First this IS NOT a bashing session this is a search for answers and opinions so try to be respectful and courteous !
me personally i think the APM is capable of bringing my plane back and landing if the rx fell out ! do i think DIY should be responsible to implement it ? no but they are flying too so if we come up with a good proposal i,m sure they would try to make it happen !
this discussion is intended to come up with scenarios where your platform would go out of control ! and what we can do ! there should be a sister post Mitigating the chances of losing control .
i,ll start out . with Geofencing(here after to be referred to as GF) turned on i can't see how your platform can fly away so maybe GF should be turned on from default with a tiny box that you have to adjust to your area,platform,and conditions ? but not all of us carry a laptop to the field so maybe we should be able to save it and recall a few different versions for different fields and or conditions that way you could program it at home and go fly , but if you turn it on to far away from the place you selected as home it should lock up and beep or flash an error that way it wont try to fly 40mls back to your house (00) a safe configurable selectable autoland function tied too GF would be nice too.
at least this would protect the DIY community from litigation and put responsibility on the user and would save a newbie from a painful costly learning experience !!! feel free to poke holes in my ideas !
Questions leads to answers and isn't it wonderful we need not wait another second to make the APM better and if we do a good enough job maybe the government will force the AMA to use our product on all there large dangerous aircraft ! and would help in the UAV community acceptance into the sport
now have at it
Thank you both! I will get some parts on order and a fail safe set up as soon as HK can get me the parts. It seems like lately there is a lot of bitching on this site but I for one love it and have had a blast learning thanks to all of the helpful members of this community!
Note that if you want CPPM, that Rx will need a firmware update. To do that you will need this:
And maybe this, I needed it for my older Rx, but apparently the new ones don't? I'm not positive:
This Rx does it stock:
And this one does put 8 ch CPPM out even though its a 4 ch. Great option for little aircraft, though I'm not sure if it's reduced range or not.
And get some of these:
This allows you to have voltage feedback, plug right into the Rx, and don't need the sensor hub.
And you may want a screen rather than just a beeper in the module to warn you.
You could also go this way. Buy this one instead of the DJT module, it is the screen, and the Tx module in a single unit, and then also get the little 4 ch Rx. Requires some minor hacking I believe.
Sorry but what is CPPM?
Jason, basically, your Tx takes all the commands on all 8 or whatever channel, and combines them into a single signal. 8 pulses of measured width, simply put. The Rx takes the pulsetrain, and chops it up into the 8 pulses for the servos, and sends it out on each servo channel. Then you run all the wires from the Rx to the APM, and, unbelievably, the PPM encoder assembles them back into a 8 pulse train, and sends that to the 2560 chip.
CPPM is that 8 pulse signal all together. So basically, the Rx passes is on to the APM directly, instead of it getting chopped up and reassembled again. I think it's just better in every way. It's cleaner, simpler, and less places for things to go wrong.
Ok that makes since. One more question if you don't mind, If I update the firmware am I back to ground zero setting up the radio? I only ask because setting up the mode switches kicked my butt!
Thanks again for your help!
I don't think you need to upgrade the firmware in the user side of the Tx. I don't even think you need to upgrade the firmware in the Tx module. It's only the Rx, and that doesn't do anything to the radio settings. I didn't even have the rebind, which surprised me.
Overall, the change was fairly straight forward once I figured out which instructions I needed to follow. But if you buy the DR8SP or the 4 Channel, you don't need to do anything to the firmware. It's only if you have a non-CPPM Rx, you need to flash the firmware.
I did have to de-case the Rx to flash it, which voids the warranty, blah blah blah. Like I'd ever warranty a $20 Rx I bought from China.
This is just my opinion and thus take it on face value, I would not and will not fly with a 9x.
You've done the smart thing and upgraded to a FrySky module, but that doesn't solve the fact the very potentiometers attached to the sticks won't crap out. Talk about serious potential to loose control. My luck would be the throttle channel since it get's used the most.
Here's my logic, a radio that costs less than $150 had to cut corners. You fly an aircraft with at least $600 in components in it. Is it really worth saving a few bucks to crash the crap out of the very expensive $200 APM? Almost every APM involved in a crash has some level of damage. It only takes once. I say this VS I spent $400 on a DX8 Spektrum, got 2 each AR8000 receivers (thus one radio and receivers to cover 2 aircraft) then bought an Orange Box DSM2 receiver that actually works very well. To me, not having the problems that have now swamped several threads with functioning failsafe seems worth it. Not to mention I at least feel like I may not have to use conductive paint to fix my radio. I'm not saying a Spektrum is perfect, but I felt like I get my value out of it in tested and proven performance.
Thanks Lefebvre, that indicates that the APM itself is absolutely fine.
It detects loss-of-control-signal and activates the chosen behaviour. This is good.
The PPM Encoder is faulty, because it does not pass on a loss of the Throttle (failsafe trigger) channel to the APM.
The PPM Encoder should be changed so that a missing Throttle channel is always passed on to the APM as throttle at 900us, thus triggering the APM failsafe behaviour.
If the PPM Encoder did not hide a loss of throttle channel from the APM then there would be no issue with using the 'stock' 9x receiver because it would work as Turnigy intended it to.
End of story - the PPM Encoder is broken by design and needs to be fixed.
Please treat this as a formal bugfix request.
Richard, I don't disagree that some people may want the functionality you describe. You should go ahead and write an Issue for this feature, and maybe a Dev will work on it. Or, you or anybody else can do it, and distribute the code. That's the beauty of open-source, you can do anything you want.
That's fine. But we're coming to the crux of this WHOLE issue here.
This is an open source project. You, and many others are benefiting from the work of volunteers. If the software wasn't free, you'd be paying A LOT more money for this system. The developers work on what they are interested in working on. Simple as that.
You have no right to come in here and DEMAND that changes be made, which is what you have done. That is the reason this whole thing has gone the way it has. And the idea that we are liable for accidents that befall you due your 3rd party equipment choices, or your decision of operating location, your choice to not purchase affordable insurance that require you to operate under a set of reasonable guidelines, is extremely offensive.
Simply put, if you are happy with the way this works, you are perfectly happy to buy another system. If you had approached this in a more reasonable way, things would have probably worked out differently.
Thankyou, I had not found that issue report yet.
Interesting discussion. Still reading all the comments as we're looking into failsafe techniques for our unique flight conditions.
One common thing is present: if you lose supervisory control, hold position, verify and correct your heading (so [you] it knows what to do next). For planes it's tight circles, everything else, just stop and hold. All other startegies (GF, RTL, Land, Lift, etc..) are context sensitive (e.g. don't want to RTL in a middle of others flying around). Achieving that one mode: then there are many ways on how the APM can get your vehicle back safely.
Also by example: 9 out of 10 robots (from Willow Garage's to iRobot's) trigger an e-stop, or "motor-power-off" on a failsafe event, newer units are starting to hold position (i.e. vamp).