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Top sensor data

Ralph thompson

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Is it possible to determine if the top IR sensors limited the ascent during an operation? I do not see any indication in the data logged in AIRDATA and with the Smart Controlled, access to the logs is restricted. I have read SAR104's excellent explanation of retrieving logs (Mavic Flt Log Analysis).
The reason is that I was operating a M2P with Smart Controller in ATTI mode indoors, all sensors including visual sensors manually turned off. In pretests I determined that the upper IR sensor still functions with all sensors turned off which of course is a good thing. (I repeated the tests with the IR sensor covered with tape and the altitude was no longer restricted). All this to photograph an ornate tiled floor top down in a new construction. I may have to repeat the flight to get additional images and would like to be confident the top sensors were functioning and preventing the M2P from crashing into the ceiling, in order to get the maximum height safely.
 
The reason is that I was operating a M2P with Smart Controller in ATTI mode indoors, all sensors including visual sensors manually turned off. In pretests I determined that the upper IR sensor still functions with all sensors turned off which of course is a good thing.
You don't give any numbers or provide data which would show what the issue is.
But when people have altitude restrictions flying in atti mode this (from p56 in your manual) is the usual explanation.

Height is restricted to 16 ft (5 m) when the GPS signal is weak and Downward Vision System is activated.
Height is restricted to 98 ft (30 m) when the GPS signal is weak and Downward Vision System is inactivated.
 
Max. altitude was 33 feet according to the log, I didn't want to get closer to the ceiling incase the top sensor wasn't working. The ceiling height was about forty feet. I'm aware of what the manual says but I'd like to see that the top sensor detected the roof and was active. In fact the Manual is not at all informative because it doesn't state that turning off all sensors still leaves the top sensor on. I have confirmed this with and without the top sensor covered. I expect there is a indicator in one of then log files (original question) that shows that the top sensor detected the ceiling and therefore prevented it from going higher. For piece of mind I'd like to see that that is the case. But maybe with the Smart Controller, its not possible to see that data. I've attached the Airdata download. I've attached a couple of images.
 

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  • Aug-31st-2021-19-15-Flight-Airdata(1).pdf
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  • 210831_UofMMIL_001.jpg
    210831_UofMMIL_001.jpg
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  • 210831_UofMMIL_017.jpg
    210831_UofMMIL_017.jpg
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Max. altitude was 33 feet according to the log, I didn't want to get closer to the ceiling incase the top sensor wasn't working. The ceiling height was about forty feet. I'm aware of what the manual says but I'd like to see that the top sensor detected the roof and was active. In fact the Manual is not at all informative because it doesn't state that turning off all sensors still leaves the top sensor on. I have confirmed this with and without the top sensor covered. I expect there is a indicator in one of then log files (original question) that shows that the top sensor detected the ceiling and therefore prevented it from going higher. For piece of mind I'd like to see that that is the case. But maybe with the Smart Controller, its not possible to see that data. I've attached the Airdata download. I've attached a couple of images.
Can you post the actual flight data rather than a pdf of just part of the data?
That would be the .txt file, or a link to either Airdata or Phantomhelp reports.
 
I tried before to upload the csv but not possible, here's the txt file.
Thanks for your help META4
 

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  • Aug-31st-2021-19-15-Flight-Airdata(1).txt
    329.5 KB · Views: 2
I tried before to upload the csv but not possible, here's the txt file.
I would need the .txt file from the controller (rather than a CSV files saved as a txt file) to see all the data fields and check whether it displays anything from the top sensors.

But what I can see is that:
You had no more than 7 satellites anytime during the flight and were in atti mode the whole time.
The bottom sensors disabled
You climbed to 10 metres and flew around gently at that height for 1:22
You maintained altitude of 10 metres well without throttle input for 1:22

In the limited information in that csv file, there's nothing to indicate anything about the upward sensors.
 
Meta4, not sure which .txt file would identify if the top proximity sensor would be turned on. I've looked through most of the .txt files on the Smart Controlled for that operation. Can you be specific please, which txt file in which folder?
 
Meta4, not sure which .txt file would identify if the top proximity sensor would be turned on. I've looked through most of the .txt files on the Smart Controlled for that operation. Can you be specific please, which txt file in which folder?
If the top sensor data is in any file, it would be the same .txt file that you uploaded to Airdata.
It will have a file name like DJIFlightRecord_2021-02-12_[15-33-10].txt
It's encoded so you won't be able to read it directly.
 
Meta4 here is the .txt file. I don't think I'm able to read this as I am totally a MAC person these days (except for the SC). Is there a way to decode this on the MAC? If you are able to see the Top Sensor data, I'd be very grateful.
 

Attachments

  • DJIFlightRecord_2021-08-31_[19-15-47].txt
    539 KB · Views: 1
Meta4 here is the .txt file. I don't think I'm able to read this as I am totally a MAC person these days (except for the SC). Is there a way to decode this on the MAC? If you are able to see the Top Sensor data, I'd be very grateful.
Here's what that flight data looks like when unencoded:

If you click the Download CSV link above the data, you'll get a large spreadsheet which shows a lot of the data that is recorded by the app.
Look along the heading row to see all the parameters.
Some are self explanatory, some are not.

I can't see any that specifically mention top sensor data.
Columns I, AE & AF are related to the downward sensors.
AZ mentions the Vision sensors.
 
Thank you Meta4, thats much more data that from the Airdata download. I see I can also access the Phantomhelp.com/logviewer, thats very useful.
Unfortunate that we can't access more data including top sensor status but there we go.
I do see in the log OSD.heightMax set to 33.8 ft and thats close to the max height achieved. Not sure why the height would be limited, maybe its just recording max alt achieved? The manual states the height is limited to 98' with weak GPS or inactive Vision system.
Many thanks for you help.
 
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