Source: Roblox Creator Hub · CC BY 4.0 · View source · Code samples: MIT Imported 2026-10-03. Formatting adapted for this site.
AlignPosition
Inherits from: Constraint → Instance → Object
The AlignPosition constraint applies force to move two attachments together, or to move one attachment to a goal position. As indicated by the name, it only affects the position of the attachments, not their orientation (to align attachments by orientation, see AlignOrientation).
When configuring this constraint, it may be helpful to study Roblox Units to understand how Roblox units compare to metric units.
Force Location
By default, force is applied to the parent of Attachment0 at that attachment's location, meaning that if the parent's center of mass is not aligned with the direction of the force, torque will be applied as well as force. Alternatively, force can be applied to the parents' center of mass by toggling on ApplyAtCenterOfMass.
Reactionary Force
By default, the constraint only applies force to Attachment0 while Attachment1 remains unaffected. If desired, force can be applied to both attachments in equal and opposite directions by enabling ReactionForceEnabled.
Force Limits
You can configure this constraint to apply the maximum force that constraints allow through the RigidityEnabled property. When true, the physics solver reacts as quickly as possible to complete the alignment. When false, the force applied by the constraint is limited based on ForceLimitMode, MaxVelocity, and Responsiveness. See ForceLimitMode for further details.
Attachment Mode
This constraint can use either one or two attachments in calculating its goal. See Mode for details.
Inherits from: Constraint
Memory category: BaseParts
Properties
| Name | Type / Returns | Description |
|---|---|---|
| AlignPosition.ApplyAtCenterOfMass | boolean | Whether force is applied to the parent of Attachment0 at that attachment's location, or at the parents' center of mass. |
| AlignPosition.ForceLimitMode | ForceLimitMode | Determines how the constraint force will be limited. Only used if RigidityEnabled is false. |
| AlignPosition.ForceRelativeTo | ActuatorRelativeTo | Determines the axes that the constraint uses to limit the force. Only applies when RigidityEnabled is false and AlignPosition.ForceLimitMode is PerAxis. . |
| AlignPosition.MaxAxesForce | Vector3 | Maximum force along each axis that the constraint can apply to achieve its goal. |
| AlignPosition.MaxForce | float | Maximum force magnitude the constraint can apply to achieve its goal. |
| AlignPosition.MaxVelocity | float | Maximum speed the attachments can move when converging. |
| AlignPosition.Mode | PositionAlignmentMode | Whether the constraint uses one or two attachments in calculating its goal. |
| AlignPosition.Position | Vector3 | The position to which the constraint should move its Attachment0. |
| AlignPosition.ReactionForceEnabled | boolean | Whether the constraint applies force only to Attachment0, or to both attachments in equal and opposite directions. |
| AlignPosition.Responsiveness | float | Controls how quickly the constraint reaches its goal. Higher values cause the attachment(s) to align more rapidly. |
| AlignPosition.RigidityEnabled | boolean | Whether force is dependent on other properties, or if the physics solver reacts as quickly as possible to complete the alignment. |
Inherited from Constraint
| Name | Type / Returns | Description |
|---|---|---|
| Constraint.Active | boolean | Indicates if the constraint is currently active in the world. |
| Constraint.Attachment0 | Attachment | The Attachment that is connected to Constraint.Attachment1. |
| Constraint.Attachment1 | Attachment | The Attachment that is connected to Constraint.Attachment0. |
| Constraint.Color | BrickColor | The color of the constraint. |
| Constraint.Enabled | boolean | Toggles whether or not the constraint is enabled. |
| Constraint.Visible | boolean | Toggles the constraint's visibility. |
Inherited from Instance
| Name | Type / Returns | Description |
|---|---|---|
| Instance.Archivable | boolean | Determines if an Instance and its descendants can be cloned using Instance:Clone(), and can be saved/published. |
| Instance.archivable | boolean | |
| Instance.Capabilities | SecurityCapabilities | The set of capabilities allowed to be used for scripts inside this container. |
| Instance.IsInSandbox | boolean | Indicates whether the instance is inside a sandboxed container. |
| Instance.Name | string | A non-unique identifier of the Instance. |
| Instance.Parent | Instance | Determines the hierarchical parent of the Instance. |
| Instance.PredictionMode | PredictionMode | Reflects the client-side prediction mode applied to the instance under server-authoritative physics. |
| Instance.RobloxLocked | boolean | A deprecated property that used to protect CoreGui objects. |
| Instance.Sandboxed | boolean | When enabled, the instance can only access abilities in its Capabilities list. |
| Instance.UniqueId | UniqueId | A unique identifier for the instance. |
Inherited from Object
| Name | Type / Returns | Description |
|---|---|---|
| Object.ClassName | string | A read-only string representing the class this Object belongs to. |
| Object.className | string |
AlignPosition.ApplyAtCenterOfMass
When false (default), force is applied to the parent of Attachment0 at that attachment's location, meaning that if the parent's center of mass is not aligned with the direction of the force, torque will be applied as well as force. When true, force is applied at the parents' center of mass.
