The wet filament is a bad filament. 3D printers hate them since during melting the filament water that it contains turns into steam, expands and creates holes, bulges and other distortions and problems in a print. So filaments are more sensitive to moisture: TPU or Nylon. But even PLA might absorb water if it is kept in a humid environment for a long time. The solution is simple: DIY filament dehumidifier (also knows as filament dryer or dry box) made from the storage box, hygrometer, silica gel as a water absorbent and some window seals. The results are amazing!
‘ve made me an endurance Li-Ion battery pack for my 7 inch endurance quadcopter. With good quality Sony 18650 VTC6 it is possible to get 20A constant current which is enough for an airplane or endurance quadcopter. Works just fine and with reasoable speed of 40-50 km/h I’m getting more than 15 minutes of real flight. Not hover. Flight. And at the end, it still has some juice inside. Not bad, not bad at all.
Details for halfwave dipole for an 868MHz band are quite simple:
More than a year after staring this damn project, I finally decided what goes where. And on top of that, short description how Dualcopters works (or at least should work).
- There are two counter rotating propellers on top. They are responsible for thrust and YAW control
- When both props turns faster, dualcopter gains altitude
- When clockwise propeller turns faster, whole design starts to rotate counter-clockwise. When counter-clockwise propeller turns faster, it rotates clockwise
- Roll and Pitch axis control is archived by two flaps at the bottom of the design moved by two servos
- Since propellers are always rotating, there is almost always enoughair passing through flaps to have enough force for stability control and maneuvers
- To generate enough torque, center of gravity should be far above flaps. This way, even relatively small force on an end of long lever, there is always enough torque for roll and pitch stability
Keeping above in mind, it will look like this:
What is still missing? Place to put battery in and electronics. Next update as soon as I will have any update 😉
Few days ago I mentioned that I'm working on my own DIY long range radio system (LRS) that I named QuadMeUp Crossbow LRS. Today I will share some more details about it.
First of all, I'm not creating anything new or "amazing". There are plenty of "DIY" or OpenSource LRS systems. OpenLRS for example. Or QCZEK LRS that is made from almost nothing at all. And amazing commercial systems like TBS Crossfire.
Is there a place for something else? I think there is. For example, I was so pissed of by complexity of OpenLRS. So many options, so hard to understand. Or do you know how much micro RX for Crossfire costs? And that you do not need 2W of power to fly up to 5km? And most of pilots owning Crossfire never flied > 2km?
This is why, my idea for DIY LRS is:
It's been exactly one year since my last update on Project Dualcopter. On 20th of October 2016 I've posted that there was a progress. Now, 12 months later, I once gain report, that there was a progress…. That was slow….
- I've finally installed control surfaces and servos
- I've finally decided where LiPo will go: to the top of the whole stack. I want CoG as far from control surfaces as possible. They will not generate much force, so I need as much torque as possible. So, long lever FTW
- My daughter called it Flying Bucket. Makes sense, right?
- Plans for next week: battery mount
Half a year after first tries (failed) to wind a DIY motor from Banggood (it’s not in offer any more BTW) I gave it another try. This time, with new tricks in my sleeve and new ESC. It ended up, well, watch the video…
When I saw this video from rctestflight I knew I will build something like that for myself. A voila, few months later it is done. Here is Dropship Glider.
It is 29cm long with 20cm wingspan. Weights 97g AUW and has 21g/dm^2 wing loading. So, in theory, should glide. Somehow… If I got center of gravity right. And did not made ailerons too big. Or…
Delta 6mm Depron “wing” is attached to 6mm carbon fiber rod and has some quite big dihedral: 15 degrees.
The biggest problem was radio link and mixer for ailerons. I could not use my Taranis: I need that for a carrier and only radio control link I had was EM-16 with PPM output only and no way to setup any kind of mixer. The radio just has no “features” like that…
So, took one Arduino Pro Mini and wrote short program that acts as PPM decoder and mixer for ailerons.
- power is supplied by 1S LiPo taken from my Tiny Whoop
- FPV AIO Eachine TX02 also taken from my Tine Whoop
- 5V is supplied from cheap, regulated, step-up converter
- 3rd servo is to release tether
First flight, or rather drop, tomorrow. There will be a video from the event of course…