Throttle difference ? ATT vs GPS vs Manual Mode ???

[helloman1976]

I don't mean to resurrect and old thread; but, I've been having some issues with throttling revving when switching to manual mode even during bench testing without props (WKM FW 5.26). I understand that I can set up an individual throttle curve for each flight mode. But, there's something strange going on that I don't understand. If I do CSC in manual mode and then switch to either atti or gps, there's no significant change in motor rpm, regardless of how many times or in what order I switch between the different flight modes. However, if I do CSC in either atti or gps mode, and then switch over to manual mode, there is a significant revving of the motors, and it happens every time I switch over the manual mode. If I switch back to gps or atti, the motors go back to normal rpm. Any ideas about what's going on here?

I don't know the WKM module well at all but unless you can setup a throttle curve inside of its programming I wouldn't mess with that. Setting up a throttle curve on your copter is a big NO NO. Can it be done? Sure, but with consequences. You'll never have centered sticks for example and there a myriad of problems that come with that alone.

The proper way to setup your copter when using it with a NAZA (WKM might be different) to avoid that revving is to make sure you can hover at 50% throttle in manual mode. I personally change my props to make this happen. If I hover at 50% in manual mode and I switch to GPS/ATT mode then there will be no change in power because 50% in GPS mode IS hover and so if they match, no power change. If I hover at 40% in manual mode and switch to GPS/ATT mode it'll drop like a rock and you'll have to "catch it" from falling, this is completely normal. Manual mode disables ALL compensation, that's the point of it. You could also call manual mode "sport mode" and that would be appropriate as well. Your settings will depend entirely on your setup and no-one will be able to tell you which settings are too low or too high for your setup, they'll only be able to get you close. You'll have to fly it to see if it's to your liking and if it's flying stable like you want. There are no standards when it comes to settings, only preferences.

 

[PeterLester]

Thanks ZacAttack and Helloman1976....
I've had these issues with both NAZA and WKM and often wondered why this issue persisted. I thought it would be possible for the FC to achieve a bumpless transfer of throttle setpoint between all three modes but there is more to it than that. Summary: achieve hover at 50% thottle in manual mode.... the rest should take care of itself.

 

[helloman1976]

Thanks ZacAttack and Helloman1976....
I've had these issues with both NAZA and WKM and often wondered why this issue persisted. I thought it would be possible for the FC to achieve a bumpless transfer of throttle setpoint between all three modes but there is more to it than that. Summary: achieve hover at 50% thottle in manual mode.... the rest should take care of itself.

Correct just make sure you do that with something other than the transmitter. Your trims should never be moved if you are flying a NAZA/WKM based system, you should have no throttle curves and no EXPO etc....can you do those things? Sure...but you'll pay for it with consequences.

Achieve 50% hover in manual mode, then when you switch over it is seamless. You can do a number of things and they can "work" but what you want is for things to work "properly" and not just "work".

 

[econfly]

The radio's throttle should be centered in the NAZA or WKM assistant when the stick is literally centered on the radio. If not, calibrate the throttle in the assistant software. At that center position, ATTI and GPS modes should hold the copter at the present height. Throttle over 50% (above center) should increase height. Below center should decrease it. At center should hold altitude. If that doesn't work then the copter is not properly built (way under/over propped), the vertical gain is way off, or the NAZA/WKM is not seeing a centered throttle when the stick is literally centered.

When you switch to manual, the response to throttle changes completely. The NAZA or WKM just passes along the throttle position to the ESCs. 50% throttle can mean total thrust greater than weight (copter will rise) or less (copter will fall).

So, holding positing in ATTI or GPS mode in a properly setup system requires the throttle to be centered. Switching to manual with a centered throttle can result in the unit responding by increasing or decreasing altitude. All perfectly normal. Some say a well-designed build should hold height at about 50% throttle. That's fine, but an aside.

Likewise, flying at steady altitude in manual mode may (almost certainly will) imply a throttle stick not exactly at 50%. So switching back to ATTI or GPS with the throttle at any position other than 50% is going to result in altitude change -- and it will keep going up/down until the stick is moved back to center. Again, perfectly normal.

What some here correctly suggest is a throttle curve (or shift) that is linked to the ATTI/GPS/Manual switch. The curve is active in manual mode only (linked to the mode switch) and is such that the throttle signal is where it needs to be to hold altitude with a centered stick. This is all done on the radio and almost has to be calibrated by flying and testing. The idea is to have manual mode hold altitude with the throttle centered. This will not be perfect. Pack voltage variation in particular will affect the results over the span of a single flight.

All of this makes the most sense if you use (or imagine) a radio with a spring loaded throttle stick that returns to center when released (like is now standard with Phantoms). In ATTI or GPS mode that centered stick means the NAZA/WKM should hold height. But in manual mode it just means 50% throttle by default.

