Cats92 - There is a big air gap between that lower plate and the Hoverfly board with lots of air blowing through it. I can't imagine your Lipo changes the temperature of the board at all. It's certainly not a problem.
My current 20C batteries get somewhat warm after 10-12 minutes of flying. I am pretty sure they are also causing me grief when flying. I get these occasionally "cut outs" where all the motors stop for a fraction of a second and then come back. I think it's the ESC's doing their battery protection thing when the batteries drop voltage a bit when I overdraw from them. I've ordered some higher C ones, and should have them soon. I'm giving the Turnigy Nano Tech ones a shot.
@Roy I also ordered a couple of those batteries and have the same problem with them.
@Cats92 currently I am using a 4000mah 30C battery and it just gets a little warm.
If you're flying for 12 minutes, that's only a 5C draw on the pack, on average. Do the dropouts happen toward the end of your flight? Do you know what your pack voltage is when you're done? If it's below 10v you could be hurting the pack - it shouldn't go below 9v under load.
My flights are not a continuous 10-12 minutes. I'm still a pretty bad pilot. Usually, for me, the "cut outs" seem to be mainly when I am throttling up, but it's not every time. Also, I've had some early and some late, but it is more often late (when the battery is nearing the end of it's charge). I do have a little monitor thing that shows the temp and voltage, and has an alarm for when the voltage gets to a threshold (that may be set too low based on you saying it should be 10v, I think it's set to 9v or so). I don't hear that alarm sound when I get the cut outs.
One thing that may be a factor. When I programmed my ESCs I left the battery type set to LiPo based on what Kevin & Nick said at Parallax. The Hoverfly docs say you should set it to NiMh. I'm guessing that this setting in the ESCs is for adjusting it's battery protection stuff. I can try changing that to NiMh, and see if that changes anything.
@Roy: I'm with you on the bad pilot thing...but getting better. The first few days I practiced, it was a bit windy...the last couple days it has been calm...and I have noticed a big difference in my ability to hold a hover in one spot without wind. I figured with the relatively high disk loading of a quad that it would just shrug off winds. Now if I can master that "reversed controls when flying towards me" thing...
@Anyone: I have twice now had incidents where as soon as I lift off, I get uncommanded (and rapidly accelerating) clockwise yaw. Both times this has been when I just plugged a fresh battery in and start to fly. The first time this happened, I tried disarming, then re-arming...but again, as soon as I lifted off, same yaw issue. The second time this happened, I couldn't get the hoverfly board to disarm. In both cases, unplugging battery and re-plugging fixed the issue. Anyone else seen an issue like this? Maybe a bad gyro init somehow? I'd have thought the gyro gets re-initialized every time it is armed, but maybe not?
@Anyone: I have twice now had incidents where as soon as I lift off, I get uncommanded (and rapidly accelerating) clockwise yaw. Both times this has been when I just plugged a fresh battery in and start to fly. The first time this happened, I tried disarming, then re-arming...but again, as soon as I lifted off, same yaw issue. The second time this happened, I couldn't get the hoverfly board to disarm. In both cases, unplugging battery and re-plugging fixed the issue. Anyone else seen an issue like this? Maybe a bad gyro init somehow? I'd have thought the gyro gets re-initialized every time it is armed, but maybe not?
I believe that Tiger may have experienced the exact situation you described. I'll ask him to read your post and make a comment.
@BR - We have noticed yaw rotation issues, only when the the propellers were not placed in the proper CW and CCW configuration. Check HoverFly's diagram #4.10.3 on page 44 and make sure you are matching up CW and CCW rotations per that image.
@BR - We have noticed yaw rotation issues, only when the the propellers were not placed in the proper CW and CCW configuration. Check HoverFly's diagram #4.10.3 on page 44 and make sure you are matching up CW and CCW rotations per that image.
Kevin, did you read how he unplugged the power supply and then everything worked fine? Sounds like his ELEV-8 is properly set up already.
I had that happen the very first time I plugged in the HoverFly board, and thought I had the prop rotations backward. I unplugged the battery and headed upstairs to change them all, but they were all correct. I plugged it back in and everything was fine. I haven't had a problem since.
