Does open the door pretty well let's see if it can clean as good as a human

Which one should I download in etcher? Nothing is working 😢

in my laptop i have windows, ubuntu 20 and ubuntu 22 server after installing the software it showing only windows and ubuntu 20. it not showing U22

Thank you so much! I just needed this, I may need more tho. If you could do more in depth and more specific examples for Robotic Applications, like the entire projects from zero to hero type of structure would be perfect!

视屏盗用的是西班牙塞维利亚大学GRVC机器人实验室2023年9月的影像资料，和中国的西北工业大学无关。西北工业大学的确在2022年11月15号创下了Longest flight duration of an unmanned ornithopter (single charge)的世界纪录，但是至于这个纪录具体有什么实际意义，可能需要业界人士来分析了。值得一提的是这个纪录在2023 年9月22日就被同一团队破了，可见这个视频做的多差。

This on on the top after the other befroe it the somatice custodians robot's coming soon near you

It's not clear to me why q has 3 DOFs even though it has 4 parameters. Can you please elaborate on this?

Very helpful! Thanks!

I am a complete beginner in ROS and this is an amazing content. Thanks a lot for your effort.

I have developed or directed the development of several large-scale multibody dynamics programs and have never used the Denavit and Hartenberg method, which forces kinematicians to use unconventional methods to fit their models to DH limitations. It is much simpler to split shape matrices into sequences of primitive translations, tx, ty, tz, and rotations rx, ry, rz, in any order. And it is much simpler to represent joints as sequences of primitive translations, tx, ty, tz, and rotations rx, ry, rz, in any order. Just string their spatial displacement transformation matrices together in any desired order, and extract constraints, velocities, and accelerations as desired.

Are robots left-handed? Why are we using left-handed coordinate systems?

The degrees of freedom (DOF) of any articulated mechanism is its mobility number, such as 0 or 1 or 2 or, etc. DOF is also the sum of all constrained joint mobility numbers. A kinematically locked joint has zero mobility or zero equivalent mechanical advantage, and a dextrous joint has nearly unity mobility and high equivalent mechanical advantage. The ith joint's mobility number may be obtained from the square of the norm of the ith row of the constraint Jacobian matrix's orthonormal null-space matrix. The number of columns in this matrix is DOF, as is its norm. The sum of squares of all row norms of this matrix is also DOF, which is why the sum of all joint mobility numbers is DOF. Technically a joint's mobility number is the square of the direction cosine between it and the mechanism's differential constraint manifold. Maximum motion and mobility is obtained when the joint is closely aligned with the manifold's surface, and minimum mobility when it is orthogonal to or nearly orthogonal to the surface. The most reliable way to get the correct DOF, which can also fail, is to apply Gaussian Elimination with Complete Pivoting (GECP) to a very accurate Jacobian matrix associated with the articulated mechanism's kinematic constraint equations. If the model has n variables and the Jacobian matrix has rank r, then DOF=n-r of the variables are independent. The wrong rank r and thus the wrong DOF may happen when mechanisms are over-constrained and some or all of the joints must be perfectly aligned to get any motion at all. At each stage of matrix factorization there is a remaining residual Schur complement matrix. When the norm of this matrix is zero or falls below some predetermined constant, the Schur complement matrix is considered to be zero and factorization stops. Matrix rank r is then the dimension of the resulting invertible factor matrices, not the number of rows or columns of the Jacobian matrix. Problems occur when the Jacobian matrix is noisy or in error for whatever reasons, and the noise or errors contaminate the remaining Schur complement matrix, causing the algorithm to incorrectly increase rank r and decrease DOF. Get the wrong DOF and the mechanism model will not perform as expected. A good example is a 6R Bricard mechanism with a 6 by 6 Jacobian matrix. When the six joints are laid out correctly and precisely the mechanism will have one DOF and articulate. Thus the matrix rank r must be 5, so DOF=6-5=1. But even tiny amounts of constraint error will lead to tiny amounts of error in the Jacobian matrix, and GECP will return a rank r=6 and DOF=0. Before factoring the Jacobian matrix to determine matrix rank and model DOF, the constraint violations must be minimized to the extent of available precision, and hopefully that will be enough for GECP to get the correct matrix rank and DOF. Incidentally, see what the Chebychev-Grübler-Kutzbach criterion is for this mechanism and ask yourself which method is more likely to be more accurate most of the time. See "Chebychev-Grübler-Kutzbach's criterion for mobility calculation of multi-loop mechanisms revisited via theory of linear transformations" by Grigore Gogu

