Explore the process of using joints and as-built joints to assemble a model in the field of engineering design. The article demonstrates the steps for grounding a base component, applying rigid group conditions, setting up as-built joints, and testing the functionality of these joints.
Key Insights
- The article provides a demonstration of using as-built joints, a type of joint that is applied when two geometries are built relative to their placement in the final model. It explains the process of grounding a base component to ensure that it remains immovable whether acted upon by a joint or a click and drag.
- The article highlights the application of a 'rigid group' which defines a relative rigid condition between two or more components. When such a condition is applied, the components maintain their relative position even when moved around.
- The article also showcases how to adjust and test joints for functionality, using the 'revolute' joint type as an example. It explains the procedure for setting up as-built joints, selecting the joint type, and testing the joint functionality by clicking and dragging on components.
In this video, we will apply joints and as-built joints to assemble our model. I will open up Step 04: Joints, and when my file is open, I will close the data panel.
The first joints we will apply to our model are as-built joints. These joints are applied when two geometries are built relative to where they will be placed in our final model. Because my lampshade arm assembly here is already built relative to my base, I can use as-built joints.
You can see as I click and drag on my components, they will move around my model. Notice that when I click and drag on my lampshade arm component or my base component, the bodies will not move independently, but the components will stay stuck together. I will go to the top and hit Revert to move my components back into place.
The first thing I would like to do is to ground my base component. This will make it so that it cannot move, whether it is acted upon by a joint or a click and drag. I will go to Base, right-click > Ground.
You will see a small pin icon appear next to my component, and now as I click and drag, I cannot move my base component. Now we can begin with our joints. If I go up to the Assemble tab, I can see Joint and As-Built Joint, which are J and Shift+J on your keyboard.
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First, let's go to Rigid Group. Rigid Group defines a relative rigid condition between two or more components. If I select these two components and hit OK, now as I move these components around with click and drag, I can see that they will stay stuck together in a relative position.
I will revert that change, and we can continue with our as-built joints. I will go to Assemble > As-Built Joint, and I can see under Type I have many different options. To review all of these options and other information, please watch the Joints video in the Essentials workshop.
I will change my joint type to Revolute and zoom in on this area of my screen. The first component I will choose will be this arm, and second, the base. Now the As-Built Joint command is asking me for a position, or where my joint will revolve about.
I know that it should be the center of this circle, and I can try my best to zoom in and select that point—or, by holding the CTRL key on my keyboard, Fusion will automatically snap to joint locations it thinks are most appropriate. We can see that the flag is on the center of the circle, so I can click while holding the CTRL key. A brief animation displaying my joint will appear.
I can click the Animate button to play my animation indefinitely. I will hit OK, and now I can test my joint by clicking and dragging on my top component. My base is grounded, so it is not moving, and my top components will revolve around that point.
Again, let's revert the position and place an as-built joint between this top arm and this arm here. I will go to Assemble > As-Built Joint, select the top component and then this component. Again, it's asking for position, so I will hold CTRL and select the center of that circle.
My preview animation looks correct, so I will hit OK, and now I can test out my joints with both of my objects selected. Moving these joints may be tricky, and it may take some practice. If we know a specific amount that we want our joints to be set to exactly, we can double-click on our joint and type an exact amount.
I will type 90 and 20 or -20 for this bottom joint. This time, I would like to capture my position, so I will hit Capture Position, and you will see that if I move the object, it will revert to that position. Finally, let's place a joint between this lampshade arm and the upper arm here.
Joints are different from as-built joints in that they will move the first geometry you select to the second geometry. So let's go to Joint in our toolbar and notice that when I move around this component, it is automatically snapping to component and position at the same time. Be very careful when selecting the locations for your joints.
I will zoom in on my model and, again holding CTRL, I will select the center of the circle on this face. Next, I will orbit my model and select the center of the circle on the opposite face here. We will see a preview of our animation, and we can rotate using the rotation slider here.
I can type in an exact amount if I know the amount, or if I don't, I can go to Angle and select Measure. Measure allows me to click on multiple geometries, and it will give me the angle between those two geometries. We can see that the angle between those two lines was 20 degrees, but our lampshade arm is hanging at an odd angle.
I think this may be 90 minus 20 degrees, and it appears as though I’m right. The Measure tool is helpful in finding specific angles, but you may need to do mathematical equations to find exactly the correct result. I will hit OK and zoom out.
Notice capturing position automatically happened when we placed our joints, and that is because joints automatically capture position as one of the default options. Our project is now completely joined, so I can grab this lampshade arm, and you will see complete animation between the arms in my model. I will go ahead and save the file, and in the next video, we will talk about importing geometry and then joining that geometry to our existing model.
I’ll see you in the next video.
