Psyborgs Gremlin Build Setup and Review

[PsyBorg]

Ok to start I will say I am sorry for not documenting this from the start. I was all excited to be able to rearrange some grocery money last month and this month to scavenge up enough to snag a kit while they were in stock. No Psyborg is not starving (yet) as try to keep a decent stock of food so no worries.

So as you know from other threads that I and many others went thru a nightmare with getting drivers straightened out to be able to even start a build. In fact some are still fighting that monster. To them I will say Walk away. grab something to snack on, take a deep breath and start over.

I know all the documentation tells you what drivers to load and several people have even posted other options with 3rd party driver management. What worked for me was this... I uninstalled all the normal drivers associated with multi rotors and flashing them. I did a cold boot as a normal restart with windows will only make windows think it needs to reload the drivers that still remain on the start up list. SHUT OFF YOUR MACHINE.

Once that is done I restarted and ran a reg cleaner to make sure there were no orphaned entries or strings. I then started Zadig. Now..All the docs say that win drivers are the ones. For my case They never worked. I selected each one after the previous process until I found the libusb one actually let me access DFU mode in zadig. It was at that point I could follow the normal flash procedure and move forward.

Over the three or four days it took to sort that mess out I had already completed the build as I needed something to distract me from the driver issues. This is what mine looks like now on the Josh B Delrin frame. Notice I did an over and under motor configuration using longer stand offs. I had planned this to get the props in a straighter line but also was hoping to put the battery in the center to keep the weight on that same axis since these are so tiny. Sadly the batteries I have on hand from myy old 200 size heli that never flew are just a touch to big to fit in there. I will leave this set up for now as in the future I hope to have batteries more suited for this quad size. I know these pics are also in another thread but this will consoldate everything JUST for the Gremlin build.















Here is a video of the final build after all the changes and adaptations I have done to make it fly and function so far. More to come in the next entries.

 

[PsyBorg]

I was so psyched once I had completed the build. I think it turned out reasonably neat and clean considering how small everything is to work on between not so great eye sight and incredibly twitchy hands when trying to work on something thru granny glasses AND a lighted magnifying glass.

Here is the very first lift off using stock pids in Betaflight.

Here is what I ended up with after a few tuning hops before the battery ran low and it was time for some sleep. These were the numbers and then the video is the hover test. Still had some wobbles but that was in a small hallway with only 20 on I terms and 10 on D. Not too bad with all that rotor wash and turbulent air.

I will say now to let you guys know. When you tune these things I would say cut the stock P gains in half for pitch and roll and drop yaw by at least 30% to start. I messed around and went higher as well as lower on my first outside flights using separate profiles so I could just change at will to make it easier.

Here is what I had at the end of the first day flying outside. THIS is where you find out how bad this Hyperion Camera set up is tuned. First thing you have to do is carefully peel the half a bottle of glue off the threads and HOPE you can do this without damaging the camera or the lens mount itself. I think the guy at the factory responsible to do this has got to be half blind and very shaky to be this far off with a static focus. Anyway here is the first video outside AFTER reworking the focus best I could without doing damage.

That video was edited in You tube to bring up the brightness and contrast because there were sections of the flight in raw format you could not see what was in front of the quad. The base contrast setting is too high and the brightness is way to low and the fact it takes forever to adjust from the light to dark change it more then likely will be the cause of more then a few crashes. I even had the goggles cranked up in the hazy afternoon light that things were looking washed out in the brighter areas to help the video recording.

The final straw on the camera is the CP antenna. It is too thin and the first time you land on it you will pancake it. I had rebent mine at least 5 times on the first day. Litterbug suggested to go to a dipole by removing an already tuned dipole out of the casing of them freebie antennas that come with everything. I did just that as you can see in the final build video in the previous post.

This ends day one. More in the next post.

 

[PsyBorg]

On to today's flights and testing.

I completed the antenna swap last night and charged batteries for a fresh start today. I did initial testing and found that if I used race band channel seven I could set up my Alien and the Gremlin as well as use the monitor I have because channel seven carries over into a different band.

It all looked good on paper and in static tests last evening. Not so much in the field. I was getting really bad break ups the first two flights that were far too long to re establish good feed to fly with. So I started the day frequency hopping. I lucked out as I remembered that I was flying the A band channel 7 with the Runner 250 when I first started as well as the Versa copter so I tried that and it seemed happy. Some static but very flyable. I will play with channels more over time for this one.

