Another thread for future reference for anyone else having this problem. I've searched the forums here and ardupilot.com with no success in finding an answer.
I have the 2014 Y6B RTF kit that was assembled and "tested" before shipping by 3D Robotics. We paid for the extra Telemetry and FPV/OSD options primarily to track on-board battery voltage and other crucial vehicle stats. Since day-one taking this unit out of the box, the Mavlink telemetry has shown 0.0 volts, and the OSD display shows a Full Battery icon on the left side of the screen.
Today it crash-landed, breaking the GPS antenna mast and a piece off of one of the landing legs because the battery voltage got too low I assume. I was pushing the battery for the first time since we got it, and never got any warning that I'm aware of before it dropped like a rock onto pavement with almost no power. Luckily it was only about 20 feet up and tumbled onto its top.
I have a help request in to 3DR to see if they have any advice. I will post up what I hear back. If anyone else has any suggestions, I'm open to them. The kit did not include the OSD programming cable, that has to be purchased separately from 3DR, which I plan to do soon.
Below are screen shots of the Telemetry and OSD display.
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http://www.ebay.com/bhp/lipo-alarm
Also, it helps to get a feel for how long you can fly and then set a timer to warn when you get close. My transmitter has a timer countdown for when the throttle is over 20%.
We got our 3DR Y6 last week. It was supposed to be RTF. The Pixhawk's settings were left at default and never programmed for the Y6, as best we can figure with 3DR's help. Our story is pretty much the same as yours. The battery monitor was disabled. Here is how I set it up:
First, measure the voltage from your main 6000MaH battery, write it down, then plug it in and connect via Mision Planner (or similar software, I suppose).
In MIssion Planner, you will need to go to the battery monitor settings in Initial Setup>Optional Hardware>Battery Monitor. The settings I am using are the following:
Monitor: 4 Voltage and Current
Battery Capcity: 6000MaH
Sensor: 0: Other
"check" MP Alert on Low Battery
APM Version: 4: Pixhawk
Measured Voltage: For this field in the table, you need to measure the voltage of your battery at any given moment, type in the voltage value, and then plug it in. That calibrates the voltage reading.
Next you need to go to the Initial Setup>Mandatory Hardware>FailSafe screen. In the "FailSafe Options box to the right, I've got the Battery FailSafe box checked, Low Battery set to 14.0v, and reserved mAH set to 1000mAH. (This assumes you have a 4S 6000mAH battery like I do).
Those are just my settings based on some reading over the weekend. 3DR agreed on the 14.0v, and points out the battery might be damaged if it goes much below that. I've read 3.3v per cell, or 13.2v is the actual point at which you worry about damage, but it has to have some power to execute a RTL, so 14.0 seems safe.
3DR has been very supportive, and they are working with me on getting the damage fixed from my 100m fall onto a concrete sidewalk. I'm actually amazed how little damage was done. The legs got bent and some of the plastic rods between legs cracked. Like yours, my GPS mast crumbled and the support plate it mounts to broke off, as well. The frame and electronics appear to be fine. Pretty tough machine. Now that it appears to be set up correctly, it is doing better.
Thanks again for the thorough walkthrough. After doing all that, I do get a battery indication of "99%", but it says 13.5v instead of the measured 16.8 I entered. Is that normal?
*EDIT* Ok using a different software, APM Mission Planner 2, I was able to get it to show the correct voltage by entering the same "16.8" value in the Measured Voltage field and pressing enter. For some reason Mission Planner software was not updating the Pixhawk firmware properly, and showing a low voltage or 0.0v reading when I tried to enter a value a second time.
And now the OSD shows proper voltage and battery level also. WOOT WOOT!
If there are any other default settings that need to be programmed for the Y6 RTF kit, let us know.
Thank you Haygood, sounds like exactly what I need to do, and I'm about to get on it also.
I too was amazed it wasn't damaged more. I could have swore I saw the blades disintegrate, but even those were just a little scratched up but fine. I have some 11x4.7 blades coming in today at my LHS anyway, so those are going on. The only other "damage" was one of the CF plates in the legs popped out...went back in easily after loosening the attachment bolts.
One mod I did that helped some is dipping the tips of the landing legs in a couple of coats of PlastiDip. I mostly did this to protect the carbon fiber from getting scuffed up from landings over time, but watching the video I noticed it "touched down" while moving sideways at a pretty good rate, and skidded for a second on the PlastiDip tips before catching and flipping over. I'm pretty certain had the legs been raw CF with those sharp edges, it would have immediately grabbed hard, possibly breaking more on the legs, and slamming over harder onto the blades.
I also have an idea for making the replacement GPS mast I get more of a "Break Away" design. I'm going to cut the CF pole in two down about 1cm above the plate, then use silicone fuel tubbing to attach the pieces together, or maybe just electrical tape. If it works like I think it will, the mast pole will separate right there at the cut in a crash before doing damage to the mount plate swivel thingy, but still be rigid enough to put up and down without separating.
While the Y6 might be RTF, you still have to configure the software yourself. Have you tried setting up the battery monitor in Mission Planner? (it is under Optional Hardware). http://copter.ardupilot.com/wiki/common-measuring-battery-voltage-a...
Understood, I'll give that a go tomorrow, thank you Spencer.