Drive Robot Using Inverse Kinematics in Simulink | MATLAB 2021 | Robotic System Toolbox

This video explains the use of Inverse Kinematics to drive a planar robotic manipulator on a simple trajectory. The manipulator was designed in the previous video using SimScape Toolbox and was driven with randomly generated trajectory. However, in this video Inverse Kinematics algorithm from Robotics System Toolbox is used to drive the same manipulator on the designed trajectory.

[@MikeBazrafshan]

Thanks a lot for your easily understandable explanation. You have specified lower and upper limits for the joints (in the previous video) which are violated by the results as q2 goes above 120 degrees while its upper limit is set to 60 degrees.

[@LearningOrbis]

The simulation will violate the set limits, however, it'll show a high rise in torque that will signify that limit has been breached.

[@martinfillola733]

Thank you very much, this series of videos really helped with my uni project

[@LearningOrbis]

Glad it helped!

[@Dvishonthemic]

can you also show how to do it with signal editor as signal builder is no longer available

[@mern_stack_dev]

Please make a video on Signal Editor.

[@cagdastemel3729]

An extremely smooth explanation. I appreciate your effort.

[@LearningOrbis]

Many thanks!

[@xariel99]

Incredibly well explained and detailed, keep it up!

[@LearningOrbis]

Glad you liked it!

[@zainabsalah459]

You determine these points by theoretical solution or from your expectations. You can explain how you know the values ​​of the points.

[@LearningOrbis]

Considering the size of my robot, I wanted my robot to go to these points in workspace. I provided workspace points to the inverse kinematics block and it gives me the joint angles to which each motor should rotate so that the end-effector reaches the point where I wanted it to be.

[@zainabsalah459]

I am in my master's research and my research is related to robotics and python. Can you help me how to link the two programs?

[@-ahmedbnmohamed284]

Signal Builder was Removed ,, What can I Do with Signal editor ,,, may it Alternator ?

[@shubhendukatiyar1683]

Hello sir! As the signal builder block is no more functional, how else can we feed the rectangle coordinates to the manipulator

[@LearningOrbis]

You can use Signal Editor block.

[@Phoenix25585]

Thanks!

[@LearningOrbis]

Welcome!

[@snrzi8796]

Very informative and detailed video

[@LearningOrbis]

Glad you liked it

[@dr.harmeetsingh6736]

Thank you so much for this video...Appreciate your effort....however, I am not able to find the SIGNAL BUILDER in simulink's latest version. I have checked that in online MATLAB too. Can you please provide me the solution for the same? What else can be used in this case if SIGNAL BUILDER is no longer available?

[@LearningOrbis]

They have replaced it with Signal Editor block. You can use that.

[@raphael650]

Great explanation, you're a life saver. Do you know if it's possible to do the same thing but using only matlab scripts and functions? Or if I can keep the simulink model for graphics representation and do all computation with matlab functions bypassing the inverse kinematics block?

[@LearningOrbis]

Yes, it is possible to implement everything in MATLAB M-Files and Function Files. In that case 3D visalization will not be possible, but you can plot trajectories, velocities etc. to check where your robot is going. Check out MATLAB's help on Robotics System Toolbox to get the names of all the functions that are used to implement simulink blocks. You can use those functions directly in M-Files and your Function files to implement the algorithms.

[@raphael650]

@@LearningOrbis Thank you for the reply!

[@ryidgilani8987]

Hi sir, the points that you defined in the way points are not like the actual xyz coordinates of the robot right, the values are only between 0 and 1, where 0 is not extended and 1 is fully extended in that axis right?

[@LearningOrbis]

No, the x,y,z points I defined are coordinates of the locations in the workspace of the robot where I want the end-effector of the robot to go. '0' means zero distance along a particular axis, 0.3 means 0.3 m distance along a particular axis and so on.

[@ryidgilani8987]

@@LearningOrbis I see, for my robot it doesn’t work like that for some reason

[@akmalhariz9372]

Hi Sir! Ive been following your instruction but I did some changes in links length but I think it wont affect anything. My simulation shows the end effector just spawns to desired positions but not move smoothly between four desired positions just like your simulation. Can you help me to find the solution?

[@LearningOrbis]

Contact me through email and share some screenshot or perhaps your simulink file, then I can look into it.

