I have a project I want to show to a University so if the parts I bought are broken on arival at least the students or prof I showed to will want build & at least I get to see it. I bought many robotic parts and many broke on arrival. Even a store bought one! I don't know if I'm just doing something wrong miscarrying but I'm scared to buy without my backup plan which is to see other students teachers enjoy my concept coming to life and them getting to keep it making me just as happy as I get to see my concept come to life. Sounds outrageous to go to a Uni just to have a decent chance of failing to bring out my concept but it's not for nothing, I get to hang out at the Downtown which has many fun places to go to since it's in the literal center of the town :).
Thank you Pranav for this great video, Actually I am stuck at the last part where if I implement trajectory tracking along X and Y , the quad rotates and crashes as you have shown in the video. Can you provide me some help about this ?? Thanks in advance.
I have not programmed to quadcopter to do trajectory tracking. You would need to linearize the system and then use a linear quadratic regulator to track.
Hello, thank you for your vido! Very good explanation. One think came to my mind. In case of Torque along X and Y Axis (page 1). Why there is not Tx = L/2 * K * (w4^2 - w2^2). I mean why there is "L" not "L/2" as the distance to axis of rotation for both forces is exactly "L/2"?
It seems odd to me that we do not transform the forces (like F_z) from the body-fixed coordinate system into the world coordinate system. Did you neglect this for your calculation? Or am I mistaking? Simple example: If I roll the quadcopter by 90deg, then the rotor force in the vertical direction z will be zero and instead fully act in direction y.
There is R or rotation that multiplies with the thrust force from motors; it is in the notes. Also note that linear equations are in world frame but rotation equations are body frame-- this is standard in rigid body derivations
In my opinion, it is not efficient for beginners to learn from a book. And definitely not if it is a project. If you have a project in mind, I would suggest you search material relevant to the project (e.g., code, videos, presentations) on the web and learn on the go. Also, most textbooks are good with theory, but they don't really show numerical examples, which I think define most robotics projects. This is something I have tried to address in my videos. You can find all material here: tiny.cc/pranavb_robotics
How should I set my initial angular velocities such that I can get straight motion in x direction. coz if I tried to do rotation along y-axis it falls down I can't set the motion such that I get torque along y axis and also at the same time it does not decent along z-axis? Please guide
You need to do that by designing a controller. I have not covered controller design in this video. I recommend using LQR controller. See this: th-cam.com/video/OcJRH6-7zQI/w-d-xo.html
@@sampatil9468 the perpendicular axis theorem is only valid for planar geometries, not for general bodies. In general you can set any values to the three inertias
Can u please help me in calculating power consumption of quad with respect to variation in cruise speed (power bucket graph) and how quad's pitch angle varies with variation in cruise speed
Sir can I've the MATLAB as it is not clearly understandable in the video. And I found this tutorial very informative. So could please help me by sharing the MATLAB code. It would be very helful for me. I'm following your Robotics course.
Hello Thanks so much for the greate content prof , I ask myself why in many literature g is assigned with 9.81 and in some others it is -9.81 ? can you kindly clarify this to me ?
@@pranavab hello Dr thanks, i inspected the axis the z pointing up always and the gravity in the negative of the z axis. see 18:45 the inertial frame points up and g down and you use g with positive value ?
It was from multiple sources, some video online and a research paper. Inspire of being a well researched field, I have not found a single tutorial for beginners. I hope my video meets some of your expectations.
@@pranavab Indeed it is well explained. I need to relate this force derivation to the drone energy consumption would it be possible to share the 3_D dynamics.pdf document you were showing in the video? Many Thanks in advance
@@pranavab Dear Thanks alot for the video , I could not find the 3D_dynamics.pdf file the one you displayed in the video. Can you please share that pdf😊
how can I make this code work for a hexacopter? I made all the necessary changes but i get error on lines like: new_propeller5 = new_axle_x(3,:) + new_propeller; new_propeller6 = new_axle_y(3,:) + new_propeller; patch(new_propeller5(:,1),new_propeller5(:,2),new_propeller5(:,3),'x'); patch(new_propeller6(:,1),new_propeller6(:,2),new_propeller6(:,3),'y');
This video explained it all... I will surely venture into it.
