, in the event the operator fails to address the first alarm. For example, a system monitoring a high pressure tank. The first high alarm lets the operator know that something might be wrong, and should look into bring the pressure down the below the high level. If the second high high alarm is triggered, the control system takes over, either opening relief valve or shuts the system down to prevent a catastrophe. The control system assumes the operator has fallen asleep on the wheel or has no idea what to do. The system was meant to operate below the high level alarm. Many an engineering disaster occurs when operators think the system can run between the high and high high level, relying on the fail-safe to prevent a disaster. But when the fail-safe fails, we have a problem. Programming how something should operated normally is easy. Making something foolproof, predicting the millions of ways how a human can break a system is almost impossible. As far as technology goes, Artificial Intelligence is still no match for Natural Stupidity.

Back to our drones. Our Mavics have fail-safes, like the fail-safe RTH in the event of loss of connection to the RC. When there's a weak connection between AC and RC, there's a warning on the DJI Go 4 app. It's to let the pilot know to do something about it, as in, to improve connection. Not keep flying until loss of connection and just wait to RTH to kick in. And if that happens, when connection is re-establish, it doesn't mean you stop the RTH, turn your drone around and try again with whatever you were trying to do the first time. You are just pushing your luck, and eventually, it might run out. Not only would you have lost of visuals and control of the drone when the RC and AC disconnects, you've also lost telemetry in the flight logs. So, if the fail-safe fails, you might have difficulty finding your drone, and even if you do, the likelihood of finding it intact without a scratch is very slim.

Our drones are an expensive investment, not a $1000 boomerang you throw and assumes it'll always come back.
Well said and I could not possibly agree more! Too many people use the fail safe modes as their normal way of flying. RTH is nice, but I don't use it as my routine way of getting home. Learning how to navigate manually should be the fail safe for when something goes wrong. Trying to fly your drone in ATTI mode at the edge of controller range is the wrong time for your first exposure to it.
As you mentioned, keep an eye on signal strength and don't wait till you lose signal completely. I will add a few more though. Monitor your battery level and don't wait for the drone to tell you it's low. I always try to be on the ground with 30% left. Never take off with less than a completely charged battery and a good GPS lock.
DJI Care Refresh is great as a safety net, but it is making drone owners complacent. The mindset becomes "I don't need to be super careful because I have two replacements left". Yes accidents can and do happen. However the issue is that many drone owners are ill prepared to handle the tough situations when they arise, because they depend too much on the fail safe technologies.
 
My sister has been an HPDE (High Performance Driving Event) instructor for about 15 years. Her "pet peeve" is those students showing up at events in their new, exotic and expensive sports cars with the attitude that they think they already know a lot about high performance driving. In reality, these students THINK they know a lot when, in fact, it is the "built in nannies" that are actually doing the driving. Same problem exists with these students as with some new drone fliers. When their exotic car does break the "envelope" of control, they have no clue what to do.
 
In about 5 years, there’ll be a next gen of drivers who won’t know how to park their car. They’ll drive up to a parking spot and press the auto park button. In the meantime, they’ll whip out their phone, take a selfie to post on Instagram to announce to the world they’ve arrived.
 
  • Like
Reactions: ForceMajeure
Couldn't agree more. I always land manually. A couple years ago I decided to test the accuracy of RTH on my P3P. I took out to a field near my sister in law and flew it out a couple of hundred feet the pressed the RTH. I did this five times and found that it landed up to 18 feet from the take off point. Where I live there are trees, bushes, houses, cars, fences and most importantly children.

While the Mavic is MUCH better at landing within inches of the take off point, it cannot account for the kids running around. They see a drone and they just have to take a closer look. While obstacle avoidance may see the child running at it from the front and back off it doesn't know what it is backing into.

At least if I'm landing it I can take it back up until the kids back off.
 
  • Like
Reactions: old man mavic
In about 5 years, there’ll be a next gen of drivers who won’t know how to park their car. They’ll drive up to a parking spot and press the auto park button. In the meantime, they’ll whip out their phone, take a selfie to post on Instagram to announce to the world they’ve arrived.

Sounds like my wife, she couldn't parallel park to save her life. I've parked dump trucks in places she has trouble with. I'd love to see her park a dump with a lowboy trailer.
 
  • Haha
Reactions: BrucenYvette
Couldn't agree more. I always land manually. A couple years ago I decided to test the accuracy of RTH on my P3P. I took out to a field near my sister in law and flew it out a couple of hundred feet the pressed the RTH. I did this five times and found that it landed up to 18 feet from the take off point. Where I live there are trees, bushes, houses, cars, fences and most importantly children.

While the Mavic is MUCH better at landing within inches of the take off point, it cannot account for the kids running around. They see a drone and they just have to take a closer look. While obstacle avoidance may see the child running at it from the front and back off it doesn't know what it is backing into.

At least if I'm landing it I can take it back up until the kids back off.
All true.
Note that by tapping the red “X” on screen left an automated landing it can be aborted. Also note that all control stick directions to the drone are still functional during an RTH, so you can still maneuver and adjust safely.
 
In about 5 years, there’ll be a next gen of drivers who won’t know how to park their car. They’ll drive up to a parking spot and press the auto park button. In the meantime, they’ll whip out their phone, take a selfie to post on Instagram to announce to the world they’ve arrived.

ROFLMBO!! 5 years???? Today's new drivers don't even know what "parallel park" means, much less how to do it LOL! I'll have ask my HPDE-sister if she teaches "parking-without-a-nanny" to her newbie Ferrari drivers who show up wanting to learn how to drive maniacally safe.

Hey, about time someone reminds us that this is a DRONE forum???
 
Sounds like my wife, she couldn't parallel park to save her life. I've parked dump trucks in places she has trouble with. I'd love to see her park a dump with a lowboy trailer.

Better be careful...your wife may park YOU in the dump and go out and find herself a new lowboy LOL!
 
I decided to test the accuracy of RTH on my P3P. I took out to a field near my sister in law and flew it out a couple of hundred feet the pressed the RTH.
I did this five times and found that it landed up to 18 feet from the take off point.
That's not the Mavic you were testing.
It's the variable inaccuracy of GPS.
 

DJI Drone Deals

New Threads

Forum statistics

Threads
132,103
Messages
1,569,651
Members
160,869
Latest member
palaiouras