Mavic some log values?

[ad60]

Hello, everyone. I am a new member and I'm very happy to join this platform. I'm going to use a DJI Mavic air 2 for my university project and can I get rpm, thrust and torque values in the Mavic's in-flight log?

 

[cameracamel]

Hello, everyone. I am a new member and I'm very happy to join this platform. I'm going to use a DJI Mavic air 2 for my university project and can I get rpm, thrust and torque values in the Mavic's in-flight log?

Welcome from across the pond!

 

[ad60]

Welcome from across the pond!

Thank you so much across the pond

 

[MA2 317]

Hello from the Crossroads of America ad60.

There are members here that can get into the nitty gritty of the flight logs, unfortunately I'm not one of them.

There are options to retrieve the logs that will give you basic information about a flight but reading the x y z values of a flight is above my pay grade.

Follow the instructions from this site to retrieve a flight log and see what you think.

DJI Flight Log Viewer | Phantom Help

Upload and view flight logs from your DJI drones

www.phantomhelp.com

Another site would be AIRDATA.

Drone Data Management and Flight Analysis | Airdata UAV

Need an easier way to manage and analyze drone flights? Get notified of potential problems, keep up with drone maintenance, and create customized reports with Airdata UAV. Sign up today!

airdata.com

Both are free to use but if you spend some money on the flight reader, you can get more details about the flight

Good luck and welcome to the Forum.

.

 

[ad60]

MA2 317" data-source="post: 1642936" class="bbCodeBlock bbCodeBlock--expandable bbCodeBlock--quote js-expandWatch">

Hello from the Crossroads of America ad60.

There are members here that can get into the nitty gritty of the flight logs, unfortunately I'm not one of them.

There are options to retrieve the logs that will give you basic information about a flight but reading the x y z values of a flight is above my pay grade.

Follow the instructions from this site to retrieve a flight log and see what you think.

DJI Flight Log Viewer | Phantom Help

Upload and view flight logs from your DJI drones

www.phantomhelp.com

Another site would be AIRDATA.

Drone Data Management and Flight Analysis | Airdata UAV

Need an easier way to manage and analyze drone flights? Get notified of potential problems, keep up with drone maintenance, and create customized reports with Airdata UAV. Sign up today!

airdata.com

Both are free to use but if you spend some money on the flight reader, you can get more details about the flight

Good luck and welcome to the Forum.

.

Hello and thank you very much for your response MA2 317.
I found the flight log records for Mavic air 2 and opened them through the csv app. I found the rpm, current, voltage... values for each motor in it. However, unfortunately, I couldn't find or see the thrust and torque values. I am waiting for the help of forum members who know the log records in detail. Thank you for your attention MA2 317.

 

[slup]

...However, unfortunately, I couldn't find or see the thrust and torque values.

Those aren't in any of the logs generated by DJI drones... you need a test stand with a thrust & torque sensor to measure these.

 

[ad60]

Those aren't in any of the logs generated by DJI drones... you need a test stand with a thrust & torque sensor to measure these.

Thank you so much for reply slup ! Bad news. Maybe I can use mathematical equations to convert from rpm graphics to torque graphics. But I don't know of any method that can transition to thrust. I guess there's no other way.

 

[BudWalker]

Hello, everyone. I am a new member and I'm very happy to join this platform. I'm going to use a DJI Mavic air 2 for my university project and can I get rpm, thrust and torque values in the Mavic's in-flight log?

Perhaps you could say a little more about your project?

Are you talking about individual motor/prop thrust? I suspect that motor RPM is mostly linear with thrust. Might be difficult to determine units though.

Similarly, is it individual motor/prop torque or airframe torque?

 

[ad60]

Perhaps you could say a little more about your project?

Are you talking about individual motor/prop thrust? I suspect that motor RPM is mostly linear with thrust. Might be difficult to determine units though.

Similarly, is it individual motor/prop torque or airframe torque?

In my project,I just want to measure thrust and torque values. Thank you for your reply Bud Walker. Yes I am talking about individual motor torque and thrust, not airframe.

 

[slup]

In my project,I just want to measure thrust and torque values. Thank you for your reply Bud Walker. Yes I am talking about individual motor torque and thrust, not airframe.

Here you have a guy that measure this in the proper way & what equipment he uses...

 

[BudWalker]

In my project,I just want to measure thrust and torque values. Thank you for your reply Bud Walker. Yes I am talking about individual motor torque and thrust, not airframe.

You could get close to measuring thrust as a function of motor RPMs. Attach a weight on a cord tied to the airframe. Try to get it close to the CG. When the AC is hovering the total thrust will be the attached weight + airframe weight. Thrust / RPM for a single motor will be

((attached weight +airframe weight) / 4) / average RPM

Now do this for different attached weights. This should result in multiple (thrust, RPM) points. Then fit a curve to the points.

We don't have to consider drag since the airframe will be stationary in hover.

Torque would be harder.

 

[Yorkshire_Pud]

Is this a university project ?
As a very crude approximation you probably have the power delivered by the battery, via current and voltage data. If you have rpm data you have enough to come up with approximate torque values.
Approximate because the battery is also supplying the power used in the drone's electronics etc..

I think some sort of test rig, such as that video shows, would be much better because the drone may continually change motor speeds and thus accelerations may interfere with your measurements.
With a test rig you would, I think, be more likely to encounter steady state conditions.

I doubt they would release the data but have you thought of asking DJI or having your supervisor ask DJI, or would that defeat the purpose of the project ?

I am guessing that the drone would shut the motors down if only one prop is installed.

 

[Yorkshire_Pud]

Here you have a guy that measure this in the proper way & what equipment he uses...

Nice find.