Thanks a lot.
Thank you sir for such an amazing explanation !!!!!
Thank you sir, I learned a lot from your channel. Hope you make more videos.
we are making a hexacopter for my university project and I found this really helpful. thank you
I have a project I want to show to a University so if the parts I bought are broken on arival at least the students or prof I showed to will want build & at least I get to see it. I bought many robotic parts and many broke on arrival. Even a store bought one! I don't know if I'm just doing something wrong miscarrying but I'm scared to buy without my backup plan which is to see other students teachers enjoy my concept coming to life and them getting to keep it making me just as happy as I get to see my concept come to life. Sounds outrageous to go to a Uni just to have a decent chance of failing to bring out my concept but it's not for nothing, I get to hang out at the Downtown which has many fun places to go to since it's in the literal center of the town :).
Sir amazing and understanding video
Thank you Pranav for this great video, Actually I am stuck at the last part where if I implement trajectory tracking along X and Y , the quad rotates and crashes as you have shown in the video. Can you provide me some help about this ?? Thanks in advance.
I have not programmed to quadcopter to do trajectory tracking. You would need to linearize the system and then use a linear quadratic regulator to track.
This is the most USEFUL video about quadrotor. Thank YOU sir.
Awesome explanation.
From where do we get the airframe model? I am working on another configuration Quadcopter.
It’s standard model used in research settings
Pls make a video drone frame and arm length size and thickness according to payload
Thank you sir
Hello, thank you for your vido! Very good explanation.
One think came to my mind. In case of Torque along X and Y Axis (page 1). Why there is not Tx = L/2 * K * (w4^2 - w2^2). I mean why there is "L" not "L/2" as the distance to axis of rotation for both forces is exactly "L/2"?
You are correct. It should be L/2 if "L" is the distance between the 2 diametrically opposite rotors as I have drawn it in the figure.
hi sir
could you tell me how do you find the matrix used in the angular velocity vector
See 22 and 23 on this webpage pab47.github.io/robotics.html
Hi, could you please tell me what are the reference of this pdf called "3D_Dynamics" ?
HOW TO DRAW EULER ANGLES AND UTILIZE EULER PARAMETERS by Schwab and Meijaard (equation 17)
Thank Sir
It seems odd to me that we do not transform the forces (like F_z) from the body-fixed coordinate system into the world coordinate system. Did you neglect this for your calculation? Or am I mistaking?
Simple example: If I roll the quadcopter by 90deg, then the rotor force in the vertical direction z will be zero and instead fully act in direction y.
There is R or rotation that multiplies with the thrust force from motors; it is in the notes.
Also note that linear equations are in world frame but rotation equations are body frame-- this is standard in rigid body derivations
Sir why the force of gravity is not added in the external forces?
Because it is already a part of the potential energy (V) in the lagrangian (L)
sir can u recommend a good book for robotics ? that will be very helpful because my minor project is inclined towards robotics .
In my opinion, it is not efficient for beginners to learn from a book. And definitely not if it is a project.
If you have a project in mind, I would suggest you search material relevant to the project (e.g., code, videos, presentations) on the web and learn on the go.
Also, most textbooks are good with theory, but they don't really show numerical examples, which I think define most robotics projects. This is something I have tried to address in my videos. You can find all material here: tiny.cc/pranavb_robotics
@@pranavab really appreciate...... 🙏🙏
How should I set my initial angular velocities such that I can get straight motion in x direction. coz if I tried to do rotation along y-axis it falls down
I can't set the motion such that I get torque along y axis and also at the same time it does not decent along z-axis?