What if a robot had learned what a toddler learned in her mother's kitchen pulling and pushing on the knobs and handles of doors and drawers? We sense where and how to push and pull and twist on objects to make them do what we expect. Imagine a robot with template kinematic and dynamic models of objects surrounding it embedded in its brain with the ability to probe mechanism mobility anywhere and in any direction and pick what works best instead of always by trial and error. A mobility number is like a perceived mechanical advantage. If the mobility number, which is the square of a direction cosine relative to the differential constraint manifold surface, is close to unity, the door will open easily, but if it is zero or close to zero, the door will not budge.

It's all in how one interprets it. Forty years ago I developed my own matrix-based spatial algebra notational convention, similar to Featherstone's, and used it to develop a general purpose, 3D rigid multibody dynamics modeling and simulation program for a fortune 500 company. Let there be one inertial frame 0, and believe me, the numerical processing is much simpler and more efficient when all vector coordinates are expressed in the same frame 0 and all bound vectors are moved to the same frame 0 origin. Imagine a spiky ball of hundreds of bound vectors all intersecting at a common point with all those free vectors floating around that you can't seem to lay a finger on. It's sort of like protons and neutrons sitting in the middle of an atom with a cloud of evasive electrons that don't seem to be anywhere at the same time.

But can it unstop a toilet?

Can i get the code??

thanks for this tutorial

amazing coding skills

thanks for this wonderful tutorial

Amazing video, thanks

does this work if there is only ubunto on my laptop

imagine if you are sitting in the office next door, this robot comes to you say hello and then start spraying all over your face😂

Great video, Great explanation esepecially on Grubler's formula ps. I love it when Salma Hayek explains Mechanisms :D

I didn't understand how a rotation and a translation in the same time compose one degree of freedom?

This is fukcing linux

This series has been fantastic - I tried working through the Modern Robotics textbook on my own but it has been difficult for it to really click. Your videos have been amazing, thank you. Will you continue this series?

I am just installing the program and everything with your videos, I have done every step but I dont have the catkin_tools_prebuild document is that would be a problem?

Hello Doctor, why did you not post a series on a mechatronics course or film lectures on the mechatronics curriculum during an explanation at the college?

What about the code brown protocol? 💩

now add SLAM

49:45 can use print(str(time.to_sec()) + " seconds"). The .to_sec() method converts the Time object to a float of seconds then str() casts the float to a string for concatenation.

For getting the Time variable into a float At 49:45 we can use the Time method .to_sec(), then cast the float to a string so we can concatenate with " seconds. e.g. print(str(time.to_sec()) + " seconds")

the one robot tricking the other one to return to the start was absolutely diabolical

21st century and they are still dumbass as fuck

Dr I want to join your lab. Any open position for master degree

Amazing work Dr

Amazin course!

LoL.... That's what they believe a bathroom looks like when someone cleans it. I saw a lot of mistakes.

The norm of the linear velocity component of the Twist vector is 4, not 1.4142 at 19:57. Could you please guide?

catkin init and catkin build commands are not working. it says 'command not found'. Pls help

can you make the same tutorial in ROS2 plz

Dude thank you so much, I was thinking I had to buy another ssd.

Unable to locate package os-uninstaller

Thanks for your high quality tutorials It was pretty perfect 🥂👌🏻

Astounding

This is kind of old isn't it? We had a toy like this in the early 90s from the Air and Space Museum 🤷🏾‍♂️

To the guys who have built it, you are destroying people's jobs for your only benefit !

Wow

Wow

Wow