I know that the landing gear on this allows for a decent amount of yaw wobble - I can see it in my groundstation app. The landing gear mounts in such a way that it can be bent in the direction of yaw very easily. If you bump the quad, even though it looks still it can have a measurable amount of yaw oscillation for a few seconds after it is visibly still. If you set it down then immediately arm it, I'd guess that the arming period is where they take their zero measurement (I do the same). If it was still wobbling during that time, it would think "zero" yaw wasn't zero at all, but the roll & pitch would be fine because they don't have this issue.
Suspecting that this was a possibility, I now wait about 5 seconds before arming the quad after I last touch it, and I haven't seen the issue again.
I also think their gyro zero only happens once - if I remember right, subsequent armings seem to happen much faster than the first one, which would explain why powering down and back up again would fix it. I re-zero mine every time because it helps compensate for temperature drift if you haven't calibrated.
I made it to the park today and have some video of my Elev-8 w/ the Hoverfly sport board running JasonDories code. I am a beginner flyer and I did not do any loop de loops but I also didn't crash once w/ Jason's code!
I had a problem with failure to disarm recently when I failed to notice that a couple screws fell out. I had quite a bit of vibration and when I would spin it up for testing and then bring it back down, it would not disarm. The only thing I could do to reset it was disconnect the battery. My conclusion was that there is something in the software that crashes when there is excessive vibration. The problem was easy to duplicate. I never had a disarming issue before this and have never had it since. I think if I had the problem again and couldn't find a mechanical issue with the quad, I'd start looking at blade balance or a bent shaft.
While we're on the topic... I think a number of people have had a problem with the screws vibrating out of the nylon standoffs on the motor mounts. Because they are nylon, you can't loctite them so I would highly recommend installing external tooth (star) lock washers on all of those standoff screws. (Do not use split or internal lock washers) An even better solution would be to replace the standoffs with aluminum and use the loctite. The difference in weight is insignificant and the consequeces of failure could be huge. Personally, I think this is something that requires immediate attention, because it's just a matter of time until you have the problem. If you are in the air when it happens, the lock washers or new standoffs are going to be a lot more expensive.
Do you have a screw loose? I have your solution...
I will send out a free set of star lock washers to anyone that has bought an ELEV-8; please email me with your full name or customer number so I can send them to you.
The problem has been noted and we will be adding the lock washers to future kit builds.
David that is the one I use. I like it because it charges LiPo, LiFe, LiLo, NiMh, Pb(lead acid) and NiCads.It also power charges while it balance charges. You can also program the charge amp rate and it displays the current charge amps, battery voltage and can show the current individual voltages of each cell. It also operates off A/C or D/C. Here is a pix of it's setup recharging my battery this morning.
David that is the one I use. I like it because it charges LiPo, LiFe, LiLo, NiMh, Pb(lead acid) and NiCads.It also power charges while it balance charges. You can also program the charge amp rate and it displays the current charge amps, battery voltage and can show the current individual voltages of each cell. It also operates off A/C or D/C. Here is a pix of it's setup recharging my battery this morning.
Thanks for the information! I just ordered one along with a couple of batteries. When all of this stuff comes I should have everything I need to get my ELEV-8 flying!
@Ken in post#307 you showed an open board. I plan to use Jason's code that's he is developing in the projects-forum for my Elev-8 and would prefer not to solder up a Prop proto-board to add the receiver/ESC interfaces and gyro/accelerometer. The open board would make this so much easier. Is Parallax still going to offer this and if so can you give us an approximate time frame?
Edit: Will unused Propeller port pins be accessible on the open board?
Edit2: If the open board has an ITG-3200 gyro on it already and if the receiver/ESC's/gyro interfaces are aligned w/ the Hoverfly-sport board then Jason's code he posted in this thread will operate the open board.
D-Rat - I plan to make whatever changes (if any) are required to support the Open board when it becomes available, assuming it's not just pin-compatible to begin with.
Also, I watched the videos - looks nice & stable. (phew)
Jason that's great. I was dreading soldering in all the plugs for the receiver/ESC's on a Prop proto-board. Still wondering if Ken has any kind of time frame for availabilty of the Open board?
Evil Ken? As opposed to Good Ken? Thanks for the feedback Jim. Actually I don't/won't have the hardware. But I will find other projects. Not sure there's enough time to come up with something new and finish it for the Expo, but we'll see.
