Simulated Litchi mission to ascend a 9000 ft mountain peak will not accept waypoint altitude gains beyond 1640 vertical ft above the home point???

Given the info, one approach to my mission then might be to ascend to 400 vertical feet at my take off point before I set the RTH location. I would then be able to ascend the mountain a maximum of 400 + 1640 = 2,040, which theoretically from my take off elevation of 7000 ft, would get me to 9000 ft near the summit. Has anyone tried to set a home point while hoovering? and if so, how did you do it?
Have you considered conquering much higher mountain peaks? The challenge, of course, would be having the battery power to do it. So, what if you carefully planned out the task by taking off from the base and landing at pre-determined locations every 1500 to 1640 feet. Then take off again and have a helper every few miles to change out your battery. Then take off again and repeat until you have reached to summit. Be spectacular with DJI goggles. Goofy, I know, but could be fun on a really high mountain. Everest anyone?
 
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Forgive my ignorance but I'm trying to wrap my brain around this curious point. As I understand it, my DJI P4Pv2 will always "think" it's flying at a height relative to it's takeoff point elevation. So, I could takeoff from a 5,000ft mountain peak and ascend to a height of 400ft, then fly horizontally out over a valley, for instance. The drone would think it's flying at 400ft altitude
The drone doesn't "think" it's 400 feet above the ground.
It knows that it is 400 ft higher than the launch point.
It's up to the flyer to handle the difference between the indicated height and the actual height above the ground below it.
Or, does my DJI bird begin a freefall as I go further away from my launch point as it somehow "knows" the ground has gotten farther away than 1640ft? Would the drone begin descending once it somehow "sensed" an altitude of over 1640ft?
This is a common question for flyers who only got their drone last week.
Your drone has no way to know whether the ground below is 50 ft away or 5000 ft away.
Its only height reference is height relative to the launch point so of course it won't descend in that situation.
It's a flying machine, not a terrain following machine.
 
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To answer some of the above questions:

The P4 has a 'service ceiling' (whatever that is) of 6,000 metres (19,685 feet), but I've seen video of one successfully launched and flown from higher than that. However, the drone won't ascend more than 500 metres above the home point - irrespective of how high it is off the ground at the time.

As it doesn't know where the ground is (once its downward vision sensors are out of range), it won't stop you from flying more than 500 metres above the ground if the ground were to drop away.

As far as I'm aware, you can't reset the home point without landing. As Meta4 described, it would be a tricky operation to do so while flying up a mountain.

In case you were wondering, there's no software limit on how far you can descend: Hence, you can launch from the side of a mountain and fly down without being stopped.
 
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Having covered over 2,094 cumulative miles of fully autonomous Litchi missions with my Phantom 3 Standard and my venerable Mavic Pro1, I observed a distinct variation in the accuracy with which programmed altitudes above waypoint elevations were flown by Litchi. When I launched the drones from a point with a higher elevation than all successive waypoints, the drone flew about 20 feet higher than expected, which worked out fine, as I was then able to then fly successive missions with progressively lower assigned altitudes until my optimal cruise altitude of 150 feet AGL was attained.

The one time I launched my Mavic Pro1 from a location that was lower than the successive waypoints of the mission, the drone flew a whopping 50 feet LOWER than anticipated, which put the Mavic Pro on a direct collision course with a palm tree en-route, at which point obstacle avoidance kicked in and the drone spun around and made a bee-line for home without completing the waypoint sequence. If I had flown my Phantom 3 Standard on that day, the craft's inability to avoid obstacles would have ensured that it slammed into that tree, never to be found again, and for a reason that would have eluded me to this day.

The upshot of this cautionary tale is that Litchi flies the drone significantly lower than the programmed altitude above terrain when the launch point lies below the destination waypoints. I suspect that sending the drone up a steep mountainside will likely exacerbate that altitude error thereby virtually ensuring that a CFIT ( Controlled Flight Into Terrain) will occur for any drone that is not equipped with obstacle avoidance capability.
 
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DJI SDK Limits:

Min-Max 3D distance between 2 WPs: 0.6-1999m (2-6561ft)
Max distance between Home and WP: 4000m (2.48mile)
Max Cumulative mission distance: 30000m (18.64mile)
Min-Max Corner radius of waypoint: 0,2-1000m (0.6-3280ft)
Min-Max Orbit Raduis: 15-500m (49-1640ft)
Min-Max WP Height: -200-+500m (-656-+1640ft)
Min-Max POI Height: -200-+500m (-656-+1640ft)

Min-Max Mission Waypoints: 2-99
Max number of actions per waypoint: 15
Max number of times a single waypoint action can be repeated: 15
Min-Max Pause setting in WP-action: 0-32 sec. (0-32767 ms)
Rotate UAV in WP-action: -180°, +180°
Controllable Gimbal range: (-90° to +30°), -90° to +0°

For Gimbal Pitch changes and Flying Speed Changes to work there MUST be a connection between the AC and RC.

The altitude of the aircraft is relative to the ground at the take-off location, has a range of [-200,500] and should not be larger than the aircraft's max limited altitude. If two adjacent waypoints have different altitudes, then the altitude will gradually change as the aircraft flies between those waypoints.
 
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DJI SDK Limits:

Min-Max 3D distance between 2 WPs: 0.6-1999m (2-6561ft)
Max distance between Home and WP: 4000m (2.48mile)
Max Cumulative mission distance: 30000m (18.64mile)
Min-Max Corner radius of waypoint: 0,2-1000m (0.6-3280ft)
Min-Max Orbit Raduis: 15-500m (49-1640ft)
Min-Max WP Height: -200-+500m (-656-+1640ft)
Min-Max POI Height: -200-+500m (-656-+1640ft)

Min-Max Mission Waypoints: 2-99
Max number of actions per waypoint: 15
Max number of times a single waypoint action can be repeated: 15
Min-Max Pause setting in WP-action: 0-32 sec. (0-32767 ms)
Rotate UAV in WP-action: -180°, +180°
Controllable Gimbal range: (-90° to +30°), -90° to +0°

For Gimbal Pitch changes and Flying Speed Changes to work there MUST be a connection between the AC and RC.

The altitude of the aircraft is relative to the ground at the take-off location, has a range of [-200,500] and should not be larger than the aircraft's max limited altitude. If two adjacent waypoints have different altitudes, then the altitude will gradually change as the aircraft flies between those waypoints.
Interesting stats. Curious if it is possible to fly a cumulative mission distance of 18.64 miles without running the battery down first.
 
Holy Cow Bone4Drone. If your age is as stated, then I'll have a double helping of what you ordered, with onion rings on the side.
 
As far as I'm aware, you can't reset the home point without landing.
There's no problem resetting the home point in flight.
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But that does not reset the zero height reference, which can only be done by landing the drone.
 
Holy Cow Bone4Drone. If your age is as stated, then I'll have a double helping of what you ordered, with onion rings on the side.
I apologize, Billie. I thought they were asking for my 'apparent' age. My 'feels like' age is considerably younger...like around 97 or so.
 
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There are parameters controlling the max height that can be modified by DJI Assistant v2 that work for legal mountain climbing below 400’ AGL on the P4P. Not sure if the P4P V2 has the same capability, but it is definitely worth looking into.
 
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There are parameters controlling the max height that can be modified by DJI Assistant v2 that work for legal mountain climbing below 400’ AGL on the P4P. Not sure if the P4P V2 has the same capability, but it is definitely worth looking into.
Could you direct me to where I can find out more about how to do that? Thanks
 

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