In sum, if the copter is not holding altitude at mid throttle in ATTI or GPS mode then there is a problem with the build, power, or setup in the NAZA/WKM assistant software. Altitude response to mode change to/from manual is normal, but can be imperfectly addressed by linking a throttle curve (or shift) to the mode switch in manual, and this is done entirely on the radio.

 

[ZacAttack]

The radio's throttle should be centered in the NAZA or WKM assistant when the stick is literally centered on the radio. If not, calibrate the throttle in the assistant software. At that center position, ATTI and GPS modes should hold the copter at the present height. Throttle over 50% (above center) should increase height. Below center should decrease it. At center should hold altitude. If that doesn't work then the copter is not properly built (way under/over propped), the vertical gain is way off, or the NAZA/WKM is not seeing a centered throttle when the stick is literally centered.

When you switch to manual, the response to throttle changes completely. The NAZA or WKM just passes along the throttle position to the ESCs. 50% throttle can mean total thrust greater than weight (copter will rise) or less (copter will fall).

So, holding positing in ATTI or GPS mode in a properly setup system requires the throttle to be centered. Switching to manual with a centered throttle can result in the unit responding by increasing or decreasing altitude. All perfectly normal. Some say a well-designed build should hold height at about 50% throttle. That's fine, but an aside.

Likewise, flying at steady altitude in manual mode may (almost certainly will) imply a throttle stick not exactly at 50%. So switching back to ATTI or GPS with the throttle at any position other than 50% is going to result in altitude change -- and it will keep going up/down until the stick is moved back to center. Again, perfectly normal.

What some here correctly suggest is a throttle curve (or shift) that is linked to the ATTI/GPS/Manual switch. The curve is active in manual mode only (linked to the mode switch) and is such that the throttle signal is where it needs to be to hold altitude with a centered stick. This is all done on the radio and almost has to be calibrated by flying and testing. The idea is to have manual mode hold altitude with the throttle centered. This will not be perfect. Pack voltage variation in particular will affect the results over the span of a single flight.

All of this makes the most sense if you use (or imagine) a radio with a spring loaded throttle stick that returns to center when released (like is now standard with Phantoms). In ATTI or GPS mode that centered stick means the NAZA/WKM should hold height. But in manual mode it just means 50% throttle by default.

In sum, if the copter is not holding altitude at mid throttle in ATTI or GPS mode then there is a problem with the build, power, or setup in the NAZA/WKM assistant software. Altitude response to mode change to/from manual is normal, but can be imperfectly addressed by linking a throttle curve (or shift) to the mode switch in manual, and this is done entirely on the radio.

Thank You!! That's all I was trying to say. Use your throttle curves, your Dual Rates and your TX to it's max. potential. I change fro GPS to ATTI. to MM at %50 stick with no altitude variation whatsoever. It's al done in the TX. Also, Expo and Dual Rates can be applied to each mode via your TX-(GPS/ATTI/MM).

 

[ZacAttack]

Correct just make sure you do that with something other than the transmitter. Your trims should never be moved if you are flying a NAZA/WKM based system, you should have no throttle curves and no EXPO etc....can you do those things? Sure...but you'll pay for it with consequences.

Achieve 50% hover in manual mode, then when you switch over it is seamless. You can do a number of things and they can "work" but what you want is for things to work "properly" and not just "work".

Please explain why you say "you should have no throttle curves and no EXPO.....you will pay it with consequences"?? Really? Been running Expo, Dual Rates and Throttle Curves for over 12months now with my Naza/Naz V2...So please explain!!!!!!THANKS!!!!. I cannot Fly the F450 in Manual Mode safely without taming the mode via Dual Rates and Expo. My TX is a JR 9503 RX R921 DSMX, if anyone is interested or need help with their TX..ASK. Don't believe everything you hear. Cheers Guys!!

 

[ZacAttack]

Thanks ZacAttack and Helloman1976....
I've had these issues with both NAZA and WKM and often wondered why this issue persisted. I thought it would be possible for the FC to achieve a bumpless transfer of throttle setpoint between all three modes but there is more to it than that. Summary: achieve hover at 50% thottle in manual mode.... the rest should take care of itself.

Yes, adjust with a throttle curve assigned to that Mode so your hovering at %50 in MM, the other modes GPS/ATTI automatically hovers at %50 regardless. The only way to find out your REAL TIME hovering point with your current Power System installed is in Manual Mode with the DJI Naza FC. You can and will need DualRates and Expo to tame down the flight characteristics of MM. It is super Sensitive to stick control.

