Big Trouble In Little Blender – 1.6 Animating a basic spring

Notes made after creating a spring for a game element in my current Unity project. I needed to animate the spring – The notes below provide a method which keeps the scale intact.

These notes probably won’t be useful for anyone other than myself. I’m planning on building models as required, rather than in one lump – Which means I’ll forget everything in the meantime & have to relearn every model I build – To avoid this as much as possible, I’m hoping to use these posts as a reference point.

Apologies for any obvious mistakes or omissions – These notes were made as I was learning, and not necessarily as I had learnt.

 

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In the add modifier section change the value of the ‘Screw‘ field to stretch the spring to the desired maximum height.

next duplicate the spring using tools->duplicate – creating spring #2

Back in the add ‘Modifier Tools‘ section – change the ‘Screw‘ value of this duplicate so the spring #2 is at its minimum desired height – then click ‘Apply‘

Select the original (fully expanded) spring #1 and click ‘Apply‘ in the ‘Add Modifier‘ box

 

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With the original (fully expanded) spring #1 – still selected

select ‘data object data‘ – the triangle icon next to the modifiers screwdriver icon

in the ‘shape keys‘ section of ‘data object data‘

click the + button/icon
this should add an element called ‘Basis‘
storing the settings the original (fully expanded) spring #1

Select the second (fully contracted) spring #2
hold down shift and select the original (fully expanded) spring #1

in the ‘shape keys‘ section of ‘data object data‘
click on the black arrow/triangle (under the ‘add button‘)

this should display a pull down menu
from this menu select ‘join as shapes‘

which will add a second element to the ‘shape keys list‘ – this element will have the name of the second (fully contracted) spring #2 (in this case Vert.001)

Since there no further need for the second (fully contracted) spring #2
this can be hidden (or deleted)

 

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In the ‘shape keys‘ section of ‘data object data‘
click on the name of the second (fully contracted) spring #2 (vert.001)

doing this should expand the ‘data object data‘ section
displaying more the shape keys parameters
(if this doesn’t occur try clicking on the white down arrow on the right hand side of the ‘data object data‘ section

sliding the ‘value‘ parameter up and down should expand and contract the spring.

Value 0 = Maximum

Value 0.5 = Mid

Value 1 = Minimum

 

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To create an animation – Using the animation bar move the green marker to the first frame

in the ‘shape keys‘ section of ‘data object data‘
slide the ‘Value‘ parameter and set the spring to fully coiled

& with the mouse pointer OVER the ‘Value‘ parameter press the I key
this will add a frame to the animation bar & turn the ‘Value‘ field green

in the animation bar move the green marker to the last frame
& with the mouse pointer over the value parameter press the I key

In the animation bar move the green marker to the middle frame

in the ‘shape keys‘ section of ‘data object data‘
slide the ‘Value‘ parameter and set the spring to fully uncoiled
& with the mouse pointer over the value parameter press the I key

Now pressing play – you should have a half decent bouncing spring animation

 

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Next post: 1.7 Initial Unity FBX Import & Animation Notes (Part2)

Last post: 1.5 Creating a basic Spring

Contents page.

 

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Blackadder How did World War 1 Begin

Big Trouble In Little Blender – 1.5 Creating a basic Spring

Notes made after creating a spring for a game element in my current Unity project. The process itself isn’t too complicated & the results are pretty nice.

These notes probably won’t be useful for anyone other than myself. I’m planning on building models as required, rather than in one lump – Which means I’ll forget everything in the meantime & have to relearn every model I build – To avoid this as much as possible, I’m hoping to use these posts as a reference point.

Apologies for any obvious mistakes or omissions – These notes were made as I was learning, and not necessarily as I had learnt.

 

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First the ‘Add Mesh: Extra Objects‘ add-on needs to be enabled – This is used to add a single vertices later in the process.

To do this – goto File->User Preferences

This should open the ‘Blender User Preferences‘ window
From here click Add-On’s tab at the top of the window and search for ‘Extra Objects‘

Add a tick to ‘Add Mesh: Extra Objects‘
& everything is done.

 

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Next add a circle – this circle will be used by blender to create the body of the spring;

Once created – scale the circle to the desired thickness of the spring

since the spring will coil around the XY axis – the circle needs to be rotated by 90 degrees on the x axis

In this example – the spring will be generated/coiled around the central point (position 0, 0, 0).

The radius of the spring will be determined by how far the circle is moved along the x axis

 

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Now to add a single vert – this is used to determine the centre of the spring

Make sure the circle is selected.
Press shift-A to open the add menu
From here select – Mesh->SingleVert->Add Single vert

this will add a single vertices at position 0, 0, 0

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The mesh and circle need to be ‘joined‘ creating a single object;
Go to ‘object mode‘ (bottom half of the screen – right of the Object menu)
right click the circle
hold shift and right click the single vert
this will select both elements at the same time

hold ctrl-J – this will join the two objects
it will also move the axis point to the middle of the world (position 0, 0, 0)

 

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Next the screw tool is used to generate and define the spring – but first it is needed to create a doughnut;

On the right hand side of the screen in the click the spanner icon
this will open the modifiers section

click ‘Add modifier‘

and from the list select ‘Screw‘

this should apply the ‘Screw Modifier‘ to the circle

 

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Construct the spring from the doughnut;

In the ‘Add Modifier‘ ‘Screw‘ settings;

to set the scale of the coil – change the value in the ‘Screw‘ section
this will determine how much the coil rises each 360 degree rotation

set the number of coils – change the value in the ‘Iteration‘ parameter
this will termine the size of the spring – the number of coils used to make up the spring

the steps parameter determines how many angles are used to build each coil
the default is 16 – since I generally work with low poly game elements I’m moving this down to 8

make sure ‘click order‘ option is selected to make sure the spring is drawn nicely

 

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That should create a simple spring.
if thats all you need – click ‘Apply‘ in the modifiers box to set the values chosen & move on (maybe close the ends of the spring?)

if you want to animate the spring – DON’T click ‘Apply‘ quite yet… go to the next post (link below) and continue from there…

 

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Next post: 1.6 Animating a basic spring

Last post: 1.4 Initial Unity FBX Import & Animation Notes (Part1)

Contents page.

 

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Crash Test Dummies – Afternoons & Coffeespoons