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Litchi waypoint mission/what happens after loss of signal?

Humanparody

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Self explanatory title. My house and neighborhood is riddled with sources of wifi interference and, as such, my flights out past 1500 feet usually end up with severe signal drop-off. I'd like to set up a litchi mission and have it run the mission out past where I can typically fly manually. What happens when I get to a point where the RTH would normally kick in? I don't necessarily need to see the live feed, I'd just like the recording when it gets back.
 
I bought Litchi myself just now. It says that the drone can continue its mission when it disconnects from the RC.
 
Searching around, I read a post where someone said after he lost signal, the mission completed but at half the speed it was supposed to. That one seems to be unresolved too which makes me nervous. I'm curious about if I need to have any particular settings for RTH to ensure I don't inadvertently override the waypoint mission and it won't complete, or more importantly use the wrong settings and set myself for a lost bird if something doesn't go right during the mission. Basically just looking for someone with a bit more experience on these longer missions to pat me on the back and tell me it will be okay.
 
Searching around, I read a post where someone said after he lost signal, the mission completed but at half the speed it was supposed to. That one seems to be unresolved too which makes me nervous. I'm curious about if I need to have any particular settings for RTH to ensure I don't inadvertently override the waypoint mission and it won't complete, or more importantly use the wrong settings and set myself for a lost bird if something doesn't go right during the mission. Basically just looking for someone with a bit more experience on these longer missions to pat me on the back and tell me it will be okay.
Unfortunately I bought Litchi last night, and haven't had a chance to test it. I'm in a very mountainous and tree riddled area which results in lots of interface from the controller. I usually only get up to 2k before my connection craps out.
 
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litchi waypoint mission what happens after loss of signal.
As per the second sentence in the Litchi Waypoint help.. "..the aircraft will fly from waypoint to waypoint and complete the mission even if the signal is lost. "


What happens when I get to a point where the RTH would normally kick in?
The Waypoint Mission stops and a standard Mavic RTH procedure commences. It is precluded by a similar Warning to that which you get with DJIGo. Cant recall exactly but "Low battery - return to home will commence in 10 seconds" or similar. Probably has a cancel option too (Like Go) but when I have had it, I allowed it do the RTH. The main point to note is it does not keep trucking out on a WPT mission past where there is enough battery to get home. So you must build routes it can achieve or it will bail out on RTH prior to completion.

I'm curious about if I need to have any particular settings for RTH to ensure I don't inadvertently override the waypoint mission and it won't complete, or more importantly use the wrong settings and set myself for a lost bird if something doesn't go right during the mission.
As long as you dont override the WPT mission by toggling the Sport mode switch or pressing the RTH button it will continue on the mission. You can run in to trouble after signal loss if you get nervous and start sending commands, not knowing if they have gotten though. ie Toggle sport mode & if the message gets through it will stop and hover til low battery RTH triggers. But you may not know if the message got through. So build a route you know it can complete and sit on your hands in the LOS periods. Build you confidence by building a really close in WPT mission within a hundred meters or so. Have it fly around slowly at maybe 5 or 10 mph. Once you are happy with how it flies the route let it get under way and turn your remote of OFF place it in a garbage can to cause a signal loss. You can then see how it behaves.
 
You have to have Balls of steel to send the Mavic out like that. If the GPS signal goes haywire your SOL.
 
Just kidding, they're only steel. I don't plan on sending it out on anything ridiculous. Like I said, I have REALLY ****** reception here. I can't make it to the end of my 1/4 long street before I'm getting warnings and video blackouts.
 
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Unfortunately I bought Litchi last night, and haven't had a chance to test it. I'm in a very mountainous and tree riddled area which results in lots of interface from the controller. I usually only get up to 2k before my connection craps out.


The app confirms WILL / CAN complete missions even if lose contact with RC

upload_2017-5-3_23-22-19.png

pdf instructions
5a83f778-fff9-4d6c-b808-c49a52afe2e7

Litchi for iOS February 2017.pdf

at bottom of page 21
 
I've used Litchi to do 50+ waypoint missions, about half of which, were I lost RC connectivity.

As logger mentioned, the key is not to panic and not touch the sticks when it's out of range and to create missions carefully (check height clearance on Gearth and within battery operating limits). Also, take advantage of Litchi's mission hub when planning missions...
 
I too can confirm that Litchi missions happily complete even with total signal & video loss. You just have to be brave and wait for her to return. Its like the old lunar missions, waiting for the Applolo spacecraft to come out of blackout behind the moon :)
 
I too can confirm that Litchi missions happily complete even with total signal & video loss. You just have to be brave and wait for her to return. Its like the old lunar missions, waiting for the Applolo spacecraft to come out of blackout behind the moon :)

anyone know that accuracy of google maps .. when planing to fly around a 80mtr or 200mtr high building, the building rooftop is not in vertical position to the ground level

upload_2017-5-4_0-1-26.png

i think the only way to be safe is be on site and watch each point around the building, once its done you have a record to use for subsequent flights being sunshine, sunset and night ?

thoughts pls re the map accuracy
 
It carries on, and once it gets back within range, you will have control...do not advise though.
 
