I will be honest with you. I'm disappointed with the flight performance of 7-inch quadcopters. It feels like there is something missing in there. Everything shakes, jello is all around the HD footage. It's not even close to the smooth flight I was hoping for. One thing is sure, just horizontally scaling up 5-inch frame to accept 7-inch propellers is not a way to do it.
In this series of videos, I will show you every major step I took to improve the flight performance of my 7-inch iFlight XL7 v2 frame. What is important, when I write those words, I do not yet know if I will succeed or not... Let's begin our journey into the world of 7-inch frames and propellers...
The one with the description of the problem
In the first video of the series let's concentrate on what I think is wrong with 7-inch drones:
- bigger props = lower noise frequency and higher amplitudes
- longer arms = lower resonance frequency
- if the vibration amplitude is high enough, arms enter a low-frequency resonance
- this is visible on HD footage as a jello
The one with the soft mounted motors
The first of the ideas on how to make smooth flight: soft mounted motors. After all, soft mounted flight controller and gyro are THE THING, right? It's been already tried on smaller, 5-inch FPV racers. Will it work on bigger drones are well? Let's find out!
The one with a better motor soft mount
The second try to soft mount motors. This time with TPU/rubber on both sides of the arm. And no glue on bolts heads. Will it work better? Let's try it out!
The one with soft mounted arms
OK, not everything I do works like expected. For example, soft mounted arms... Why could have known it will be such a failure. Looks like it's either not working, I did something wrong or my frame really sucks... oh well...
The one with hard mounted GoPro
If soft mounting the motors works but soft mounting the arms do not, maybe something similar is happening with a GoPro. After all, who said that GoPro installed on an elastic mount is a good idea? With that in mind, let's try to attach GoPro Session 4 firmly to the frame and see what's going to happen with HD footage!
The one with stiffened arms
If too much flex in the arms is part of the problem, why not to fix it by removing some of that flex and making arms stiffer. How to make something stiffer? Pretty simple. Just make it thicker by gluing something to it. In the case of carbon fixer drone arms, this something can be carbon fiber square profile. Will it work? That is the question I will try to answer in this video!
Parts that work great on 7-inch FPV drones
Video are great, but sometimes there is nothing better that a written worlds. In this entry I list the most important parts: frames, motors and propellers.
If you want to know more about elements of your first 7-inch drone, you really might want to read it.