So Ken's been twisting my arm a little and I've agreed to make a few more of the anti-vibration standoffs. Since making more of them on the manual lathe would really be a lot of work, I'm switching over to a Haas CNC. Because you can do things on the CNC that would be impossible manually, I've redesigned the standoff a bit. Now it's more like I would have done it as a production part. I''ve rounded some of the sharp corners with a .005" radius and stuff like that. I've also switched to hex standoffs so you can use a wrench to tighten the screws (don't forget loctite). I could have used bar stock in the CNC to make the whole thing, but using the standoffs makes it a little faster for a short run. I'm not sure how many I'm going to make, but the plan is to make enough for all the current forum dwellers. This is a one time run so when these are gone it's over.. I hope to send whatever I make to Ken on Monday and you guys can get them from him.
I got the CAD design done last night and got most of the program written. The standoffs came on Fed-X today so I thought I was ready to go. Tonight I was going to make some samples and came to the realization that I didn't have or at least couldn't find a collet to hold the 1/4" hex stock. I really needed to get these off my plate this weekend so I decided to try making my own hex collet from a brass emergency collet. The first problem I ran into was that I didn't have a really small end mill with a long enough reach (3/8"). Tiny end mills are always short. What I ended up trying was a 2mm carbide burr designed for pcb routing. I was afraid it would load up with the brass so I cut .010" depths at 6000 rpm, blew air on it the entire time, and cut really slow. It took 20 minutes to make the hole, but it worked great. So tomorrow the plan is to start making standoffs. I'm attaching pics for you CNC minded guys that might want to see how well it turned out.
Great job. I really like the extra hex area for tightening. And thanks for the details on what you are doing. Now everybody should know why the are called "emergency" collets.
Good Ken - Could I please be added to list to get a set of these? Thank you.
HOW TO REQUEST THE ANTI-VIBRATION STANDOFFS PRODUCED BY FORUM MEMBER TIGER
Many thanks to Tiger for putting his CNC lathe to work for the benefit of ELEV-8ers everywhere. This kind of community collaboration is really what we hoped for with this project - the contributions, modifications and solutions presented here have been very valuable to the community! Here's how you can get a set of Tiger's Anti-Vibration Standoffs for your ELEV-8:
Limit one (1) set per customer.
Send an e-mail to Julia, my professional assistant at jquillen@parallax.com. Be sure to thank her, too.
Provide your shipping address.
They will be sent to you via USPS, no tracking.
Julia will let me know when our supply of Tiger's Anti-Vibration Standoffs have been exhausted.
I finally had some free time to work on my Elev8 build today.
A few frustrations so far (not enough 1" screws, for example). My biggest problem at the moment is that the three wire plugs don't fit my AR8000 receiver. They are just a smidge wider than a normal servo plug and the AR8000 is quite rigid on that. Has anyone successfully mated them?
Comments
...Tiger
@Cats92 currently I am using a 4000mah 30C battery and it just gets a little warm.
http://www.hobbypartz.com/77p-sl4400-3s1p-30c-3333.html
One thing that may be a factor. When I programmed my ESCs I left the battery type set to LiPo based on what Kevin & Nick said at Parallax. The Hoverfly docs say you should set it to NiMh. I'm guessing that this setting in the ESCs is for adjusting it's battery protection stuff. I can try changing that to NiMh, and see if that changes anything.
Also, my current batteries are 3000mAh 20C.
@Anyone: I have twice now had incidents where as soon as I lift off, I get uncommanded (and rapidly accelerating) clockwise yaw. Both times this has been when I just plugged a fresh battery in and start to fly. The first time this happened, I tried disarming, then re-arming...but again, as soon as I lifted off, same yaw issue. The second time this happened, I couldn't get the hoverfly board to disarm. In both cases, unplugging battery and re-plugging fixed the issue. Anyone else seen an issue like this? Maybe a bad gyro init somehow? I'd have thought the gyro gets re-initialized every time it is armed, but maybe not?
I believe that Tiger may have experienced the exact situation you described. I'll ask him to read your post and make a comment.
Ken Gracey
Kevin, did you read how he unplugged the power supply and then everything worked fine? Sounds like his ELEV-8 is properly set up already.
