Create and manage motion links

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Create and manage motion links.

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After completing this video, you'll be able to create a motion link

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in fusion.

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We want to begin by opening two sample data sets, the sample engine assembly,

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motion link dot F 3D

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and the steering

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rack dot F 3D.

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We're going to be taking a look at the creation of what's called a motion link.

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We already understand the basics of the application of joints and

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asalt joints in our assemblies.

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We now want to talk a little bit more about motion links.

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Motion links are ways for us to connect

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multiple joints together and link their movement.

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In this case,

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what we're going to be doing is linking the revolute joint for the starter motor

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and the revolute joint for the crank.

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When we select these two joints,

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notice that as the starter motor turns on the left hand side,

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the crank also rotates in the same direction by the same amount,

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we have the option to reverse these.

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Meaning that as the starter motor turns in a clockwise fashion,

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the crank shaft is turning in the counterclockwise fashion,

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we can also dictate the amount that each of these move.

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For example, the first selection, we may want to move 100 and 80 degrees

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while the crank is moving a full 360 degrees

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playing around with these motion links on a simple revolute set of

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joints is a great way to better understand how they work.

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Once we say, OK,

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now as we manually move one of these items, the other one is gonna move as well.

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So now for every full rotation of the starter motor,

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we've got two rotations of the crankshaft based on

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the values we put in our motion link.

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If we take a look at the steering rack,

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the steering rack assembly has a revolute joint for the steering wheel,

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but it has a linear joint for the rail and it has a gear in the center.

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What we need to do is identify all of the different

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motion links that need to happen to make this assembly work.

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First, let's go to motion link.

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We've already looked at using two revolute joints,

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but the motion link can work between different types of joints.

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In

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this case, a revolute joint and a slider joint.

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You'll note that as the revolute joint is moving,

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the preview is showing it's moving just a little bit on the teeth

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and that's because we've got way too big of a ratio.

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Let's go ahead and take this angle down to 10 degrees,

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reverse its direction.

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And we can now see that we're a bit closer to getting the motion correctly.

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In this case, 10 degrees is still a bit much.

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Let's go down to five degrees and see if we can get the ratio right.

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We can see that five degrees is not gonna work in this instance.

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So it needs to be larger.

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When we're designing a gear pair, we know the specific amount of teeth.

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And we also know the distance between those teeth.

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When you're designing a pair of gears.

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In this case, a rack and pinion or any other gear set,

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it's important to know and use the number of teeth that

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you have for the variables inside of our motion link.

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Now, let's go ahead and create one more motion link.

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This time, we want to create a motion link between the steering wheel, revolute

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and the gear.

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We want to make sure they're going the correct direction.

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And

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we'll say, OK,

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so as I turn the steering wheel to the right,

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we can see that the rack is moving to the left.

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As I turn it to the left, the rack is moving to the right.

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This allows us to create complex assemblies of components

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and give some sort of relationship or emotion

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link between multiple joints in our assembly.

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Using this type of motion link allows us to use

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simplified versions of mechanical motion for things like revolute and sliders

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and connect them to other portions of our design.

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Once we're done with this,

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let's go ahead and make saves and then we can move on to the next step.