New 250mm Build Project

Frustration with getting the ESCs to work. Built with:

  • 250mm Frame
  • F4 Revo FC
  • Matek PDB
  • Racerstar MS-Series 15A ESCs
  • EMAX XA2212/980KV Motors
  • GemFan 5030 Propellors
  • FrSky XSR+ Receiver

Wired motors with CCW ESCs wires switched; CW were wired straight across.

Fitting the components on this frame was a challenge as well, as the PDB wasn’t designed with the frame cavity in mind. Also, the PDB called for 3-4S, so my 2S batteries were going to sit this out.

Wiring the FC was also troublesome, though all on me. First time installing pins, chose the ESC connections for this method. For ESCs, I only needed Ground and Signal, so I cut up pins for the top and bottom rows of vias. The spacing for the female connectors to the pins was too tight to fit the connectors adequately, so that took some adjusting.

I avoided a potentially huge mistake. I got turned around on the schematics when wiring up power to the FC, and mistakenly wired two positive vias on the FC to the 5V feed from the PDB. ESCs wouldn’t start up properly, USB said the device was drawing too much power, even measuring the PDB feeds to the FC would come up with just millivolts. Finally, I corrected that, and was then able to make headway on my ESCs.

Trouble with the ESCs… random attempts at getting proper protocol selected, finally got it to MULTISHOT, and then calibrated in BetaFlight.

Initially, this FC was flashed with RaceFlight, but with all the trouble I was having, I flashed down to BetaFlight. I think I can still go back to RaceFlight since all the problems were of my own making.

Big lessons on motor mounts needing to match frames, btw. I had ordered some Kensun 1806 2300KV motors, but while the prop shaft was the correct size for my 5″ props, the closer pair of screw holes in the motor were too narrow for my frame; this was after ordering this size motor based on suggested from the frame’s product page.

I’m punting here, using my old EMAXs, my first El Cheapo brushless purchases, along with the ESCs which were Christmas 2016 specials, no longer even listed on Banggood. In order to use the EMAXs, though, I drilled out my 5″ props to fit the larger prop shafts… we’ll see if this was a good idea, I worry about the balancing of the props.

Overall, good practice soldering. I was surprised over and over at how resistant to re-melting my solder joints were. Even with flux, tightening my solder iron… 370° C didn’t seem hot enough. I didn’t change the temp, though, just worked through things slowly, getting more of a feel for working with solder in its various states.

I attached the FrSky XSR+ receiver that was installed on the used Atom V2 that I bought. This will be the first attempt at binding with a Taranis, the first time I’m using a protocol other than DSM2/DSMX. The Rx is wired, and powers up. This is my next step.

Here’s a pic with props dry fit:

Adafruit ftw!

Documentation and Tutorials
——————————————————
1 Watt Cool White LED – Heatsink Mounted
 Tutorials: [[http://www.adafruit.com/products/518#tutorials]]
Adafruit LED Sequins – Royal Blue – Pack of 5
 Tutorials: [[http://www.adafruit.com/products/1757#tutorials]]
Adafruit LED Sequins – Ruby Red – Pack of 5
 Tutorials: [[http://www.adafruit.com/products/1755#tutorials]]
Adafruit LED Sequins – Emerald Green – Pack of 5
 Tutorials: [[http://www.adafruit.com/products/1756#tutorials]]
SMT Cool White 5050 LED – 10 pack
 Tutorials: [[http://www.adafruit.com/products/682#tutorials]]
Adafruit LED Sequins – Warm White – Pack of 5
 Tutorials: [[http://www.adafruit.com/products/1758#tutorials]]

Eachine F4 Brushed FCB

http://us.banggood.com/Wholesale-Warehouse-Eachine-32bits-F4-Brushed-Flight-Control-Board-Based-On-Openpilot-CC3D-Revolutio-For-Micro-FPV-Frame-wp-Usa-1084264.html

Great info here: https://forum.dronin.org/forum/d/200-eachine-f4-brushed-flight-controler/7

dRonin tune: https://dronin-autotown.appspot.com/at/tune/ahFzfmRyb25pbi1hdXRvdG93bnIYCxILVHVuZVJlc3VsdHMYgICA4Ky5hQsM

…and I’m only now understanding that dRonin is another configurator: http://dronin.org/

Decimals in your PIDs, or not?!?

I saw a bunch of screenshots of PIDs with decimal values. Today, in CleanFlight, I can’t enter decimals. I asked about this in a chat room, and learned that…:

the decimals were not really supposed to be there. Use the same numbers with no decimal, it will be fine….It just means they finally fixed the configurator

Supporting educators through Patreon

Joshua Bardwell inspires me simply because of his devotion to educating as fully as he does. I’m amazed at his devotion, and grateful to be able to support him.

https://www.patreon.com/thedroneracingengineer

Bruce Simpson is amazing as well, just watch any of his videos! And this is his full-time gig, so support the man and his family!

https://www.patreon.com/user/posts?u=2951605

Brushless vs Coreless

ref: http://www.rctech.net/forum/89282-post2.html

Coreless motors are similar to what we now use, the difference being that their windings are not wound around an iron core. This makes the armature much lighter, so they spool up a lot quicker. Coreless motors have brushes and commutators, and will work with normal speed controls.

Brushless motors do away with the brushes and commutator, they need special speed controls to handle the switching that is normally performed by the brushes and comm.