I am working on manufacturing my quad-copter from scratch. I bought a Raspberry PI 2, Raspberry Camera, MPU9150, system identification set, motors, etc…
I actually succeeded to get data from the MPU and also I finished the Motor identification using Matlab and I got the PID constants.
Now, it is Quad-copter modelling time
To be honest with you, it is complicated for me as I am an electronics and communication engineer. I actually gave up till I saw the PIXHAWK
But, I still have some questions I hope you can answer:
1- I know your system is PID tunable. but there are other aspects that needs to be tuned for precise motion such as “moment of inertial” caused by all the installed gizmos.
Also, what if the installed gizmos on the quad-copter left it asymmetrical. Are these parameters configurable for precise control?
2- There is a point where I want the on-board camera takes control of the quad-copter motion. I mean, by using an image processing software, I want the camera to decide to go left/right, up/down, etc So, can I write this program on your controller and command the quad copter from it or I have to for example use the Raspberry PI then pass the command to your controller. Is it possible and is it easy ?!
1.- you can have different symmetry along pitch and roll axis, but you should avoid asymmetric properties within one axis, (like front=heavy , real=light ) - it will fly, but cannot be tuned to perfection for movement in both directions then. (it’s open source, so given the brain-power, it can still be done if really needed.)
2: yes, you can have an Linux computer process images and control it very simply by using Guided mode, or injecting RC commends , or have the same computer run ArduCopter code as well. how “easy” is , will depend on your programming skills. - but it’s certainly done before, a lot of times, using different methods.
First of all, thank you very much for your answer .
1- Second point is crystal clear now.
2- Regarding the first point:
From my little knowledge regarding “Control Engineering”, I found that if you want an accurate calculations of the PID constants of your, you need to construct a model on Simulink specifying all the parameters you are interested in (high fidelity mode, low, …) then use the Simulink PID tuner to get the best PID constants.
How is that done in the APM software !?
3- You said asymmetric configuration is not preferred, but can be achieved if necessary.
How could I start to learn this stuff ?
4- You said “you can have different symmetry along pitch and roll axis, but you should avoid asymmetric properties within one axis”. If you please, could you elaborate more about this point because symmetry is about planes not axes so I can’t understand what you refer to to be frank with you
Do you mean different symmetry along pitch and roll axis is accepted, but yaw is not? or do u mean asymmetry along ANY two axes is acceptable? and why is that please?
Sorry for the toooo many questions.
I really appreciate your help