[@ignatiusjacquesreilly70]

Can you please explain what file you are using as the argument to importrobot() in your m-file? Your workspace says 'DOF2_Arm_A' but it is not clear what this model is, since it was not created in the previous video. In the previous video, you saved a Simulink model called 'DOF_Test1' which was not driven, and you had an unsaved model which was driven by sine waves. Was this second model the same one that you are now calling 'DOF2_Arm_A'?

[@LearningOrbis]

It is the same model only the file name is different nothing else.

[@shaiisrael9038]

Hi, i'm currently trying to implement your solution from the video. However, the arm moves to (0.15, 0.01), (0.15, 0.11), (0.15, 0.01), and then back to starting position. Signal builder is no longer available, and matlab recommends using signal editor. Do you have a solution for implementing editor. Thanks

[@LearningOrbis]

Signal editor bock is similar to signal builder, you can use it. Your first and last (third) way points are same that is why it is moving back to the starting point.

[@wyattsmith5355]

Thanks Bro!

[@LearningOrbis]

Welcome!

[@varun3425]

Hey idk why but my robot seems to move pretty fast can anyone tell me how to slow it down like shown in video also it complied pretty fast is there an error

[@LearningOrbis]

Send me your simulink file snapshot on email.

[@ramihjeij-rr1dh]

Hello, is there a way to insert the x,y and coordinates of the end and output the orientation of the joints?

[@LearningOrbis]

Yes, the Get Transform block gives the complete Homogeneous Transformation Matrix as output. Using Coordinate Transformation Block I am extracting only the position vector, you can use it to extract the orientation matrix as well.

[@JOSEPHBRYANENERIO]

Good day sir, i just want to ask can I integrate this in arduino?

[@LearningOrbis]

Yes, but this analytical approach of Inverse Kinematics cannot be run in real-time. Either you can allow the inverse kinematics to run in simulation and then relay the calculated trajectory to arduino or you have to implement geometrical inverse kinematics in simulink and interface it with arduino.

[@alokvijaybhatnagar1552]

It is an excellent video. My concept has no angular position feedback, ( the motors are stepper motors without encoders) , can I still get the inverse kinematics solved, derive the two linkages' angular position, and get a suitable G code from the exercise. Please explain. Regards,

[@LearningOrbis]

Yes you can do it but MATLAB won't generate G-Code. You can implement inverse kinematics through analytical method or through the method explained in the video.

[@fffrah3074]

Dear sir, my robot reaches every corner of the square but moves in a weird glitvhy way sometimes. Do you happen to know why? Great video by the way.

[@LearningOrbis]

Try decreasing the tolerance in inverse kinematics. May be the inverse kinematics is not producing consistent output because of the tolerance.

[@fffrah3074]

@@LearningOrbis Yeah I solved it, thank you so much

[@gandhigodofwar5872]

Can you share your values​@@fffrah3074

[@MARCOANTONIOMACHADOGONCALVES]

Hello sir, my mathlab doesn't have the Signal builder, is there any other way to simulate the trajetory?

[@LearningOrbis]

You may use Trajectory Generation Block or simple signal generator. Watch my other video on Trajectory Generation to learn how to generate trajectory from Trajectory Generator Block.

[@LearningOrbis]

You may use Trajectory Generation Block or simple signal generator. Watch my other video on Trajectory Generation to learn how to generate trajectory from Trajectory Generator Block.

[@LearningOrbis]

You may use Trajectory Generation Block or simple signal generator. Watch my other video on Trajectory Generation to learn how to generate trajectory from Trajectory Generator Block.

[@huzefaturab9478]

hi sir , well explained, yet i am facing a problem. First, i cannot find limits in my dropdown of revolute joint. Second, how can i change the axis of revolute joint as i want my robot to move along x axis. third while using signal builder constant signal , you changed the values on left point and right point, i am not able to do that

[@LearningOrbis]

Joint limits are there in Joint Block, your MATLAB version might be different and the option might be somewhere else, but it should be there. For movement in x-axis, the z-axis of the joint should be aligned with the x-axis, and now your robot will move relative to x-axis. Keep in mind that a revolute joint will always rotate about its own z-axis. You can use rigid transform block to aling the z-axis with other axes. Kindly view my first video in the series to know how to assemble the robot and change axes. As for the signal builder you can edit any signal, all you have to do is click at the appropriate place to select it. If you still got any unresolved issues, you may contact me at [e-mail] with screenshots of the problems and I'll try to reply there.

[@AWAISTEACHING]

plz tell me it's not working the arm did not move towards the Base(MeanS the End factor). Why? Watched video step by step.

