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# New helper tool for setting Betaflight rates

Posted by erikspencer | Jan 20, 2019 @ 01:35 AM | 1,795 Views
Little tool that implements many of the ideas presented in prior blog post here.

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!

# Racing rates, A tutorial

Posted by erikspencer | Dec 30, 2018 @ 02:26 AM | 1,674 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

Observations:
• SFPV uses fairly low sensitivity at mid-stick. On Roll/Pitch the slope is 0.8. On Yaw, it's 0.6.
• 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

Observations:
• Holdox max deg/sec is fairly high at 524 deg/s.
• Yaw/Pitch/Roll all have the same max deg/s.
• Yaw is less sensitive at mid-stick compared to Roll and Pitch.
• His equivalent slope at mid-stick is 1.44 on Roll/Pitch and 1.03 on Yaw, substantially higher than SFPV's 0.8 and 0.6.
• 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, and then applies Expo to flatten out the middle portion. In terms of the basic shape of the...Continue Reading

# Box-frame vertical arm concept frame

Posted by erikspencer | Dec 10, 2018 @ 09:11 PM | 1,724 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.