Litchi Settings Error = Near Calamity

[Billie Nelson]

Having run many successful long range Litchi missions lasting until the battery drains down to 30% over 20 minutes on average, I became complacent, and paid less attention to detail, such as that all-important "Settings" option that MUST be set to have the drone do "Nothing", and NOT do an RTH landing on arrival at the launch point.

With growing confidence in the estimated flight time calculated for each mission by the Litchi Mission Hub, I had developed a habit of noting the takeoff time, adding to that the estimated flight duration, and then going indoors, with the intention of stepping outside exactly 5 minutes before the drone's estimated time of arrival, to disengage the autopilot and manually land the craft. Now this routine had worked perfectly for well over twenty long-range autonomous flights, only for me to get a rude awakening today.

I was sitting indoors at my desktop computer with an eye on the clock, when suddenly, TEN minutes before the drone's expected time of arrival, I heard what sounded like a lawn mower running over a patch of gravel, and then in the same instant, realized that my drone had made a full RTH , and inexplicably scuttled underneath a car parked near my landing pad.

I killed the engines on the remote as I sprinted outside, but those props did impact the floor of the car, and the ground. To describe my mood as dismayed, would be an understatement. I had just affixed a brand new set of props this morning, and already, two of them look as though I tried to mow the lawn with the drone.

After observing the requisite few moments of hair-pulling and rabid teeth-gnashing, I set the drone on my takeoff table, and punched the throttle. The bird lifted up into a dead stable hover, with no immediate indication of any lasting damage resulting from my act of monumental idiocy. None of the props are cracked, but any motor damage that may have been incurred probably won't become apparent until I run a proper test flight within visual range, tomorrow, when I recover from the shock of this debacle.

Moral of story, ALWAYS set your drone to do "Nothing" on arrival at the final waypoint. I was warned about this setting just two days ago in this forum, yet once again, I overlooked that setting, and launched the drone, confident that since all my altitudes had been meticulously cross-checked, nothing could possibly go wrong. Henceforth, I will also remain outdoors for the entire duration of every future flight, and will NEVER rely on the flight time figures from the Litchi Mission Hub since they are after all, subject to wind variations aloft. Wow ! What a day.

 

[bsartist]

Having run many successful long range Litchi missions lasting until the battery drains down to 30% over 20 minutes on average, I became complacent, and paid less attention to detail, such as that all-important "Settings" option that MUST be set to have the drone do "Nothing", and NOT do an RTH landing on arrival at the launch point.

With growing confidence in the estimated flight time calculated for each mission by the Litchi Mission Hub, I had developed a habit of noting the takeoff time, adding to that the estimated flight duration, and then going indoors, with the intention of stepping outside exactly 5 minutes before the drone's estimated time of arrival, to disengage the autopilot and manually land the craft. Now this routine had worked perfectly for well over twenty long-range autonomous flights, only for me to get a rude awakening today.

I was sitting indoors at my desktop computer with an eye on the clock, when suddenly, TEN minutes before the drone's expected time of arrival, I heard what sounded like a lawn mower running over a patch of gravel, and then in the same instant, realized that my drone had made a full RTH , and inexplicably scuttled underneath a car parked near my landing pad.

I killed the engines on the remote as I sprinted outside, but those props did impact the floor of the car, and the ground. To describe my mood as dismayed, would be an understatement. I had just affixed a brand new set of props this morning, and already, two of them look as though I tried to mow the lawn with the drone.

After observing the requisite few moments of hair-pulling and rabid teeth-gnashing, I set the drone on my takeoff table, and punched the throttle. The bird lifted up into a dead stable hover, with no immediate indication of any lasting damage resulting from my act of monumental idiocy. None of the props are cracked, but any motor damage that may have been incurred probably won't become apparent until I run a proper test flight within visual range, tomorrow, when I recover from the shock of this debacle.

Moral of story, ALWAYS set your drone to do "Nothing" on arrival at the final waypoint. I was warned about this setting just two days ago in this forum, yet once again, I overlooked that setting, and launched the drone, confident that since all my altitudes had been meticulously cross-checked, nothing could possibly go wrong. Henceforth, I will also remain outdoors for the entire duration of every future flight, and will NEVER rely on the flight time figures from the Litchi Mission Hub since they are after all, subject to wind variations aloft. Wow ! What a day.

I use “go back to waypoint 1.”

 

[LarBear360]

My first mission went fine until it was about to land when suddenly it made a hairpin turn and went off in another direction. Fortunately I remembered how to cancel the mission and re-take control. Never did figure it out.

 

[bsartist]

My first mission went fine until it was about to land when suddenly it made a hairpin turn and went off in another direction. Fortunately I remembered how to cancel the mission and re-take control. Never did figure it out.

Stuff like this sometimes happen when you are editing a mission and accidentally touch the screen somewhere and add an errant waypoint at the end of the mission.

