• Fusion

Assembly modeling using Ground, Group, and Joint

Apply several techniques for assembly modeling to the Saw model, including how to ground components, create a Rigid Group, and create an As-built Joint.


00:03

We can create joints and assembly model at any time in fusion.

00:06

But we only need to create joints if we require movement or if

00:11

we need to use the joint in the simulation environment in fusion,

00:14

if we don't require movement for our 3D models,

00:17

and we don't need to simulate working joints,

00:20

we can very quickly lock down our entire 3D model by creating a rigid group

00:25

to do this drag a selection window around the entire

00:28

model from right to left to select all the components

00:32

and from the tool bar. If we click assemble and then choose rigid group, then click.

00:37

OK. In the dialogue,

00:39

rigid group locks, the relative position of the selected components

00:43

and the components are treated as one single object when moved,

00:46

a rigid group is similar to a rigid joint.

00:49

But the main difference being with a rigid group,

00:51

you lock the origins of the components together with a regular rigid joint.

00:56

You have to reference features such as a face or an edge.

00:59

And this requires many more processes than simply creating a rigid group on its own.

01:03

However, in this tutorial,

01:05

we want to create some movement between some of the internal mechanisms of the saw.

01:09

So I'll click to undo the rigid group in the file menu

01:12

to begin the assembly modeling.

01:14

I'm going to convert the right side casing from a body to a component

01:19

in the browser. Right? Click on body 19,

01:21

then select create components from bodies.

01:25

Here's our new component, double click on the name and name it to right casing,

01:29

then press return on the keyboard.

01:32

So here's my new casing component on the model

01:34

and I can click and move it around.

01:37

I want to ground the casing.

01:39

So let's right. Click on right casing in the browser.

01:42

Then choose ground

01:44

the right casing is now grounded and fixed in position.

01:48

So I can now zoom into the mechanics

01:50

and begin to create some movement.

01:53

The reciprocating saw has been designed with a top down approach

01:56

and all the components and parts have been designed in

01:59

context with each other placed in the correct positions.

02:02

This makes assembly modeling the saw mechanics

02:05

much easier because we can use something in fusion

02:08

called as built joints to model all the mechanics,

02:12

abut

02:12

joints are similar to regular joints.

02:15

With the main difference being that as built

02:16

joints maintain the current position of the components.

02:20

So we can only use as built joints if

02:23

our components are already positioned in the correct locations

02:27

to create an as built joint from the toolbar, click assemble,

02:31

then choose as built joint.

02:33

I want to model the movement for this large spur gear

02:36

to rotate around the gear shaft in the center.

02:39

So in the dialogue,

02:41

I choose revolute for joint type,

02:43

I then select the spur gear

02:45

and the gear shaft. Now I need to choose the position for the revolute.

02:49

I'll click to choose this edge here on the gear shaft.

02:53

And fusion provides me with an animation preview of the movement

02:56

and I click OK to confirm the as built joint.

02:60

If I double click on the blue joint symbol,

03:03

I can use my mouse to drive the joint and we can see

03:06

the movement of the spur gear around the shaft is as we want it

03:09

as the spur gear rotates, it turns the crank arm

03:13

with a small rod connected to the spur gear.

03:16

Since the crank arm and the rod are in the correct positions,

03:20

we can use another as built joint to continue the assembly.

03:24

So let's do that and select as built joint from the assembly menu in the toolbar.

03:29

After driving my first joint, I've changed the position of the two components.

03:33

And fusion's asking me whether I want to keep the position that I've

03:36

changed or revert back to the original position of the two components.

03:40

In order to use the as built joint,

03:42

I need to ensure that the components are in the correct position.

03:45

So I won't capture the position of the components and

03:48

I'll click continue to revert back to the original position

03:51

to create the joint. I'll select the crank arm first, then the spur gear.

03:56

Again, our motion is revolute.

03:58

But this time we want the position of the movement here.

04:01

The preview confirms the movement so we can click. OK. In the dialogue

04:06

again, I can use my mouse to drive this joint.

04:08

But this time driving this joint drives both the abut joints in the assembly.

04:13

However, the crank arm isn't moving off the small rod

04:16

and nor is the small rod fixed to the spur wheel.

04:19

So we need to join these parts together

04:22

and we can create a rigid group to do this

04:24

because there's more than one component,

04:26

creating a rigid group is much quicker than creating individual rigid joints.

04:31

For each component

04:32

from the assemble menu.

04:34

Select rigid group, then select the components that you want to group.

04:38

Click the spur gear, join to the small rod,

04:42

the rod clip,

04:43

the small rod bushing

04:45

and then click OK to confirm the rigid group.

04:49

And now when we click to drive the joint,

04:52

all the components move with it

04:57

and we can continue moving our way up through the assembly,

04:60

applying joints and motion to the component parts where necessary.

05:04

And because fusion keeps everything in one single design,

05:07

we can move in and out of workspaces and environments whenever we like

05:11

making modifications to sketches, free form modeling,

05:14

parametric modeling,

05:16

direct modeling

05:17

and of course assembly modeling

05:19

and everything we do is recorded in the timeline.