[@LearningOrbis]

Kindly reach me through [e-mail] and share the screenshot of the issue you are getting. I cannot understand where you are stuck. I'll try to help you out via email.

[@ryoka_vlog3519]

hello sir, i want to ask how i can get the DOF data? i saw your videos but i cannot find how to get that. pls teach me. ty

[@LearningOrbis]

What do you mean by DOF data? Kindly explain a bit.

[@mostafamahmoudabdelaziz9470]

which solver you used?

[@LearningOrbis]

It's in the video at around 12:00, I have used Levenberg-Marquardt solver and adjusted it's parameters to speed up the simulation.

[@mostafamahmoudabdelaziz9470]

@@LearningOrbis i do all what you do in the videos but the robot dont track the square correctly can you help me i can send the file to you

[@hosseinsadathosseini6376]

@@LearningOrbis Hello. I have the same problem. My robot does not follow the path. I did just you did. I also watched all the previous videos. Can you please help

[@fffrah3074]

@@mostafamahmoudabdelaziz9470 Try putting 1e-5 in the error tolerances box inside the settings of the solver, it worked for me.

[@santoshkumar-yh2bc]

Dear Sir, Thank you for the informative video. I'm currently working on a Quadruped robot and your videos have really helped me a lot understanding the Simulink and simscape development environment. I have already developed the quadruped robot in Simulink and each legs are being controlled using Inverse kinematics block. Now i plan to autogenerate code from Simulink (Using Embedded Coder) and plan to run it on actual real robot. But the problem i face is that the inverse kinematics model generate huge code (around 10 thousand line of code for a simple 3 dof leg) making it hard to run on Microcontroller. I assume the problem here is that the Simulink uses an iterative Method to find solution, I would like to know if you are aware of any analytical Method of finding solution of Inverse kinematics using Simulink or Matlab ? Kindly provide me any relevant link to generate inverse kinematics solution using analytical method. Also i have tried using both solver (BFGS and Levenberg-Marquardt) for generating code, But i get the same results. Hoping for your reply and guidance on this issue.

[@LearningOrbis]

Analytical method of Inverse Kinematics has to be found by hand for your robot. There is no universal method for automatically finding analytical Inverse Kinematics.

[@mariamnail4830]

what i do ,if i have 4dof ? what i will change in inverse block ? and block made by you or its find in simulink ?

[@LearningOrbis]

Use the rigidbodytree of your robot in the inverse kinematics block and select the last body as end effector. Nothing else should be changed.

[@DEBARPANMAJUMDAR]

11:31 what I would do. if I have 4 joints

[@LearningOrbis]

Use [0 0 0 0] for 4 joints.

[@DEBARPANMAJUMDAR]

@@LearningOrbis thank you for support, although I have already used it.

[@adhraahussam2335]

Hello sir , thank you for your. please help me ,how can I get mathematical model for this robot?

[@jainchaitanya1511]

sir signal builder remove ker Diya hai so Abhi Tessa kerna hai ?

[@LearningOrbis]

Use signal editor instead

[@jainchaitanya1511]

@@LearningOrbis same hai kya sir yo?

[@muhammadbilalali9412]

❤❤

[@zanelangley2324]

Hey do you know if this would work the same with 3 joints? so you could move in the z-axis aswell

[@LearningOrbis]

You can try and make a 3D robot and check for yourself. I'll try to make a video on 3DOF 3D robot in the coming weeks.

[@wyattsmith5355]

did this work for a three dimensional robot?

[@AWAISTEACHING]

hy, kindly tell which file is this Defo_arm_A

[@LearningOrbis]

Kindly watch previous videos where I have explained how to create robot in SimScape. You'll know what this file is and how to generate it.

[@memoreap7410]

Design of a Sliding Mode Controller with Fuzzy Rules for a 4-DoF Service Robot . Sir can you help us in this project please

[@mechatechnology8613]

can be application this program at robot 4DOF and why please...?

[@LearningOrbis]

Yes it can be implemented on 4 DOF or any other number of DOFs. You have to adjust other blocks as well.

[@mechatechnology8613]

@@LearningOrbis ok thank you very much if you have vidio about 4dof send me and very thank

[@dennymenace7952]

already press like and subscribed,.. but please speak more slowly

[@LearningOrbis]

You can watch video in slow motion by using playback speed option of youtube, or you can turn on the captions.