 

[Billie Nelson]

Stuff like this sometimes happen when you are editing a mission and accidentally touch the screen somewhere and add an errant waypoint at the end of the mission.

Thankfully the Litchi screen on my mobile device is locked by default to prevent erroneous waypoint creation on the touch screen. Since I haven't yet created any flight plans on a mobile device, it is possible that Litchi's auto-locked screen is a default safeguard to write-protect all flight plans written with the Litchi Mission Hub on a desktop computer indoors.

My only minor pet peeve with the Litchi Mission Hub flight-planning screen, is that very light touches on the mouse create unintended waypoints whose erasure with an "undo" option is not possible without deleting the entire flight plan to start over on a clean map. On that note, If anyone is aware of a "delete most recent waypoint" menu option in the Litchi Mission Hub, I would be grateful for any pointers that can be shared about where to locate it.

 

[bsartist]

Thankfully the Litchi screen on my mobile device is locked by default to prevent erroneous waypoint creation on the touch screen. Since I haven't yet created any flight plans on a mobile device, it is possible that Litchi's auto-locked screen is a default safeguard to write-protect all flight plans written with the Litchi Mission Hub on a desktop computer indoors.

My only minor pet peeve with the Litchi Mission Hub flight-planning screen, is that very light touches on the mouse create unintended waypoints whose erasure with an "undo" option is not possible without deleting the entire flight plan to start over on a clean map. On that note, If anyone is aware of a "delete most recent waypoint" menu option in the Litchi Mission Hub, I would be grateful for any pointers that can be shared about where to locate it.

Indeed the lock option was added a few versions back as a safeguard for just this problem - esp on mobile devices - and has vastly improved it.

But not eliminated it. It can still happen. You sometimes need to unlock to make a change and you are vulnerable. Maybe you want to change the cruising speed. A common one for me is when I want to change something on all waypoints. I unlock, then go to tap the small select all icon. If I miss - boom: new waypoint way out there somewhere.

 

[RotorWash_UAV]

I use “go back to waypoint 1.”

Same here, with WP1 set near my HP. Has worked well so far.

 

[Billie Nelson]

This picture from the video that was rolling during that fateful descent, shows the reflection of the drone as it landed within inches of the parked car. In the background, and less than ten feet away, is the table I use for takeoffs and landings, to ensure the drone never lands on dirt or grass.

I babied this drone ever since I bought it, always landing manually and with the greatest of care, so it just broke my heart to have this happen, all due to a moment of carelessness. The landing would have been gentle enough if the damned car wasn't in the way, and when I looked the drone over, two of those plastic pins that hold on the camera gimbal bushings, were sheared off, leaving the bushings in place.

Replaced the plastic pins, but left the bushings alone as they appeared intact. I also replaced two of the props that were obviously scarred from hitting the floor of the car, yet, for the first time since I bought this drone new in 2016, video footage from subsequent flights shows really bad jello. I'll replace all the props now, but if the jello persists, the drone will have been reduced from a very stable camera platform, to a garden toy whose footage is of little practical use. This is one very costly lesson learned for sure.

 

[bsartist]

How many pins do you have installed now? Two or four?

I’m wondering if maybe you saw two pins intact and thought there should be four and added two more. If this is the case, take those two back out. There should only be two - diagonally across. When I have had bad jello it was due to improper pin placement in those bushings.

 

[Billie Nelson]

Holy Toledo ! Two pins only ? I just installed two pins in the bushes that had none, under the assumption that the crash landing had somehow sheared off two pins. I'm right at this moment watching video taken with all four pins in place, and the jello is gone completely, leading me to conclude that my "fix" was the cure for the jello vibration I saw yesterday.

Now that I understand there were only two pins to begin with, I am at a loss regarding which pins need to be removed, to restore this craft to the stock configuration. Truth be told, I never did closely examine the pins and bushes on this craft prior to the crash landing, so this clarification is very much appreciated. I'll now need to look online for some closeup pictures of the camera gimbal, so I don't remove the wrong two pins.

Now I know why it is that I didn't see any broken pins on the ground, when I looked over the area that the drone landed, having moved the car away to get a better look. The pins never existed in the first place. Most likely, it was incorrect pin placement that caused the jello, as you have observed in the past with your drones.

Despite having logged over 70 cumulative miles of autonomous flight with this drone over the past month alone, my knowledge about its design, is still very limited. One thing for certain, is that I don't expect to ever crash this drone again, knock on wood.

 

[Billie Nelson]

Ok I went over my library of youtube videos, and found a closeup picture that clearly shows which two pins to retain, and which to remove. Much thanks Bill, for this timely caution about a design feature that I almost certainly would have overlooked as I bumbled along duking it out with the jello monster.

 

[bsartist]

Holy Toledo ! Two pins only ? I just installed two pins in the bushes that had none, under the assumption that the crash landing had somehow sheared off two pins. I'm right at this moment watching video taken with all four pins in place, and the jello is gone completely, leading me to conclude that my "fix" was the cure for the jello vibration I saw yesterday.

