kinematics | JavaScript 6DOF robot kinematics | Robotics library

this is my website that I am developing, and I trying to develop a calculator which depending on the subject and equation your are trying to use, the calculator will give you an answer.

I made two dropdown menus, however, when I hover over the "Physics" menu, for some reason the "Maths" menu is covered. Also, the list for "Physics" is a bit too long and I wanted to make a scroll bar, but I don't know how to.

I tried to look on w3schools and other resources, but I couldn't find a solutions which solved my problem.

I'm trying to make to make my first website with html and css (and js later). I want to make a calculator with a dropdown menu, but I'm struggling to make the dropdown menu as when it is hovered over, the dropdown list covers the menu.

I'm using Overleaf to write a report. I can't seem to get the format just right for the top right corner cell. I would also like to center "Correlation coefficient"

I wrote a C++ module to compute the forward and inverse kinematics for my SCARA robot arm, and I want to wrap this module into Python so that I can use it in another application. For the conversion, I chose SWIG, but it is pretty hard to write the interface file correctly.

In my header of C++ module, I have

I have object 1 with rigid body and box collider, I want it to hit object 2 (also has collider and rigid body) so I can use the collision to stop object 1 for 5 seconds then have it move through object 2 whish has kinematics on

EDIT I just solved the problem with numpy's einsum function. Instead of doing T[:,:,:,0]@... I just Matmul'ed the first two with einsum, then the resulting with the next index, and so on.

I am currently trying to solve the Denavit Hartenberg Equation for a 5 DOF robotic arm forward kinematics. Since i need so solve this for a genetic algorithm, i need to do it simultaniously for n robotic arms.

My current approach is that I define a 4x4xnx5 matrice with all the needed transformation matrices for n robotic arms. I then itarate all n arms over a for-loop, solving each DH-Equation with matrixmultiplikation (See code sample 1 down below). This works but is obviously time consuming. A much smarter way would be to do something like code sample 2, but I then get the following error message (n=500):

"matmul: Input operand 1 has a mismatch in its core dimension 0, with gufunc signature (n?,k),(k,m?)->(n?,m?) (size 4 is different from 500)"

is there a way to do such matrixmultiplikation with numpy like demonstrated in code sample 2?

I am using PyDrake do build a simple model of a Franka Emika Panda robot arm which picks up and places a brick.

I would like to observe how a change in the initial chosen starting position of my brick affects a custom target loss function. Therefore, I would like to use the AutoDiffXd functionality built into Drake to automatically extract the derivative of my loss function at the end of simulation with respect to my initial inputs.

I build my system with as normal, then run ToAutoDiffXd() to convert the respective systems to an autodiff version. However, I get the following error:

I'm trying to make some simple pool game in java script. I have made it but I do not love way of checking if two balls will collide in next frame. I would like to have more easier way to calculate coordinates of balls when collision occurs. I found lot of answers base on collision kinematics, how to handle velocities and directions after collision, but no calculating a position when collision occurs.

As you can see in sample diagram, gold ball is moving slower than a blue ball, and with distance that each ball will have to move on next frame will not be considered as collision. But, as you can see, they should collide (dashed lines).

In that cause I have divided each movement into sectors and calculating if distance between the points is equal or smaller than ball diameter, which is slowing down process when many balls (like in snooker) have to be calculated in each frame, plus that way is not always 100% accurate and balls can go in inaccurate angles after hit (not a big difference, but important in snooker).

Is there any easier way to calculate those (XAC,YAC) and (XBC,YBC) values with knowing start positions and velocities of each ball without dividing ball paths into sectors and calculating many times to find a proper distance?

I have created a Moodle Formulas questions in the field of kinematics with two boards. While I managed to get simpler questions with only one board to work flawlessly, the problem with this question is that the bound values are not inserted into formula's input entry fields. Consequently, the student cannot submit an answer because, effectively, nothing has been filled out. The rest of the question works though, as can be seen when the correct answers are filled in the question's preview.

I provide a Moodle XML file to make it easier to reproduce the problem: questions_formulas_JSXGraph_2boards.xml
You need a current version of Moodle with JSXGraph filter and question type Formulas installed.

The main JSXGraph code is this: