Last reviewed 31 Jul 2026

Trigger Paired Avatar Animations with Contacts

Two compatible avatars can use matching Contact Sender and Contact Receiver tags to activate an animation. The receiver writes an Animator parameter when the matching contact enters its volume, and that parameter controls the avatar's animation state.

This setup adds a user-controlled opt-in toggle. The pose only activates when the wearer enables Pair Animation and the matching contact is present.

Video Walkthrough

Use akalink's video for the Unity demonstration, then compare the project against the current component and Animator fields below.

Creator: akalink
Video: VRChat Avatar Dynamics Tutorial: Couples Animations

How the Pair Trigger Works

Avatar A: Contact Sender
  Collision Tag = PairPoseDemo
              │
              │ matching volume overlap
              ▼
Avatar B: Contact Receiver
  Collision Tag = PairPoseDemo
  Parameter     = PairContact
              │
              ▼
Action Animator
  PairModeEnabled = true
  PairContact     = true
              │
              ▼
Paired pose animation

For a reciprocal interaction, each avatar needs both roles: a Sender that the other avatar can detect and a Receiver that drives its own animation.

Avatar	Component	Result
Avatar A	Sender A + Receiver A	Signals Avatar B and controls Avatar A's pose
Avatar B	Sender B + Receiver B	Signals Avatar A and controls Avatar B's pose

Contacts detect volume overlap and set parameters. They do not align the two player positions, rotate players toward each other, or synchronize the timing of two separate animation clips. Build both clips around a known relative position and expect manual alignment in the instance.

Plan the Two Parameters

Use one synced opt-in parameter and one receiver-driven parameter:

Parameter	Type	Where it is defined	Purpose
PairModeEnabled	Bool	FX/Action Animator and VRC Expression Parameters	Wearer's menu-controlled permission
PairContact	Bool	Action Animator only	Contact Receiver output

A Contact Receiver parameter does not need to be added to the VRC Expression Parameters asset. The menu toggle does need an Expression Parameters entry because the Expressions Menu controls it.

PairModeEnabled uses one bit of synced expression-parameter memory.

Create the Opt-In Menu Toggle

In the avatar's VRC Expression Parameters asset:

1. Add PairModeEnabled.
2. Set its type to Bool.
3. Choose the default value deliberately; false keeps the pair animation disabled when the avatar loads.
4. Leave it synced if other users should see the resulting menu-controlled state consistently.

In the Expressions Menu, add a Toggle control:

Menu field	Value
Name	Pair Animation
Type	Toggle
Parameter	PairModeEnabled
Value	1

This menu control does not trigger the pose by itself. It only allows the contact condition to activate it.

Configure the Contact Sender

Add a VRC Contact Sender to a child GameObject positioned at the intended interaction point.

Sender field	Setup
Root Transform	The transform the volume should follow, or blank to use the component's GameObject
Shape Type	Sphere, Capsule, or Box based on the interaction area
Radius / Height / Size	Fit the visible interaction point without covering unrelated body areas
Position / Rotation	Align the contact volume in the Scene view
Local Only	Off when the sender must participate in the paired avatar interaction
Collision Tags	The shared custom tag, such as PairPoseDemo

Collision tags are case-sensitive. PairPoseDemo and pairposedemo do not match. VRChat allows up to 16 tags on one Contact and recommends PascalCase for custom tags.

Configure the Contact Receiver

Add a VRC Contact Receiver to the partner avatar's corresponding interaction point.

Receiver field	Setup
Root Transform	The transform the receiver volume should follow
Shape Type	Match the required interaction area
Allow Self	Off
Allow Others	On
Local Only	Off for the shared paired-avatar setup
Collision Tags	Exactly the same custom tag as the Sender
Receiver Type	Constant
Parameter	PairContact
Value	1

With Constant, PairContact remains true while at least one matching Sender is present and returns to false when none are detected. This makes the animation exit condition predictable.

Use OnEnter only when the Animator should receive a one-frame pulse. For an animation that should remain active during overlap, Constant is the direct fit.

Build the Action Layer

Use the Action Playable Layer for a full-body pose. VRChat's Action layer is intended for transform animations that override the character, but the layer has zero weight by default. It must be blended up for the pose and back down afterward.

Create these states:

Entry
  └── Pair Idle
        ├── Enable Action Weight
        │      └── Pair Pose
        │              └── Disable Action Weight
        │                      └── Pair Idle
        └────────────────────────────────────────

Pair Idle → Enable Action Weight

Use both transition conditions:

PairModeEnabled == true
PairContact     == true

Disable Has Exit Time. Both conditions must be true at the same time.

Enable Action Weight

Add a VRC Playable Layer Control behavior:

Field	Value
Layer	Action
Goal Weight	1
Blend Duration	Short blend appropriate for the pose

Transition to Pair Pose after the weight state has run.

Pair Pose

Assign the avatar's matching pose clip. The clip should contain only the transforms the pose is meant to control.

Exit to Disable Action Weight when either permission or contact ends. Unity transitions combine multiple conditions with AND, so use two separate exit transitions:

PairModeEnabled == false

PairContact == false

Either transition can leave the pose.

Disable Action Weight

Add another VRC Playable Layer Control:

Field	Value
Layer	Action
Goal Weight	0
Blend Duration	Match the desired release blend

Return to Pair Idle after the layer has blended down.

Control Tracking During the Pose

If the animation must control the head, hands, hip, or feet, add VRC Animator Tracking Control to the pose entry state and set only those body parts to Animation. Add a reset state that returns the same body parts to Tracking when the pose ends.

Tracking Control values persist until another state changes them. Omitting the reset can leave hands or other tracked body parts under animation control after the paired pose has finished.

Body area	Use Animation when	Restore Tracking when
Head	The clip authors the head pose	The paired pose exits
Left / Right Hand	The clip fixes hand placement	The paired pose exits
Hip / Feet	A full-body clip controls them	The paired pose exits
Eyes / Eyelids	The clip intentionally controls them	Normal eye movement should resume
Mouth / Jaw	The clip intentionally suppresses visemes	Normal voice-driven visemes should resume

Align the Pair

The two animation clips need matching reference positions:

1. Author both avatars in the same scene using a shared origin.
2. Place the avatar roots at the intended distance and facing direction.
3. Animate each avatar's pose against that fixed reference.
4. Position the Sender and Receiver volumes where the two avatars meet.
5. In VRChat, have both players stand at the authored spacing before enabling the interaction.

Do not animate the avatar root to move the player capsule into position. The contact system supplies a trigger, not player locomotion or a shared constraint.

Test Both Avatars

Run every row with both avatars present:

Test	Expected result
Both toggles off	Neither pose activates
Avatar A enabled, Avatar B disabled	Only Avatar A is eligible to pose
Both enabled but contacts separated	Both remain idle
Matching contacts overlap	Each enabled avatar enters its matching pose
One wearer disables the menu toggle	That avatar exits immediately
Contacts separate	Constant receiver resets and the pose exits
Non-matching custom tag enters	No parameter change
Same avatar touches its own receiver	No activation because Allow Self is off
Pose exits	Action weight returns to zero and tracking returns to Tracking
Third avatar copies the tag	The receiver can match it; the tag is not identity verification

Troubleshooting

Help! The two Contacts overlap but nothing happens.

Compare the Collision Tags character by character because they are case-sensitive. Then confirm the Receiver has Allow Others enabled, uses PairContact, and the Animator contains a Bool parameter with the same name.

Help! The pose activates when I touch my own avatar.

Turn off Allow Self on the Contact Receiver. Keep Allow Others enabled so the partner avatar's Sender can still match it.

Help! Enabling the menu toggle immediately starts the pose.

Check the transition from Pair Idle. It must require both PairModeEnabled == true and PairContact == true, with Has Exit Time disabled.

Help! The animation stops as soon as the Contact enters.

Use the Constant Receiver Type for a pose that should remain active during overlap. OnEnter sets the receiver parameter for one frame and then resets it.

Help! The Action animation is active but has no visible effect.

The Action Playable Layer starts at zero weight. Confirm the entry state runs VRC Playable Layer Control with Action selected and Goal Weight set to 1 before the pose state.

Help! My hands remain locked after the pose ends.

Add a reset state with VRC Animator Tracking Control and return every body part changed by the pose to Tracking. Tracking Control persists until another state changes it.

Help! The avatars animate but do not line up.

Contacts only detect an overlap and set the parameter. Recheck the shared authoring origin, facing direction, root spacing, and the world-space placement players use before activating the pair.

Help! An unexpected avatar can trigger the interaction.

Any Sender with the same custom tag can match the Receiver. Change the shared tag on both intended avatars and keep the opt-in menu toggle off when the wearer does not want the interaction available.

Official VRChat References

• Contacts
• Animator Parameters
• Playable Layers
• State Behaviors
• Expressions Menu and Controls

Continue with Avatar Dynamics

• Use Contact Senders, Receivers, and PhysBone Parameters
• Build Hold-to-Activate Avatar Contacts
• Toggle Avatar Props with a PhysBone Grab Handle
• Test Avatar Dynamics at Four Levels
• Avatar Optimization Checklist
• Avatar Creation Guides

Topics: Contacts, paired animations, Action layer, avatar parameters