Blender Manikin I

Manikin

"Make your own motion reference"

In this tutorial, we will setup a human-like character for use as reference or constraint target to your rig. You will be able to pose and position this Manikin like you would a real Manikin, and drop it from various heights and onto various obstacles to produce realistic poses as it falls.

Something the animator can import and throw around for reference on how it would look like.

Estimated Time

• 🕐 10 minutes

You will learn

• ✔️ How to apply markers onto rig controls
• ✔️ How to tune the collision shapes of the markers
• ✔️ How to record your simulation back onto the rig controls

Where to find help

If you find or run into any issues with this tutorials, here's what you can do.

• ✔️ Ask in the chat
• ✔️ Ask on the forums

Spelling

There are two ways to spell "Manikin", this tutorial is based on this term here.

• https://www.healthysimulation.com/Manikin/

Bring Your Own Rig

Follow this tutorial either using our provided Manikin rig, or your own character. It can have any number of limbs.

Download Manikin Download Final Scene

Motivation

Why should we even bother simulating a character?

Finding motion reference is one of the most important activities for any animator. And yet I can safely challenge you to find reference for perhaps the most common motion in all blockbuster movies today, something that is either impossible or dangerous for actors or animators alike.

Or how about reference of someone simply falling over, perhaps from heat stroke or staring into the sun.

This is, after all, one of the major reasons for pursuing computer graphics in storytelling rather than real people.

Animators bring life to characters, but of equal challenge is that of lifelessness. Of natural and realistic motion without someone behind the wheel. Be it getting hit or shot, blasted or thrown, animating lifelessness is enough to challenge even the most senior of animators.

As you will find, there is a lot more we can do once our motion reference is in 3D, on our actual character rig within Blender/Maya and infinitely customisable. As opposed to some video on the internet.

Setup

Open your chosen character rig or download the above Manikin rig to get started.

Play around with the controls to get a feel for what we're working with.

FK or IK

Use FK for this tutorial

This Manikin rig has FK and IK (legs) controls, but we will focus on FK controls for this tutorial because it makes simulating much straightforward.

Simulation

The stage is set, now let's apply physics.

Torso

Let's start with the Torso.

1. Select hip_FK
2. Shift select torso_FK
3. Shift select head_FK
4. In Physics Properties panel, run Assign and Connect

This will produce our first Group (named as hip_FK_rGroup, in Ragdoll collection), which is a set of connected Markers.

New Concept

Group

The Group object contains properties that affect all contained markers. It's where you'd edit the overall look and feel of your character, like how stiff it should be and whether or not body parts should collide with each other.

Each Marker can either inherit or otherwise override these values.

Markable Objects

Who can have Marker assigned?

• Mesh objects and
• Pose Bones

Left Arm

Next we will continue from the torso_FK and out into the arms.

1. Select the torso_FK
2. Shift select L_clavicle_FK
3. Shift select L_upperArm_FK
4. Shift select L_lowerArm_FK
5. Shift select L_hand_FK
6. Run Assign and Connect

Is the order important?

Yes, the order in which you select will determine how the markers are connected.

Your first selection is extra important, as it determines whether to start a new group, like for the hip_FK, or to add to an existing group, like the torso_FK.

In this case, we would very much like our arm to be connected to the torso.

Can I skip the clavicles?

Yes, if you have extra controls - such as twist or bend - you can skip these if you don't care to simulate them.

Simply skip over them as you select, from torso_FK directly to L_upperArm_FK.

Right Arm

Now repeat the above process for the other arm.

Legs

Now let's continue down the hips and into the legs.

1. Select the hip_FK
2. Shift select L_thigh_FK
3. Shift select L_knee_FK
4. Shift select L_foot_FK
5. Run Assign and Connect
6. Repeat for the right leg

Drop Test

That's enough setup, let's drop him!

1. Select hip_FK
2. Set Behaviour = Simulated
3. Drop the Manikin a few times

New Concept

Behaviour

Each Marker has a "behaviour", which tells Ragdoll it should interpret the control it has been assigned. Should it fall with gravity? Should it try and match the pose? Should it remain fully animated, even in simulation?

The default behaviour for Assign and Connect is to give the first selection - the "root" - an Animated behaviour.

What does 'Animated'/'Simulated' mean?

Animated means "copy the animation into simulation and make no changes to it"

By instead setting this to Simulated, then Ragdoll will only use the animation for the starting position and orientation of the simulation.

Use Group

Alternatively, you can set it to Use Group to have it use the value of the rGroup node that was created for the whole character.

Tuning

Next let's address the elephant in the room; the shapes. They look awful.

Volumes

The shape of each collider affects your simulation in 2 ways.

• Contact Points
• Rotation Mass

The contact point can be important if your character interacts with an environment or another character. Like in this case where the feet are incorrectly colliding with the ground because of a bad shape.

That's not always the case though, sometimes you just want overlapping motion without contacts in which case the shapes won't matter.

They do however also affect their resistance to rotation. Consider this.

Here, we rotate the exact same shapes, the exact same amount in the exact same amount of time. And yet they respond differently.

This shape has vastly different dimensions in the X, Y and Z directions, resulting in a different rotation mass for each one. As a result, the effort required to rotate it in each axis differs too.

In practice, you'll find this for just about any limb on a character, which is typically longer in one axis. For our Manikin, this is especially true for the default clavicle shapes.

Override Rotate Mass

In some cases, you have a shape but want it to act like a different shape. Rotate Mass is very similar to normal Mass, except in 3 dimensions. Where the position of an object is affected equal in X, Y and Z directions, rotations have 3 separate masses.

Shapes

With this in mind, let's tune some shapes.

1. Select rSolver object, within Ragdoll collection.
2. Activate Manipulator tool at the Toolbar

This brings up the Manipulator interface, where you can manipulate shapes using mouse gestures.

Great, now let's turn those hands and feet into boxes.

Translate, Rotate and Scale

Notice I'm using the..

• Middle-Mouse Button to Translate
• CTRL + Middle-Mouse Button to Rotate
• CTRL + Left-Mouse Button to Scale

The help text screen-right will help you remember these.

Greater Value Step

While dragging the value on Manipulator UI panel, you may hold Shift to increase value changing step.

Symmetry

Also notice the edits are symmetrical; even when they don't start out that way like the feet!

Recording

That's all there is for setting up your character rig for simulation! Let's now transfer the simulation back onto the rig.

1. Run Record Simulation
2. Enjoy

Recording options?

By holding Ctrl while clicking Record Simulation, a dialog pops up provides you more control over recording process.

Start Again

The simulation was recorded into the NLA Track of each marker assigned object with Solo enabled for playback. To start over, disable Solo mode for those tracks (or delete them).

Initial Key

By default, Ragdoll adds one keyframe on the simulation starting frame, this is to keep original pose intact after playback recorded animation.

Auto Cache

If you have recording option Auto Cache enabled while recording, solver will remember simulation result after recorded, which can be helpful if you wish to compare the simulation against baked result. If so, don't forget to turn it off before next simulation.

Next Steps

In the next tutorial, we'll take this a bit further. As you play around with the Rotate Stiffness on either the rGroup or individual rMarker nodes, you'll find some limbs start to misbehave. Especially the knees and elbows, that normally won't allow rotations past a certain angle in a real human (or Manikin for that matter!). That isn't the case here, because we've left out a critical part of any complete ragdoll.

• Full Ragdoll

See you there!