I know that the landing gear on this allows for a decent amount of yaw wobble - I can see it in my groundstation app. The landing gear mounts in such a way that it can be bent in the direction of yaw very easily. If you bump the quad, even though it looks still it can have a measurable amount of yaw oscillation for a few seconds after it is visibly still. If you set it down then immediately arm it, I'd guess that the arming period is where they take their zero measurement (I do the same). If it was still wobbling during that time, it would think "zero" yaw wasn't zero at all, but the roll & pitch would be fine because they don't have this issue.
Suspecting that this was a possibility, I now wait about 5 seconds before arming the quad after I last touch it, and I haven't seen the issue again.
I also think their gyro zero only happens once - if I remember right, subsequent armings seem to happen much faster than the first one, which would explain why powering down and back up again would fix it. I re-zero mine every time because it helps compensate for temperature drift if you haven't calibrated.
video1
video2
While we're on the topic... I think a number of people have had a problem with the screws vibrating out of the nylon standoffs on the motor mounts. Because they are nylon, you can't loctite them so I would highly recommend installing external tooth (star) lock washers on all of those standoff screws. (Do not use split or internal lock washers) An even better solution would be to replace the standoffs with aluminum and use the loctite. The difference in weight is insignificant and the consequeces of failure could be huge. Personally, I think this is something that requires immediate attention, because it's just a matter of time until you have the problem. If you are in the air when it happens, the lock washers or new standoffs are going to be a lot more expensive.
...Tiger
I will send out a free set of star lock washers to anyone that has bought an ELEV-8; please email me with your full name or customer number so I can send them to you.
The problem has been noted and we will be adding the lock washers to future kit builds.
Thanks for the battery recommendation. What charger do you use? Would this one work okay?
http://www.hobbypartz.com/thac6smbachw.html
Thanks,
David
Edit: Will unused Propeller port pins be accessible on the open board?
Edit2: If the open board has an ITG-3200 gyro on it already and if the receiver/ESC's/gyro interfaces are aligned w/ the Hoverfly-sport board then Jason's code he posted in this thread will operate the open board.
Also, I watched the videos - looks nice & stable. (phew)
To those who have been asking my progress on this, I apologize. I guess I will not be doing the demo as planned. :frown:
Sounds like evil Ken has you working on other work related projects.
Press on.. We will be happy with what you come up with and look forward to your next posts on the other projects..
Jim
I got the CAD design done last night and got most of the program written. The standoffs came on Fed-X today so I thought I was ready to go. Tonight I was going to make some samples and came to the realization that I didn't have or at least couldn't find a collet to hold the 1/4" hex stock. I really needed to get these off my plate this weekend so I decided to try making my own hex collet from a brass emergency collet. The first problem I ran into was that I didn't have a really small end mill with a long enough reach (3/8"). Tiny end mills are always short. What I ended up trying was a 2mm carbide burr designed for pcb routing. I was afraid it would load up with the brass so I cut .010" depths at 6000 rpm, blew air on it the entire time, and cut really slow. It took 20 minutes to make the hole, but it worked great. So tomorrow the plan is to start making standoffs. I'm attaching pics for you CNC minded guys that might want to see how well it turned out.
The things we do and call it fun! ...Tiger
Great job. I really like the extra hex area for tightening. And thanks for the details on what you are doing. Now everybody should know why the are called "emergency" collets.
Good Ken - Could I please be added to list to get a set of these? Thank you.
Al
Many thanks to Tiger for putting his CNC lathe to work for the benefit of ELEV-8ers everywhere. This kind of community collaboration is really what we hoped for with this project - the contributions, modifications and solutions presented here have been very valuable to the community! Here's how you can get a set of Tiger's Anti-Vibration Standoffs for your ELEV-8:
- Limit one (1) set per customer.
- Send an e-mail to Julia, my professional assistant at jquillen@parallax.com. Be sure to thank her, too.
- Provide your shipping address.
- They will be sent to you via USPS, no tracking.
Julia will let me know when our supply of Tiger's Anti-Vibration Standoffs have been exhausted.We are pleased to help make this project happen.
Sincerely,
Ken Gracey
Joss, are you referring to Kevin Cook of Parallax? If so, it's kcook@parallax.com.
Ken Gracey
A few frustrations so far (not enough 1" screws, for example). My biggest problem at the moment is that the three wire plugs don't fit my AR8000 receiver. They are just a smidge wider than a normal servo plug and the AR8000 is quite rigid on that. Has anyone successfully mated them?