Here are the pids I was using today. The next step is to change the TPA a bit to see if I can ease some of the higher throttle oscillations before I start messing with things like filters and such I know nothing about. I think this is the one that flew most stable as I had three profiles set up to test today.



I have two separate videos but its of one flight. When I bounced the end of the first one the video recording started a new session. I somehow managed to miss the timer alarm and ended up flying the pack flat. I just put it on charge after the other two so it could have time to recover and all cells started above 3.5v so no damage. Here are the two flights to finish out the day.

On this first video I have changed the lighting so you can see better. The second half of the flight I will leave raw to give you a comparison.

Summary:

Over all I like the Josh B version of the Gremlin. I liked Alex's Alien copy but that was not a choice and this frame is kind of unique. TJ's would have been my second choice until I saw how much of the rotor blades were in the FPV view. Far too intrusive for my old eyes to see around.

So far this thing is a beast. I am flying a battery that weighs nearly as much as the quad itself. Current weights are 88.1 for the final build including the rubber band because the supplied O ring is too small for the batteries I have. The all up weight I am flying is 160 grams. I know that is very heavy for a build this size and over time I will acquire more suitable batteries.

I still have a ways to go on the tune as again this is a learning process as I have never worked with something this small and I have never messed with Beta flight with all the fancy filters and tuning. Currently I am flying One shot 125 but I would like to fly using Dshot. I had originally set it up for Dshot but for some reason one motor would not spin up. I will be looking into flashing the esc's now that I am fully functional and then see if that gets me where I want to be.

Even in its heavy imperfect state you can see what this this is capable of and I think over time with a better camera it will be that much more enjoyable. It punches out in proportion to its size vs my Alien feel and is just as maneuverable using the same rates just a little more expo

Finally I may end up slotting the frame in the front so I can get more camera tilt as the tiny bit I have now is messing me up with coming out of stunts as I end up stalling or even moving backwards after I finish a trick.

I hope all my blathering has shed some light on the Gremlin as well as pointed to a few areas that could use some love to help people make choices for a better out of the gate experience. Good luck on your builds and happy flying.

 

[PsyBorg]

I was able to recharge two packs while I was posting and got back out before the sun went down. I raised TPA from .10 to .25 and that was the sauce!! Soooo much smoother. I think I will lower it from 1650 to 1500 and maybe bump it to .27 or .28 for tomorrows runs or whenever weather allows. The video is far too dark to post but wow what a difference on punch outs and near full speed runs. Camera tilt has just become a must in the loop to happiness. You guys may want to start at that .25 before trying to dial yours in to make it an easier experience.

 

[HughHemington]

I see you're using an S3 LIPO and connecting to the balance lead with a JST. Are you tapping the last balance lead (3-cells) or the next to last?

 

[PsyBorg]

I am using all 3 cells and removed the inner two pins on my adapter so there was no possible way of shorting the battery. I do NOT advise flying like this as those balance wires are not meant to carry current. This is only temporary until I can acquire the correct batteries with the correct connectors.

BTW I saw your comments on my videos and replied there as well to your other questions.

 

[PsyBorg]

Sooo.. was a bright sunny day so I decided to walk back up to the park and try to fly the few trees I saw yesterday that had gaps perfect for the Gremlin.

I learned two things. First the Gremlins CAN fly in over 20 mph gusts... They are not happy but they can do it. Wasn't able to hit the gaps when those gusts kicked up though was flying strictly open field LOS for me.

I had to fly LOS today because the Hyperion Camera I have is not flyable for me at all. I am not sure if I got a Monday or Friday model like the union cars that have all the problems because they were Monday or Friday cars. I am not sure if Chen the focuser and tester had a REALLY bad day. All I know is the way this thing handles light makes it the worst product I have bought in my quad copter span of building and flying. I thought it was bad on over cast days. Its even worse on bright sunny days. I could NOT for the life of me find a balance between contrast and brightness on my goggles where I was not ether blinded by the bright wash out of everything or nearly in total darkness. Seriously I did the settings in the sun and the simple change IN the open sun light of turning to have the sun on one side or other was such an extreme change when facing into or away I got blind either by light or dark.

So that all said I really hope you guys make out better with these cameras as I can not fly like this and will have to set the Gremlin aside til I can get a functional replacement.

 

[Michael9865]

Do you think something like this would work better for the camera?
https://www.banggood.com/Super-Mini...-p-1095683.html?rmmds=detail-left-hotproducts

Is there a way to toggle off the FPV transmitter on the original setup for when you want to fly LOS? Thank you, in advance.

