erikspencer's blog View Details
Posted by erikspencer | Jan 20, 2019 @ 01:35 AM | 1,517 Views
Little tool that implements many of the ideas presented in prior blog post here.

Tool link: https://erikspen.github.io/betaflightratestuner

Name: rates_tool.JPG
Views: 1
Size: 179.8 KB
Description:

Over-the-top Highlights:
  • Tired of Max deg/s changing every time you change Super Rate? Set it to a fixed value!
  • Ever explore ways of shaping the curve from mid- to full-stick? A simple "Shape" parameter allows you to quickly cycle through all possibilities!
  • As Bardwell has taught us, setting Expo in Open TX is an evil thing that kills precision. But ever wonder about negative Expo? Easily explore the possibilities this adds in shaping the rate curve! Add center-stick precision! Grow the curve faster! Greater independent control of Pitch and Roll!

Posted by erikspencer | Dec 30, 2018 @ 02:26 AM | 1,375 Views
I thought we'd have a look at some of Velocidrone's top racers who've had quite a bit of success on real tracks as well: SFPV and Holdox.

When looking at their rates, I'd encourage thinking of them in terms of:
  1. What is the slope at mid-stick?
  2. What is the max deg/sec?
  3. How does Yaw compare to Roll or Pitch?
  4. What is the general shape of the curve between mid-stick and max?

SFPV RATES
Name: sfpv.JPG
Views: 28
Size: 154.6 KB
Description:
Observations:
  • SFPV uses fairly low sensitivity at mid-stick. On Roll/Pitch the slope is 0.8. On Yaw, it's 0.6. (Lower sensitivity on Yaw is common)
  • At 239 deg/s, his Yaw is quite low.
  • He uses zero Expo (typical), and uses Super to control curve growth. This means the slope of the curve grows faster than linear, in a consistent manner (we'll explain later).

HOLDOX RATES
Name: holdox_correct.JPG
Views: 16
Size: 151.0 KB
Description:
Observations:
  • Holdox max deg/sec is fairly high at 524 deg/s.
  • Yaw/Pitch/Roll all have the same max deg/s.
  • Like other racers, his Yaw is less sensitive at mid-stick compared to Roll and Pitch.
  • His equivalent slope at mid-stick is 1.45 on Roll/Pitch and 1.03 on Yaw. Substantially higher than SFPV. (a lot of variation between racers)
  • He uses zero Super, and uses Expo to control curve shape. Meaning, the curve grows slightly faster than linear of the first half, and growth is more exponential in the latter half.

The last bullet probably causes the most confusion. Basically, SFPV has used the traditional approach of setting a Super Rate value to control curve growth, whereas, Holdox sets the max deg/sec using RC Rate,...Continue Reading
Posted by erikspencer | Dec 10, 2018 @ 09:11 PM | 1,423 Views
First ever vertical box-frame w/ split-level, I think.

Also, just for looks, first ever slanted roof (using only carbon). Supposed to give a smaller projected footprint when flying at angle, ...but most 3d printed pods already do this.

These frames are becoming popular with some German and Swede pilots for their flight characteristics. ( Carbix frames or Blitzfpv frames ).

Why? I think the gist is low-drag, reduced drift, and perhaps more-directed airflow (?). The box-frame distributes loads well, allows just 2mm arms, so it's not horrible on weight.

I have a 66 gram version (no hardware weight) getting approved on Armattan Productions, mainly just to show this can be done w/o being too heavy or expensive--I expect under $40.