Now that I understand there were only two pins to begin with, I am at a loss regarding which pins need to be removed, to restore this craft to the stock configuration. Truth be told, I never did closely examine the pins and bushes on this craft prior to the crash landing, so this clarification is very much appreciated. I'll now need to look online for some closeup pictures of the camera gimbal, so I don't remove the wrong two pins.

Now I know why it is that I didn't see any broken pins on the ground, when I looked over the area that the drone landed, having moved the car away to get a better look. The pins never existed in the first place. Most likely, it was incorrect pin placement that caused the jello, as you have observed in the past with your drones.

Despite having logged over 70 cumulative miles of autonomous flight with this drone over the past month alone, my knowledge about its design, is still very limited. One thing for certain, is that I don't expect to ever crash this drone again, knock on wood.

Maybe look closely at the picture of the reflection from your video before the crash. And remember it’s a mirror image.

But my guess is that it doesn’t matter as long as they are diagonal.

 

[bsartist]

Ok I went over my library of youtube videos, and found a closeup picture that clearly shows which two pins to retain, and which to remove. Much thanks Bill, for this timely caution about a design feature that I almost certainly would have overlooked as I bumbled along duking it out with the jello monster.View attachment 120678

Glad to help.

 

[Bone4Drone]

Having run many successful long range Litchi missions lasting until the battery drains down to 30% over 20 minutes on average, I became complacent, and paid less attention to detail, such as that all-important "Settings" option that MUST be set to have the drone do "Nothing", and NOT do an RTH landing on arrival at the launch point.

With growing confidence in the estimated flight time calculated for each mission by the Litchi Mission Hub, I had developed a habit of noting the takeoff time, adding to that the estimated flight duration, and then going indoors, with the intention of stepping outside exactly 5 minutes before the drone's estimated time of arrival, to disengage the autopilot and manually land the craft. Now this routine had worked perfectly for well over twenty long-range autonomous flights, only for me to get a rude awakening today.

I was sitting indoors at my desktop computer with an eye on the clock, when suddenly, TEN minutes before the drone's expected time of arrival, I heard what sounded like a lawn mower running over a patch of gravel, and then in the same instant, realized that my drone had made a full RTH , and inexplicably scuttled underneath a car parked near my landing pad.

I killed the engines on the remote as I sprinted outside, but those props did impact the floor of the car, and the ground. To describe my mood as dismayed, would be an understatement. I had just affixed a brand new set of props this morning, and already, two of them look as though I tried to mow the lawn with the drone.

After observing the requisite few moments of hair-pulling and rabid teeth-gnashing, I set the drone on my takeoff table, and punched the throttle. The bird lifted up into a dead stable hover, with no immediate indication of any lasting damage resulting from my act of monumental idiocy. None of the props are cracked, but any motor damage that may have been incurred probably won't become apparent until I run a proper test flight within visual range, tomorrow, when I recover from the shock of this debacle.

Moral of story, ALWAYS set your drone to do "Nothing" on arrival at the final waypoint. I was warned about this setting just two days ago in this forum, yet once again, I overlooked that setting, and launched the drone, confident that since all my altitudes had been meticulously cross-checked, nothing could possibly go wrong. Henceforth, I will also remain outdoors for the entire duration of every future flight, and will NEVER rely on the flight time figures from the Litchi Mission Hub since they are after all, subject to wind variations aloft. Wow ! What a day.

Great story and a good heads up for others to never go AWOL when their bird is on a mission. My problem is actually kind of the opposite...I stand there and "white knuckle" the controller until it's safely on the ground.

I created a Litchi mission and flew it a couple weeks ago that almost ended my illustrious career as a drone pilot. The mission was designed to fly about 100 yards and then orbit a 50ft monument in a fairly tight circle. When I started the mission, the drone lifted off and flew quite fast to the monument. So far, so good. But it headed right for the monument and would have crashed right into it but the crash avoidance sensors kicked in to save it. It stopped abruptly and just hovered in place with a slow tendency to lose altitude.

Like an idiot, I tried it again with the same exact result. This time my wife was standing pretty close to the monument and told me that when the P4P put the brakes on, it's inertia carried it forward to within a foot or two of crashing into the granite structure. This had me stumped for a while. Re-checked my settings and I noticed that one had somehow changed...the one that tells the drone what direction to approach the monument to begin the orbit. It was trying to fly thru the structure to get to the other side! I changed the setting to "Nearest point" and it performed the mission flawlessly.

 

[Billie Nelson]

Bone4Drone, your near-miss provides yet further incentive to check and double check every detail of all flight plans created on the Litchi Mission Hub. It is so easy to become complacent after a few hundred miles of Litchi missions are under a drone pilot's belt, and for this reason I developed the habit of repetitively scrutinizing altitude settings and other key flight parameters, prior to tapping the launch button.