 

[ChopperAddict]

throttle issues with JR DSX9 on 550 with Naza M

Please explain why you say "you should have no throttle curves and no EXPO.....you will pay it with consequences"?? Really? Been running Expo, Dual Rates and Throttle Curves for over 12months now with my Naza/Naz V2...So please explain!!!!!!THANKS!!!!. I cannot Fly the F450 in Manual Mode safely without taming the mode via Dual Rates and Expo. My TX is a JR 9503 RX R921 DSMX, if anyone is interested or need help with their TX..ASK. Don't believe everything you hear. Cheers Guys!!

Hi

As requested, I am ASKING

I am rebuilding the gear I had in a 450 into a 550, and have my radio set up so that modes and IOC all work great, I have the Rudder DR set to give total Fail/Safe. So far - great, BUT....

With no props on at all, my throttle gives me a progressive increase in motor revs, BUT above halfway, next to nothing, so I can just about get to the hover, but that is it. Not very useful eh ?

It is pretty well the same in all 3 modes, and I have a throttle curve as a straight line - 100 to +100.

My autopilot settings are :
Basic 145, 145, 145, 150
Attitude 130, 130

Any help with this would be so gratefully received.

Cheers
Ian

 

[gtranquilla]

The speed response you are experiencing I believe is typical when there is no load on the motor. When you put the props on you will see rpm continue to increase after 50% throttle.
Reason: It's all about the motor torque speed curves. If you have the time and interest.... review the following to better understand why speed reaches peak sooner when there is no load on the motor.
http://lancet.mit.edu/motors/motors3.html

Notice the situation when there is no load on the motor, at the 1/2 way point as per the following formulas:
Due to the linear inverse relationship between torque and speed, the maximum power occurs at the point where W = ½ Wn, and T = ½ Ts.
at the end of section 3.1

Hi

As requested, I am ASKING

I am rebuilding the gear I had in a 450 into a 550, and have my radio set up so that modes and IOC all work great, I have the Rudder DR set to give total Fail/Safe. So far - great, BUT....

With no props on at all, my throttle gives me a progressive increase in motor revs, BUT above halfway, next to nothing, so I can just about get to the hover, but that is it. Not very useful eh ?

It is pretty well the same in all 3 modes, and I have a throttle curve as a straight line - 100 to +100.

My autopilot settings are :
Basic 145, 145, 145, 150
Attitude 130, 130

Any help with this would be so gratefully received.

Cheers
Ian

 

[ChopperAddict]

Many thanks indeed, and well done indeed sir, you are spot on. I fitted a set of 10" blades and presto, I could see and feel the difference. I am a happy puppy for sure, although interestingly it also showed me that 3 out of 4 of the original quad DJI motors are screwed up, grating and stopping etc, after only 3 flights in the 450 - not good eh ?

One final question for you. I know what the NAZA start up noises should sound like, but I do not get any of them. It used to have those loud noises in the quad frame. All I am getting is just the radio initialization noises. The LED on NAZA is showing correct mode lights etc. But it would be really good to know audibly that NAZA has initialized correctly.

Any ideas on that.

Best
Ian

 

[Benjamin Kenobi]

Hi Ian!

The initialization noises come from the motors (I know you know that already :tennis. Are your motors connected? It is odd if not making these noises.

Regarding your previous post, you'll also notice in ATTI and GPS mode that the throttle is not linear below 50% as the motors just idle. Some kind of DJI safety feature to prevent inputs on the ground.

Hope this helps!

 

[ChopperAddict]

Hi

Right now I have 4 motors out of 6 connected (waiting for 2 more to arrive to replace the duff DJI units) Maybe it will do the loud beeps when all 6 are on board ? I would of thought just the 4 would make a good loud noise, but I have to listen quite carefully to hear them at all. Is it just the normal ESC init noises that are made, I got the impression that the NAZA or MU made their own noises ?
Cheers
Ian

 

[Benjamin Kenobi]

Hey. It shouldn't make a difference (in my mind) if not all motors are connected, a bit quieter maybe. It is the motors that make the noise and not the ESC or NAZA. That I'm sure of!

 

[gtranquilla]

Review your system configuration, typical NAZA sounds etc. by reviewing these YouTube videos: 1,2 and 3
http://www.youtube.com/watch?v=ck3tu-4UVgg

The ESCs will each beep on startup when properly configured with the rest of the system. I don't recall the NAZA ever beeping however.
If you had any crashes or flips previously the motors and/or escs are easily damaged. If just a mild flip, dirt can get between the motor bell and the rotor causing a grating sound.
For testing and troubleshooting escs/motors without the radio I use one of the following: http://www.hobbyking.com/hobbyking/...rvo_Tester.html?strSearch=turnigy servo teste

Most motors are easy to maintain and repair but I found it too difficult to disassemble the DJI motors that come with the F550.