If you are planning to do it, I would say do a proper recce of the flight path and make sure your altitude is set higher than any obstacles, and that the curves do not send it in the way of something either.
 
guys thank you for asking.. this was my concern too.. about the height of the buildings obstacles what's the most accurate way to get the info? on Google Earth didn't really get it.. also another tricky thing is if you program your route on litchi hub how could u eventually know if there are electrical cables or similar? seems like the best way to create the route is from the site itself.. or am I missing something?
 
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cheers @bucefalo
I visited the building inspected from ground and roof, obviously makes it a snap when you have access to the roof.

Thee quest is what tips and tricks to find and share to tackle the challenge when you dont have access to the building, same principle as any object

I've downloaded a stack of apps to test, including apps for sunset, measurement devices but they have limits - well each ha a piece of the puzzle

The steps I'm working thru
1. establish the height; in google earth (some buildings are 3D so you can click on the roof)
or google the building specs, otherwise fly alongside and record the height of the building and surround objects/obstacles ie.,, min safe heights and if not sure add extra 10/20 mtrs and stay above everything

2. find a launch spot: about the same distance from the building as the height of the building so you have line of site
I also look for other buildings at similar distance so i can use the same launch place for several challenges

all of this seemed to be resolved with Litchi waypoints and no concern about RC signal.

Best Practice today is
create a plan on the map waypoints and test on site, tweak and then i know i have a blueprint for repeat flights for day, sunset and night.

Target buildings are 80 mtrs to 200mtrs anything

I dnt see cables as an issue as i launch in a clear spot are go to the min safe height

apps tested
HANGER 360, brilliant ... Hangar 360 Mobile App | Hangar
when launched it RACES up to optimum height 91 mtrs and fires off 23 pics in fast time
at any time u can over ride by switching to sports mode and to re engage its s.ware you have to switch out of sports mode. You can change the height and other basics which are not obvious steps.

Hangers related (main) app Autopilot Autopilot - Hangar
oozing with features (more than Litchi) so I will buy and test.

i was keen to charge on with Litchi but some of their flight modes are suspended pending bug fixes by dji (as reported in litchi site)
 
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So if you have access to the roof, why not take off from there and do a POI mode in DJIGO4? Once engaged you can move it in and out and up and down and change the speed of rotation.
 
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@baweber correct but I dnt have / get access to all so I'm gather tips/tricks to tackle the challenge and the litchi (and other apps) that offer waypoints that dnt abort when RC signal lost seems idea but as per the google earth pic of tall buildings it appears that the roof is of centre so the waypoints will not be accurate and that has varying degree of issues from missinng the pic to hitting a nearby building/obstacle. So I was wondering if someone had intel re the map of tall objects (buildings)
 
@baweber correct but I dnt have / get access to all so I'm gather tips/tricks to tackle the challenge and the litchi (and other apps) that offer waypoints that dnt abort when RC signal lost seems idea but as per the google earth pic of tall buildings it appears that the roof is of centre so the waypoints will not be accurate and that has varying degree of issues from missinng the pic to hitting a nearby building/obstacle. So I was wondering if someone had intel re the map of tall objects (buildings)
I think the best way to proceed is to visit the site and use the drone to determine the optimum path and any obstacles - go up until your image is above surrounding buildings, or determine the radius you can use without interference. Once more the DJI Waypoint app would work here. Fly the drone to the points you want and save them. And if you are working in a city with multiple high rise buildings - wind becomes a high risk factor! And starting at street level you may have GPS failure as well. Risk analysis saves drones.
 
I think the best way to proceed is to visit the site and use the drone to determine the optimum path and any obstacles - go up until your image is above surrounding buildings, or determine the radius you can use without interference. Once more the DJI Waypoint app would work here. Fly the drone to the points you want and save them. And if you are working in a city with multiple high rise buildings - wind becomes a high risk factor! And starting at street level you may have GPS failure as well. Risk analysis saves drones.

the reason we are exploring litchi is to overcome the limitation of dji go app
we can not get on the roof, we can not walk around the base of the building so the signal will be lost

Litchi waypoint system does not require RC signal (will complete without it)

The dji . POI option is not "appropriate" as it means hovering over the building which has people sitting on the roof (rooftop (open air) venues in Bangkok, which is why we want to video them.

Solution: fly in from a safe distance (line of sight) and ideally use Litchi flight mode "focus" which is currently suspended, as explained above
so the next contingency is use waypoints but we dnt know about the accuracy of the rooftops from the map as they are high up and appear to be off centre ... PLEASE REFER to my original query ... re accuracy of maps and rooftops appears to be off centre

so im seeking any intel about my query re rooftops on the map and their accuracy
 
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