The best!!

excellent!

Me encanta

excellent

very good

wonderful

Excellent

Its great

Perfect !

Great !

awesome

awesome

Genial

super!

great

GOOD

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This course is a great course for beginners who are stepping into the world of robotics and the perfect course to start a specialization. The course content is exciting and there are a lot of instructional concepts. However, I was not satisfied with the way the content was presented. Being used to the chalk and talk environment, and following online videos where the tutor writes the equations on the screen as they go through them, the " PPT slides and voiceover" method did not attract my attention. But the content of the course kept me going. I found some of the qualitative quiz questions quite difficult as they were not taught in the class explicitly.

Understanding quadrotors, I see that there could not be much done when it comes to programming tasks. Programming tasks Weeks 2 and 3 were extremely easy to code, but tuning the PD gain parameters was the most infuriating task. Even when I got the correct code for Week 3, I was doubting whether I made any mistakes in the code for a long time while the issue was caused by a bad PD gain ratio. The tuning part could be removed by providing a considerable range of possible values of the gains. This would save a lot of wasted time. That being said, I found the final task to be insanely interesting and the satisfaction of solving the final task was extraordinary. I would also appreciate the work done in creating the simulation model and the way the quadcopter was visualized and the trajectory was plotted.

Overall, this course pretty much teaches you all the basic theory you need to know to control a quadrotor. If you dont mind wasting a few hours tuning 6-8 values, you would walk out of this course with great satisfaction.

PS: There are a few videos of quadrotors doing insane stunts both as a swarm and individually inside the course.

I really enjoyed this course and it really hooked me onto this topic, definitely this will not be the last robotics course I am going to follow. That being said there are some points of improvement.

The main parts necessary to program the simulation assignments are covered in the materials, but there are still some of them that need to be pursued independently. Some assumptions have to be made that are not so obvious, I do not know whether it is the intention of this course to do so or not, but since they are minor footnotes that may hinder completely your results, I think they should be made explicit.

The Matlab files available for the course work as intended, what is not so obvious though is how they are intended to work, that is because there is very little documentation about them, it would be great if there was more documentation available, especially for people who have never used such tools before.

Finally, even though I personally enjoyed this course and I think it had an achievable level of challenge for me, I would definitely not recommend this course for total beginners, or people who do not have followed a math, physics or engineering degrees. The way the course is laid out, even if you do not understand the concepts behind each topic you will still manage to answer the quizzes and get the simulations to work eventually, however to truly understand what they mean and be able to replicate them in other environments requires some prior knowledge that cannot be taught in just a few hours.

I really enjoyed this course and felt the material was appropriate in scope and quality for an introduction to Aerial Robotics. I have a few issues with it though.

While this wasn't a problem for me, I feel those who haven't done maths with vectors and matrices before would struggle with the maths presented here.

There was some inconsistency in notation throughout the lectures - though I expect this will be fixed in future runs of this course.

Given how much the programming assignments involved tuning PD controllers, I think there should have been some additional material provided on how to go about doing this.

The difficulty of the last programming assignment came out of nowhere and given that you need to pass all the assignments in order to pass the course, this made it especially stressful. Having gotten almost full marks on the course until that point, the prospect of that all being for naught because I couldn't complete the final assignment in time was incredibly stressful and unfair. The simulation would fail with a Matlab ode45 error - with absolutely no information as to why that should fail. Trying to debug something by guesswork on a time limit is not a valuable educational experience.

I feel all of these issues are fixable though and on balance I think this was a very good course.

I really liked this course, as it presents a researcher's insight into simple, but effective quadcopter motion planning and control strategies. I think this course does require some background engineering knowledge. The last assignment was particularly challenging and really enjoyed. However, I have the following recommendations: 1) the time required for the assignments should be increased to realistic values. Although I found the provided PDFs (in addition to the lectures) useful, it still took time to derive the matrix equation for the snap-trajectory coefficients based on the boundary conditions. Unless the equations are provided in some form, I would suggest a minimum of 9 hours for that assignment. 2) all assignments entail some tuning of coefficients for PD controllers. It can be very confusing to obtain those values, especially if you are not sure what you have done is right and what sort of values to look at. For this reason, I recommend to add an extra step per assignment where the controller is run for a fixed point. That way it is clear from the marker if the equations are correct. Then, a document should be provided on sound strategies for obtaining the coefficients, without a need to look at the blogs all the time.

Overall a good course. But I would suggest the following updates:

-there are many formulas in the course that are not explained, just dropped in the slides

-there are many inconsistencies in notations (for instance the Kv, Kp used sometimes, other times Kd and Kp)

-programming labs should be given in an incremental approach; ex. instead of just requesting a full solution for a given problem, a stepwise approach where the functions are built up to produce intermediate results and slowly add complexity to reach that final goal is much more efficient as a learning tool

-supplementary notes are not available

-slides for the main lectures are available but they are attached to the videos; it would be better if they are added as an item in the course outline. Many other courses on Coursera do the same thing. Also it would spare the presenter to break down the slide pack into parts corresponding to the videos; just place the whole slide pack for a lesson.

This is a more difficult online course that you will come across. I give 4 stars because of the pretty nice content. Learning about writing linear controllers for the desired trajectory in 3D is the best thing we can get out of the course. I don't think this course qualifies as a beginner specialization. Basics (and perhaps little more details) of the topics from Dynamics(Euler equations, differentiation of a vector expressed in one frame wrt to another frame), controls and bit of computation(complexity) is needed. Topics like "Calculus of variation" were simply new to me and you have to work little more harder to understand the different equations which will be presented without any derivation. Biggest downside is TA's or other support staff is not pro-active. Perhaps they will improve in the future runs.

Quite a bit of the assignments was just tuning control parameters. If this is that important a part of designing controllers, you should spend more time on how to tune them. Discuss what physically reasonable or expected gains or damping to see on real world drones in lectures, and physical implications of the control parameters (i.e. is it reasonable to have pitch error gain of 50? 1000? should damping be expected to be 5 or 500? why?). It would also be helpful to discuss more of the dynamics of quad-copters, such as coupling of controls. Are there specific modes of coupled responses analogous to, say Dutch Roll? Are there any controls inputs that can be decoupled form others? Knowing this would make the tuning exercises more educational rather than just guessing.

This course was not so easy( and I mean, that's good ) Some assignments were rather difficult and they forced me to spend several nights for looking the right solution. So, sometimes I felt myself a bit tired) Fortunately I've passed that, before over of session; Good side of this course, it has a lot of material for self-study, i mean, lectures, supplement materials, related some aspects of math and matlab tutorials also good references on advanced level materials ( like Trajectory Generation and Control for Quadrobots ). Although, this stuff requires a thoughtful studying, I have a great interest to get it. I was really impressed by videos of experiments with robots. In other side, some lectures and materials have mistakes.