 

[PsyBorg]

Hello Michael

Sadly no. That camera may or may not be any better. You roll the dice with low price "get it out the door gear" from China. I think atm the only tune-able cameras are ccd not cmos and I think they are still the standard size board cameras. The Gremlin will easily carry one and I will probably use my old 25 mw vtx and get another CCD camera or try the one off my Versacopter first.

As far as Banggood I will not even discuss them as they merely resell stuff that was stolen and poorly copied from other companies. More so now that they sell FT knock offs. I know most of the gear we get is made there but I would rather support a more local source because one they will back the products in most cases and two it does not take half a summer or more to get the parts you ordered.

Some of the newer full size flight controllers may be able to but not any micro I have seen yet. You can get a digital switch and connect it to a channel on your TX though. You could also get a micro switch and manually toggle power when you want to have longer battery life. OR you could just put a connector in the power line to the camera set up and simply unplug it or even use pins and connect that way.

 

[cranialrectosis]

Glad to see you got it going. Those drivers are a real PITA!

What's up with the camera? Is it blurry and unfocused or can you not change it to handle different light or is it that the VTX signal is not very good and you get a lot of white noise in the video?

 

[LitterBug]

I am going to be switching up the FPV gear on my micro. The Pico-AIO cameras are OK for indoor flying just for fun, but outdoors, they can be a mixed bag of fail. The lens is usually uber wide angle, and the CMOS camera has no adjustability for different lighting conditions. I've had best results using the RMRC Cricket Cam V2 AIO camera/VTXes. They come with dipole or CP https://www.readymaderc.com/store/index.php?main_page=product_info&cPath=11_62_625&products_id=6563

I picked up one of these FXT sets https://www.readymaderc.com/store/index.php?main_page=product_info&cPath=11_62_625&products_id=6327 recently but have not mounted it up yet. At least with these, it will be easier to try a different camera such as https://www.readymaderc.com/store/index.php?main_page=product_info&cPath=11_62_625&products_id=5705 .

Been busy with family stuff lately and haven't been able to give them any real testing. Still need to replace the 4in1 ESC on my Pico-X frame which will be my test bed.

Cheers!
LitterBug

 

[PsyBorg]

Glad to see you got it going. Those drivers are a real PITA!

What's up with the camera? Is it blurry and unfocused or can you not change it to handle different light or is it that the VTX signal is not very good and you get a lot of white noise in the video?

Its all of the above mate.

It came unfocused with enough glue on the lens to tie down a jet to an aircraft carrier in a hurricane. Once I dug as much of the glue off with an xacto blade as I could I managed to get a better focus but not perfect as I did not want to damage the lens or the mount.

Then when I flew it the first day in over cast clouds it was not so bad and flashy contrast wise but the antenna on it was all white noise and had drop outs. After flying as hard as I do It had been smooshed up enough I knew it would not last and that's when I did what LB suggested and change to a dipole. It got better but still is weak and staticy. The nightmare comes on bright sunny days and it becomes un flyable. The contrast is so high the clouds shimmer. To me the contrast seems set wayyyy high and brightness way low for fpv. Add in the way it switches from low light to dark light and you end up flying blind most of the time. There is only so much adjustment that can be done with the goggles.

@LB I will look into another camera when I have funds to spare. I think I may experiment and use the original 25 mw tx and the ccd camera I have on my Versacopter. Not happy to be adding even more wight but with summer here and the bright sunshine Its not going to be a happy experience flying as is.

 

[PsyBorg]

Well got some new news on the camera front. Also Bills law recent attack.

I decided to dig out the power filter I was running on the Versacopter and see if that helped the video with this camera. Luck would have it it cleared up the signal enough to actually make it flyable even with the harshness with the contrast. I did it late at night so I could not test fly it though. I did however grab the little monitor as well as the goggles and did some walk around the apartment tests. I went behind walls and doors and into closets and it seemed to penetrate fairly well so I figured in open field it will be OK.

Since the weather was supposed to be good I spent the rest of the night charging batteries while I watched a few movies and played some video games for a bit. I got a short nap in and then walked up to the park I figured I would try the Gremlin out first and then go do a race course on the baseball field after. I set up in the picnic area where there are a few trees with open spots to fly gaps with the Gremlin. there were two boys there and they were hanging out and talking while I was setting up.

I got it all set up and powered up. Took off and did a few quick laps around the trees to check range... STILL crap..but flyable close in by the first few trees. I did a few flips and rolls to see if the signal dropped and it did so there was a flop or two in the grass. Had to do several walks of shame in front of them kids..

