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When we are working with evil inertial matrix is very important.

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And you have faced a little bit from the last week.

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Right.

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Now let's dive into the solution for that.

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I am going to open up my lab for this and I am going to press file import mesh to import my mesh.

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I have saved this location of my package so I don't have to navigate into the folders.

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Then Misha's and Basslink.

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This is our mesh mesh level.

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We are going to extract the properties we can.

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We don't need to solve the equations.

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We just need the solution to mesh that is going to help us in that going to filters.

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And I am going to do a normal curvature, quality measures in computations and then computations.

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We are going to perform compute geometric may use this option uses compound compute a set of geometric

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mesh point flow bounding boxes and stuff like that.

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Let's click it.

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And it has calculated already if you see in this small window we can see there are a lot of things.

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What interest we have is the inertia matrix.

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So from this point.

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In this point, I'm going to copy it, which is a small portion, and I'm going to open a new tab and

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paste that here, not saving it.

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So mesh volume is 0.00624 and initiate insert is very, very, very small values.

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Actually, if I implement this equation, they are not going to be solving the problem.

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Why?

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Because from my experience, we need to have some more defined values.

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For that, we need to scale our mesh and again, we compute things for that.

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So what I am going to do is go into filters, normal Richard orientation and I'm going to go into transform

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scale and normalize.

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Here I'm going to say scale my mesh ten times makes each size ten times bigger.

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So ten and in y axis, then in the z x is ten uniform scaling and apply.

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It has made my mesh so big.

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Now if I press filters.

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Computations.

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And compute geometric measures.

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Let's see the inertial metrics.

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Now I'm going to copy it again and bring this thing here.

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So this is show metrics.

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You can see we have now more values, meaning, more explanation.

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So this is one time process, but it is a little bit hard.

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Let's solve it and then we will enjoy our logo.

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So the first step we have to do is to divide our inertia metrics with the volume that has been given.

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Okay.

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So if we start dividing the values, I'm going to just divide the mean values.

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Which are I x, x, I viva.

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And I said, okay, let me bring in the calculator.

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Okay.

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So what we have here.

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2.12790 divided by what is the volume?

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6.241081.

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I'm writing full value.

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I'm going to copy it because we will be needing again and again.

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So 0.340909.

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This is 8xx for a viavi.

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We are going to see it is 7.574817 divided by the volume

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1.21371.2137.

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Again, we are going to do eight for 8.27711 divided by the value.

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1.3261.1.326.

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I know it is a little bit off from robotics, but you need to do this if you want to keep on working.

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That is equal.

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Once for a robot I have written this file as well, which I have documented all of this for example.

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These are the same values we are currently getting.

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We first perform the scaling to x is equal to ten, meaning scaling factor was ten then the division

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of this inner shop in matrix.

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By the value we obtain this values for all of the geometric values divided by the volume.

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Then we need to perform.

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Another division, which is scale value squared.

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So these were the values and they were divided by 100, Y 100 because scaling factor was ten.

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So everything was divided by 110 squared is equal to 200.

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So the inertia matrix became this thing and this is our inertia metric for our robot, but.

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The volume, the mass value is going to be deciding what inertial metrics is going to be.

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Because if we said one kilogram of mass for the beast, this is going to be the inertia metric.

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But if we say to kilograms of mass for the inertia metrics.

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Two.

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Two kg for the base link.

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Then we need to multiply all of these values.

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We do.

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So this is the basic workflow for calculating the inertial metrics.

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I know it is a little bit hard, but we have to do it when we are designing our custom robots for physical

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simulation.

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Now, I have done that for you.

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All of the values of inertial metrics are selected according to the mass value that I have given.

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Everything is selected accordingly, and mass value is specifically taken into consideration after multiplying

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the computed inertial metrics.

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Now I think it's time to run my sport.

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So let's first of all can relate because we have made a lot of changes and run the MI sport.

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Let's see what happens.

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I'm curious, by the way, like not.

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So this time Robert is not flying in the air and it is standing right at the.

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Point of origin.

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If I view the inertia this time, it is only encapsulating the bodies that are.

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Containing that inertial metrics, for example, wheels.

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Inertial metrics is just the small box in which the body of the wheel is encapsulated.

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The box for the base is not that correct, but still it is reasonable and our robot is not excluding.

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Coming to the point of I caster, there is some sort of problem with that, but I think it is working

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fine and it might not cause any problem.

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The point here is a robot is moving and it should not move.

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It is moving for only one reason and that reason is no controllers are currently installed.

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Talking about the controllers in the next video, we are going to install the controllers, take a look

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how they work and how our robot is going to be taking actions in this simulation.