Please guide
You need to do that by designing a controller. I have not covered controller design in this video. I recommend using LQR controller. See this: th-cam.com/video/OcJRH6-7zQI/w-d-xo.html
@@pranavab How can we set values of Ixx, Iyy and Izz. According to perpendicular axis theorem Izz should be equal to Ixx and Iyy right?
@@sampatil9468 the perpendicular axis theorem is only valid for planar geometries, not for general bodies. In general you can set any values to the three inertias
Do you have PDF or book about this video?
Unfortunately, no. I have not found a book that explains this well.
Can u please help me in calculating power consumption of quad with respect to variation in cruise speed (power bucket graph) and how quad's pitch angle varies with variation in cruise speed
I think that would be simply the motor torque times the angular speed.
@@pranavab I will pls appreciate if you can put something down on Navjit Singh's question for us to benefit from. Thank you
Sir can I've the MATLAB as it is not clearly understandable in the video. And I found this tutorial very informative. So could please help me by sharing the MATLAB code.
It would be very helful for me.
I'm following your Robotics course.
Please download Fall 2020 on this page, tiny.cc/pranavb_robotics
@@pranavab whoa. Just saw your repo. EPIC
Can u give me the photo of your notes for fx and fy
All notes are in the Fall 2020 files here: tiny.cc/pranavb_robotics
Hello Thanks so much for the greate content prof ,
I ask myself why in many literature g is assigned with 9.81 and in some others it is -9.81 ?
can you kindly clarify this to me ?
Depend on the axis. Sometimes positive is down and sometimes it is up
@@pranavab hello Dr thanks, i inspected the axis the z pointing up always and the gravity in the negative of the z axis. see 18:45 the inertial frame points up and g down and you use g with positive value ?
@@Via.Dolorosa whatever convention you use the net effect of g should come out in the downward direction, so -m 9.81 in the coordinate frame shown.
@@pranavab in the matlab script shown, it is used g = 9.81 as a positive value which made me confused ?
@@Via.Dolorosa it’s all correct in the file. The simplest way to check is to keep speed zero and see if the quadcopter falls down.
why are the spinning directions different？
The quadcopter propeller directions are reversed on diagonally opposite motors. Hence opp rotor motion still leads to upward thrust
Oh I see. only in that way can the momont around z be balanced. Interesting design. Thanks!
thang to you can have pdf of the simulation code plc
The MATLAB code is available on this link: tiny.cc/robotics
@@pranavab what's the name of the textbook you based the Lagrangian for the quadcopter?
@@CAGonRiv I did not take this from any textbook. It’s taken from research papers I found on the web.
Could please tell me from which reference this lecture is?
It was from multiple sources, some video online and a research paper. Inspire of being a well researched field, I have not found a single tutorial for beginners. I hope my video meets some of your expectations.
@@pranavab Indeed it is well explained. I need to relate this force derivation to the drone energy consumption would it be possible to share the 3_D dynamics.pdf document you were showing in the video? Many Thanks in advance
@@nithinbabu4962 see Fall 2020 tiny.cc/pranavb_robotics for pdf and matlab files
@@pranavab Dear Thanks alot for the video , I could not find the 3D_dynamics.pdf file the one you displayed in the video. Can you please share that pdf😊
@@muhammadnoumankhan7495 Please see Lec 24, 25, and 26 on this webpage: tiny.cc/robotics
Thank you for the interesting lecture, Can you send me the textbook details..
I did not find any texts that explain quadcopters in fair detail. My notes are from reading research paoers.
how can I make this code work for a hexacopter? I made all the necessary changes but i get error on lines like:
new_propeller5 = new_axle_x(3,:) + new_propeller;
new_propeller6 = new_axle_y(3,:) + new_propeller;
patch(new_propeller5(:,1),new_propeller5(:,2),new_propeller5(:,3),'x');
patch(new_propeller6(:,1),new_propeller6(:,2),new_propeller6(:,3),'y');
You need to make sense of the error message. Usually it is to do with sizes of matrices.
Are you able to resolve this error? I am getting same problem
Impossible to debug without knowing the errors
Hello sir