cnpcshangbo / simscapefopd

Simscape drone altitude control with fractional order proportional derivate controller

simscapeFOPD

Simscape drone altitude control with fractional order proportional derivate controller

Forked from:

https://www.mathworks.com/videos/quadcopter-simulation-and-control-made-easy-93365.html

Cititions:

@inproceedings{shang2018fractional_simscape_gncc,
  title={Fractional Order Flight Control of Quadrotor UAS: A Simscape Benchmark Environment and A Case Study},
  author={Shang, Bo and Wu, Chengdong and Zhang, Yunzhou and Chen, YangQuan},
  booktitle={2018 IEEE Chinese Guidance, Navigation and Control Conference (CGNCC)},
  pages={1-6},
  year={2018},
  organization={IEEE}
}

Publications:

Bo Shang, Chengdong Wu, Yunzhou Zhang, YangQuan Chen. Fractional Order Flight Control of Quadrotor UAS: A Simscape Benchmark Environment and A Case Study. 2018 IEEE Chinese Guidance, Navigation and Control Conference (CGNCC), Xiamen, 2018, pp. 1-6. (accepted)

To request the preprint version:

https://www.researchgate.net/publication/323933166_Fractional_Order_Flight_Control_of_Quadrotor_UAS_A_Simscape_Benchmark_Environment_and_A_Case_Study

Videos:

Movies on how the simulation works can be accessed at: http://list.youku.com/albumlist/show/id_51604678.html

FAQs:

https://github.com/cnpcshangbo/simscapeFOPD/issues

Feel free to ask your own qustions.

Contact us:

[email protected]

simscapefopd's Issues

Tune speed loop from balance point rather than ground

#5 (comment)

How to understand this flight control simulation platform?

How many parts does the flight control simulation platform have? What does each part do?

Lock some dimensions

I plan to do this after my submission on March 18.

How to deal with the saturation?

My FOPD controller is greatly influenced by the controller output saturation.

visual servoing in Simscape?

https://www.mathworks.com/videos/design-a-pick-and-place-robotics-application-with-matlab-and-simulink-122950.html?elqsid=1522132087626&potential_use=Student

How to compare the robustness against loop gain variation?

First, I'll need to try FOPD and then change the speed loop controller gain to 50% and 150%. The get three curves.

Using IRID

https://books.google.ru/books?id=G_T_cZuLA2ICpg=PA119lpg=PA119dq=impulse+response+invariant+discretization+(IRID)source=blots=WRHo-3lL8dsig=txwM9kUN8Q_Z9lwvt_Bwq0sXxwghl=zh-CNsa=Xved=0ahUKEwj2nYv93dTZAhVBDiwKHZrsBUgQ6AEIKDAA#v=onepageq=impulse%20response%20invariant%20discretization%20(IRID)f=false

“IRID” method YangQuan Chen

How to check the pole in discrete domain?

I am still thinking about if it is ringing effect. We need to check the pole in discrete domain.
http://www.diangon.com/zhishi/jsjkz/201504/00022081.html

How to implement anti-windup in discrete transfer function block?

I found that when I use discrete transfer function block to implement IOPID controller, it makes big saturation.

How to tune FOPD controller parameters?

I plan to tune the FOPD controller according to this:
https://github.com/cnpcshangbo/FOPD-tunner

So the cross point is ki0=ki1=0.2238, when lambda = -0.9693
kp=7.9733

How to understand this piece of blocks?

Hi,
I found a piece of Simulink blocks hard to understand.

From the simulation data inspector, I am able to see that the triggered signal and the virtical position is like that. But why the triggered signal is like that?
The enable control is just step function at 5 sec.

Try inserting a zero-phase-holder to simulate communication delay

Should I tune velocity loop or altitude loop to reduce speed oscillation?

I updated those PID parameters in the simulator.
Altitude loop PID continuous Kp = 8.55, Ki = 8.79, Kd = 1.85, Kb=1, ITAE=0.99

However, the velocity loop has the oscillation.

Should I tune velocity loop or altitude loop?

How to change the plant time constant?

Add a gain before the ADC. Try to add a gain there that is 1, 1.5 and 0.5. Then log the data and result for the journal paper.

How to tune speed loop with a step input?

Speed loop needs more integrator

From this issue #14 (comment)
We know that the speed loop needs more integrator.

How to compare performance when plant time constant changes?

Error after changing the sampling period

Simulation 3 Clear
12:57 PM Elapsed: 21 sec
The sample time 0 of 'Quadrotor_Controller/Controller/Tuned IOPID/Derivative' at input port 1 is different from the sample time 0.1 of 'Quadrotor_Controller/Controller/Tuned IOPID/Gain2' at output port 1. Consider inserting a Rate Transition block between the two ports or clearing the 'Configuration Parameters' > 'Solver' > 'Treat each discrete rate as a separate task' option. Alternatively, you can control the diagnostic action for unspecified rate transitions by changing the option "Multitask (or Single task) rate transition" on the Sample Time Diagnostics pane of the Configuration Parameters dialog box.

Tuned FOPD controller can not perform better than the tuned IOPID controller

I've tried to tune all the parameters in Fractional DD but it didn't work.
Then I found that the speed loop is bad.

Therefore, I have two ways to go now.
#1 Try to tune the speed loop to make it better.
#2 Fix pitch and roll, tune.

How to run the Simulation to get a speed loop performance curve?

As title.

Fitting 10~11 sec or fit 10~20? It is a question.

I can skip this question for now and continue my work plan today.

How to identify the altitude plant?

The next step is to re-identify the plant model for ZPos(altitude) control.
I plan to finish that by using the PID tune APP (refer to the webinar from Mathworks).

So the ZPos plant transfer function is: 0.99217/s/(0.2486*s+1).

How to tune speed loop PID parameters?

Hi everyone?
I am having difficulties tuning the speed loop PID parameters. I followed #2 to get a speed curve and then I changed the speed setpoint to step function according to this: #4. After that I was able to get speed loop step response like this:

Speed loop P=2, I=6, D=0.324786114614273, N=19.7366420228035, ITAE=2.35

How to tune the altitude loop?

PID Tuner is not able to tune this plant.

Why FOPD spread at last?

I tried to increase the solver sampling period from 1/100 to 1/1000, but the curve didn't get better.
It is partially because the model was identified for 1/100.
I am not going to continuous this branch now: https://github.com/cnpcshangbo/simscapeFOPD/tree/Testing-solver-1/1000
I am going to use the currently best result to write up my paper.
numerical simulation result 169545d

How to show ITAE of the speed loop?

As title.

How to convert Fractional DD to discrete?

Finally, we found the reason. I used Fractional DD block in the simulator, however, it is a continuous block, I need to change it to discrete block. Here is what we did:


I added a new Edit to enter sampling period(Ts).

Then I added a c2d command to change the transfer function to discrete.

Why ZPos has a bump at 5 sec? Measuring error?

We need to do discrete simulation before using Simscape.

Discrete simulation needs to be done before using Simscape.