'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:
- two 0.8mm copper wires (used for welding) cut to 77mm and solder to the end of coax cable. Here I've used RG174
- put that thing into a 3D printed casing
- put antenna tubes around wires. I got mine from here: https://goo.gl/HrWNcY
- glue everything together
- you are done!
Finally, much later than I originally expected, Crossbow LRS, my DIY medium range RC radio link was used to control something that flies. Not much, and not far. It was only my experimental 6" GPS Racer quadcopter. And I reached only 350m. Small steps, I had no intention to beat and records after all.
Just as reminder, by RC link is as follows:
- Based on LoRa32u4 II development boards
- Semtech SX1276 868MHz
- Programmed with Arduino
- Planned range: up to 5km
Next test, this time without twitching, in a few weeks.
Motor winding adventure continues. In this video I show and tell about:
- 12 coils (12N)
- 14 magnets (14P)
- dLRK winding schema
- WYE and Delta termination schemas
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…
I’ve described my Dropship Glider Project here. Previous weekend I finally tested its ability to glide when dropped from a drone 50m above the ground. And well… to be honest, I failed hard this time. Just see this short video from FPV camera:
Dropship survived two drops. After second one, AIO camera/transmitter combo got damaged. Continue reading Project “Dropship glider” – failure #1
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…