ESC calibration after every battery change

Hey guys,

Today I took my Iris+ out for the first time in months. Beautiful day today here in Ohio. Last night, I hooked up the Iris+ to mission planner to load up the stock firmware that was issued with my Iris+ when I received it last year. I had upgraded to 3.2 late last year when it was released, but had autonomous flight issues. So I put 3.1 back on, and calibrated everything. Good to go!

So fast forward to today...Getting ready to take off, slowly giving more and more throttle, when I notice the motors are not spinning at the rate at which I'm inputting into the controller. In other words, the motor speeds were not jiving with where my left stick was positioned. I removed the propellers and performed an ESC calibration right there in the driveway. No problems, took off and flew just fine. Exhausted battery and brought it down to swap batteries. Same thing happened again. ESC calibration once again. Good to go after that. This ended up happening between each battery change (four of them). Any thoughts as to what the deal is??? I'm getting ready to hook my Iris+ back up to mission planner, and reload the firmware and params again, and see what that does for me.

Another side question I have...When I had upgraded to 3.2 last year, I had issues with direction the Iris+ would face while flying autonomously. A few of you guys said it sounded like the compass just needed calibrated again. Well obviously when i took the firmware back to 3.1 the other night, I performed a compass calibration. When I took the Iris out today, same thing. The Iris points in whatever direction it wants while flying. When I first received the Iris+ last year and flew it, I had zero issues. Does the Iris have an external compass or is the compass built into the pixhawk? The reason I ask, when I'm browsing through mission planner with Iris hooked up, click on "Initial Setup", then click "Mandatory Hardware", then "Compass" The bubble labeled "Manual" is highlighted, and the drop down menu beside it says "ROTATION_NONE". Is this correct?

Thanks for taking the time to read this guys. I really appreciate any help!

Luke

I'm pretty sure the default is 3. Anyway, after you install the firmware, did you install the Iris+ Params?

(In Mission Planner, go to the Full Parameter list. On right side of screen use drop down to select Iris+, click load and a pop-up will show you which parameters will be changed - at which point you can decide to upload them to your Iris+ or not, just follow the directions on screen.)

Regarding your ESCs, something caught my attention the second time reading your post. You say you are applying throttle slowly. When you take off, in my opinion, you should give it full throttle. Its the safest way. Get it up and off the ground quickly. Less flip overs, etc. Usually I just pop it up in the air about 3 meters and then back it right off and hover there. Anyway, I mention this because the Iris+ is not perfectly weighted to center. I suppose a sharp eye might be able to perceive the different prop rotation speed - if the props are spinning slowly enough. Maybe its risky, but have you tried taking off with FULL throttle? I think you will be fine.

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Erik Graham May 4, 2015 at 11:22am

What is your way point yaw behavior parameter set to? It may have gotten reset during firmware install.

Its at the very bottom of the parameters list, search for "WP_YAW_BEHAVIOR"

You probably want it set to 3

http://copter.ardupilot.com/wiki/configuration/arducopter-parameter...
- Luke Wiseman > Erik Graham May 4, 2015 at 5:26pm
  
  Thanks for your reply Erik. I just checked, and it was set to value 2 (Face next waypoint except RTL). I will try experiementing with that parameter and see what happens. I'm assuming/guessing value 2 is the default setting that shipped with the Iris. I'll try value 3 and see what happens!
  
  Does anyone have any idea's regarding the ESC issue i'm having? I've been trying to do some research and rack my brain a bit. Unfortunately, I haven't been in the hobby nearly long enough to know the complete in's and out's of it all. Thanks guys!
- Erik Graham > Luke Wiseman May 5, 2015 at 7:46am
  
  I'm pretty sure the default is 3. Anyway, after you install the firmware, did you install the Iris+ Params?
  
  (In Mission Planner, go to the Full Parameter list. On right side of screen use drop down to select Iris+, click load and a pop-up will show you which parameters will be changed - at which point you can decide to upload them to your Iris+ or not, just follow the directions on screen.)
  
  Regarding your ESCs, something caught my attention the second time reading your post. You say you are applying throttle slowly. When you take off, in my opinion, you should give it full throttle. Its the safest way. Get it up and off the ground quickly. Less flip overs, etc. Usually I just pop it up in the air about 3 meters and then back it right off and hover there. Anyway, I mention this because the Iris+ is not perfectly weighted to center. I suppose a sharp eye might be able to perceive the different prop rotation speed - if the props are spinning slowly enough. Maybe its risky, but have you tried taking off with FULL throttle? I think you will be fine.
- Luke Wiseman > Erik Graham May 9, 2015 at 10:17pm
  
  Well I set it to option 3, and no difference. Very strange. I'm almost positive that the compass is dialed in/calibrated. I'm assuming this is a decent way to test that; when I connect to mission planner with the Iris and look at the flight data, the compass is showing the correct headings in all directions as i spin the drone. Maybe it's time to contact 3DR? Very bizzare. I haven't had any crashes or anything. On another note, you may have been on the money with ESC. Today when I flew (first time since you responded last), i gave her full throttle immediately, and had no issues. Thanks again for your input Erik!
- Luke Wiseman > Luke Wiseman May 9, 2015 at 10:28pm
  
  Im a liar! I just reviewed my flight video from earlier today. I sent the Iris on a long distance autonomous flight. I could see it the entire time, but it was just a speck in the sky, couldn't tell which direction it was facing. At the beginning of the flight, it was facing in an odd direction, then halfway through the flight, bam, it started facing towards the next waypoint! I will add that I had done another compass calibration after installing the 3.2 firmware the night before. Maybe it was finishing up its calibration during the first flight??? Anyways, I think it's safe to bring this thread to an end. Thanks again!
Luke Wiseman May 3, 2015 at 5:12pm

Yes, there are two spheres. And i do exactly that. I stop rotation, and i uncheck the box for auto complete. Fill them in as completely as I can
- Steve Foster > Luke Wiseman May 3, 2015 at 5:26pm
  
  I wonder if that calibration information is stored on the memory card IN the Pixhawk ???? Beyond me.... I've heard of some people having trouble with the memory card, but I think it's just for log files ???
- Luke Wiseman > Steve Foster May 4, 2015 at 7:04am
  
  I wonder the same thing. However, you would think, everytime I disconnect the battery (even while performing an ESC calibration), I would never be able to successfully calibrate it. It does seem like whatever memory that is responsible for saving it, is not. Hmmm
Steve Foster May 3, 2015 at 5:00pm

Do you get two spheres when calibrating the compass? There are two in the Iris+ Manual is fine, gives you longer time to connect all the white dots, or just go for trying to fill in the whole globe "both" of them. Stopping the rotation is useful for trying to fill in the blank spots.

This reply was deleted.

IRIS

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