05:22

So we can go back at any point in our design history

05:25

and make any edits that we need.

Video transcript

00:03

We can create joints and assembly model at any time in fusion.

00:06

But we only need to create joints if we require movement or if

00:11

we need to use the joint in the simulation environment in fusion,

00:14

if we don't require movement for our 3D models,

00:17

and we don't need to simulate working joints,

00:20

we can very quickly lock down our entire 3D model by creating a rigid group

00:25

to do this drag a selection window around the entire

00:28

model from right to left to select all the components

00:32

and from the tool bar. If we click assemble and then choose rigid group, then click.

00:37

OK. In the dialogue,

00:39

rigid group locks, the relative position of the selected components

00:43

and the components are treated as one single object when moved,

00:46

a rigid group is similar to a rigid joint.

00:49

But the main difference being with a rigid group,

00:51

you lock the origins of the components together with a regular rigid joint.

00:56

You have to reference features such as a face or an edge.

00:59

And this requires many more processes than simply creating a rigid group on its own.

01:03

However, in this tutorial,

01:05

we want to create some movement between some of the internal mechanisms of the saw.

01:09

So I'll click to undo the rigid group in the file menu

01:12

to begin the assembly modeling.

01:14

I'm going to convert the right side casing from a body to a component

01:19

in the browser. Right? Click on body 19,

01:21

then select create components from bodies.

01:25

Here's our new component, double click on the name and name it to right casing,

01:29

then press return on the keyboard.

01:32

So here's my new casing component on the model

01:34

and I can click and move it around.

01:37

I want to ground the casing.

01:39

So let's right. Click on right casing in the browser.

01:42

Then choose ground

01:44

the right casing is now grounded and fixed in position.

01:48

So I can now zoom into the mechanics

01:50

and begin to create some movement.

01:53

The reciprocating saw has been designed with a top down approach

01:56

and all the components and parts have been designed in

01:59

context with each other placed in the correct positions.

02:02

This makes assembly modeling the saw mechanics

02:05

much easier because we can use something in fusion

02:08

called as built joints to model all the mechanics,

02:12

abut

02:12

joints are similar to regular joints.

02:15

With the main difference being that as built

02:16

joints maintain the current position of the components.

02:20

So we can only use as built joints if

02:23

our components are already positioned in the correct locations

02:27

to create an as built joint from the toolbar, click assemble,

02:31

then choose as built joint.

02:33

I want to model the movement for this large spur gear

02:36

to rotate around the gear shaft in the center.

02:39

So in the dialogue,

02:41

I choose revolute for joint type,

02:43

I then select the spur gear

02:45

and the gear shaft. Now I need to choose the position for the revolute.

02:49

I'll click to choose this edge here on the gear shaft.

02:53

And fusion provides me with an animation preview of the movement

02:56

and I click OK to confirm the as built joint.

02:60

If I double click on the blue joint symbol,

03:03

I can use my mouse to drive the joint and we can see

03:06

the movement of the spur gear around the shaft is as we want it

03:09

as the spur gear rotates, it turns the crank arm

03:13

with a small rod connected to the spur gear.

03:16

Since the crank arm and the rod are in the correct positions,

03:20

we can use another as built joint to continue the assembly.

03:24

So let's do that and select as built joint from the assembly menu in the toolbar.

03:29

After driving my first joint, I've changed the position of the two components.

03:33

And fusion's asking me whether I want to keep the position that I've

03:36

changed or revert back to the original position of the two components.

03:40

In order to use the as built joint,

03:42

I need to ensure that the components are in the correct position.

03:45

So I won't capture the position of the components and

03:48

I'll click continue to revert back to the original position

03:51

to create the joint. I'll select the crank arm first, then the spur gear.

03:56

Again, our motion is revolute.

03:58

But this time we want the position of the movement here.

04:01

The preview confirms the movement so we can click. OK. In the dialogue

04:06

again, I can use my mouse to drive this joint.

04:08

But this time driving this joint drives both the abut joints in the assembly.

04:13

However, the crank arm isn't moving off the small rod

04:16

and nor is the small rod fixed to the spur wheel.

04:19

So we need to join these parts together

04:22

and we can create a rigid group to do this

04:24

because there's more than one component,

04:26

creating a rigid group is much quicker than creating individual rigid joints.

04:31

For each component

04:32

from the assemble menu.

04:34

Select rigid group, then select the components that you want to group.

04:38

Click the spur gear, join to the small rod,

04:42

the rod clip,

04:43

the small rod bushing

04:45

and then click OK to confirm the rigid group.

04:49

And now when we click to drive the joint,

04:52

all the components move with it

04:57

and we can continue moving our way up through the assembly,

04:60

applying joints and motion to the component parts where necessary.

05:04

And because fusion keeps everything in one single design,

05:07

we can move in and out of workspaces and environments whenever we like

05:11

making modifications to sketches, free form modeling,

05:14

parametric modeling,

05:16

direct modeling

05:17

and of course assembly modeling

05:19

and everything we do is recorded in the timeline.

05:22

So we can go back at any point in our design history

05:25

and make any edits that we need.

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