Anyway I decided it was time to show off and do a split S over a branch and come back out under a tree. Bills law took over and I over shot the first branch by more then I wanted and as I flipped upside down to come back the other way I guess I face planted on the next branch. Hard to tell cause video went out immediately. On inspection I saw I had managed to do what I predicted and snapped off the tower portion of the pcb where the antenna mounts. That is an engineering feat of pure genius having that stick up like that on something they KNOW will be landed on..... Needless to say the Gremlin was down for the count so I packed up and went to set up the race course. That part of the day went well with only one crash on my gate thru 5 packs I have to fly with.

Anyone that got that Hyperion camera I suggest you hot glue the snot out of that tower to protect it.

Anyway I spent a few hours sanding the edge of that board and carefully uncovering traces to see where the antenna connected. If you think your eyes went buggy soldering the Gremlin wait til you have to repair the camera... long story short (heh that's likely with me huh) I managed to get a functional repair done but I have serious doubts for its longevity. The two connections I managed to make are now wider then the core for the antenna wire so not much there to hold on with. It is covered in hot glue so we shall see how long it holds.

 

[ElectriSean]

Do you know anyone with a 3D printer? Some type of antenna guard like on the Aurora 90 would help protect the weak design of that camera.

 

[cranialrectosis]

Anyone that got that Hyperion camera I suggest you hot glue the snot out of that tower to protect it.

That kinda does look like a phlegmy boog there doesn't it?

Any hope of using an HS1177 or is that just too big?

 

[PsyBorg]

I would love to run an hs 1177 the problem is the wight and room for a separate TX. Although I am over 180 g now with between the heavy batteries and teh added power filter as it is. That is the next phase after this camera dies which I am pretty sure its on its last minutes of life at this point. I will use the one off my Versa with my original 25mw tx. should weigh that set up and see what the difference is. I know I can fly that without a power filter. That camera is not an hs1177 but it is ccd and settable and already pretty much dialed in too.

Dammit Cranial.. now ya got me wanting to try.. Well I have two hours before the rain rolls in here this afternoon so I will go fly with the current set up and if that does bite the dust then this evenings project will be a swap over.

 

[cranialrectosis]

If all else fails, seriously, check out the Alien 4".

 

[PsyBorg]

I will roll with what I got. If I have to the Gremlin will be just an LOS small area flyer / let others get the bug quad. If I get to the point I can isolate funds the next build will be a super light insane racer as I am ready for the next level. I may just start by replacing the Alien frame with a lighter 5 inch and go from there. I am mid 600 g on mine and that wont compete with 350 - 400 g or less racers. I want to break the 100 mph range.

More then likely that's all pipe dreams and would require a sponsor to move forward. Hard to do when you can't go anywhere or find others to even fly with.

Oh and P.S. The antenna fix held in a bunch of crashes today but the range really suffered. I will dig up that old set up hopefully its a 5 v TX or I am screwed.

 

[PsyBorg]

Got around to swapping out the VTX and Camera. The freebie vtx that came with my original monitor was perfect fit to go inside the frame. I hard wired an old CP antenna to it (I know it won't survive) but I left the shielded wire long intentionally so when it does break I can cut it down and make a dipole out of it without having to remove anything.

The Camera however (the CCD I wanted to use from the Versa) was a 12 v camera so that shot that down right away. That left me with only the eachine CMOS camera (non adjustable) to use. That Camera is not too bad as far as high contrast and slow transitions from light to dark so I think it will be doable. I had to break out the shoe horn to get it all in, soldered and mounted properly but mission accomplished.

For General information.. you CAN use a full size board camera on the Josh B frame but man there is not much room between the props and the pcb edges. I got a few pics to show the changes.







The change over dropped ~5 g from the original set up + the heavy power filter so that's another plus. The batteries I want to get to fly this will also drop another 12 - 15 g so that brings it all back to livable when all is said and done. I did a quick video test with the quad on the table and me walking around with the goggles and I think I may actually be able to fly the play set while sitting at the picnic table now. I will get much more height as well but I STILL am not crossing that field edge into the Alfalfa. I'd never get the quad back if I crashed out there.

Anyway batteries for the day are nearly done charging so time to start packin the gear to head out and fly. Will be back with video to show the changes and how they do.

 

[Airkaos]

You should check the tx03, really good all in one cam, not ccd but pretty good light handling much better than the hyperion, and like $20 bucks, am running 3 of them now.