| Field | Value |
|---|---|
| type | boolean |
| security | {"read":"None","write":"None"} |
| thread safety | ReadSafe |
| category | AlignPosition |
| serialization | {"can_load":true,"can_save":true} |
| capabilities | ["Physics"] |
| simulationAccess | true |
AlignPosition.ForceLimitMode
Determines how the constraint force will be limited when RigidityEnabled is false. When set to Magnitude, the constraint force will be limited such that the magnitude is less than MaxForce. When set to PerAxis, the constraint force along each axis will be limited by MaxAxesForce. The axes along which the force will be limited are based on the ForceRelativeTo property.
| Field | Value |
|---|---|
| type | ForceLimitMode |
| security | {"read":"None","write":"None"} |
| thread safety | ReadSafe |
| category | Compliance |
| serialization | {"can_load":true,"can_save":true} |
| capabilities | ["Physics"] |
| simulationAccess | true |
AlignPosition.ForceRelativeTo
Determines the axes that the constraint uses to limit the force. Only applies when RigidityEnabled is false and AlignPosition.ForceLimitMode is PerAxis. When set to World, the constraint force is computed in the world reference frame and the force limits specified in MaxAxesForce refer to the axes of the world coordinate system. When set to Attachment0 or Attachment1, the force limits specified in MaxAxesForce refer to the axes of the specified attachment coordinate system.
| Field | Value |
|---|---|
| type | ActuatorRelativeTo |
| security | {"read":"None","write":"None"} |
| thread safety | ReadSafe |
| category | Compliance |
| serialization | {"can_load":true,"can_save":true} |
| capabilities | ["Physics"] |
| simulationAccess | true |
AlignPosition.MaxAxesForce
Maximum force along each axis that the constraint can apply to achieve its goal. Only used if RigidityEnabled is false and ForceLimitMode is PerAxis. The axes used to apply to the limit are specified using the ForceRelativeTo property.
| Field | Value |
|---|---|
| type | Vector3 |
| security | {"read":"None","write":"None"} |
| thread safety | ReadSafe |
| category | Compliance |
| serialization | {"can_load":true,"can_save":true} |
| capabilities | ["Physics"] |
| simulationAccess | true |
AlignPosition.MaxForce
Maximum force magnitude the constraint can apply to achieve its goal. Only used if RigidityEnabled is false and ForceLimitMode is Magnitude.
Note that MaxForce, as well as MaxVelocity, are caps to the force and velocity respectively. The actual scale is determined by Responsiveness.
| Field | Value |
|---|---|
| type | float |
| security | {"read":"None","write":"None"} |
| thread safety | ReadSafe |
| category | Compliance |
| serialization | {"can_load":true,"can_save":true} |
| capabilities | ["Physics"] |
| simulationAccess | true |
AlignPosition.MaxVelocity
Maximum speed the attachments can move when converging. Only used if RigidityEnabled is false.
Note that MaxVelocity, as well as MaxForce, are caps to the velocity and force respectively. The actual scale is determined by Responsiveness.
| Field | Value |
|---|---|
| type | float |
| security | {"read":"None","write":"None"} |
| thread safety | ReadSafe |
| category | Compliance |
| serialization | {"can_load":true,"can_save":true} |
| capabilities | ["Physics"] |
| simulationAccess | true |
AlignPosition.Mode
Whether the constraint uses one or two attachments in calculating its goal. By default, this is TwoAttachment, meaning that the constraint disregards Position and attempts to move Attachment0 to the position of Attachment1.
If set to OneAttachment, the constraint disregards Attachment1 and attempts to move Attachment0 to Position.
| Field | Value |
|---|---|
| type | PositionAlignmentMode |
| security | {"read":"None","write":"None"} |
| thread safety | ReadSafe |
| category | AlignmentMode |
| serialization | {"can_load":true,"can_save":true} |
| capabilities | ["Physics"] |
| simulationAccess | true |
AlignPosition.Position
The position to which the constraint should move its Attachment0. Only used if Mode is set to OneAttachment, in which case Attachment1 is disregarded.
| Field | Value |
|---|---|
| type | Vector3 |
| security | {"read":"None","write":"None"} |
| thread safety | ReadSafe |
| category | AlignPosition |
| serialization | {"can_load":true,"can_save":true} |
| capabilities | ["Physics"] |
| simulationAccess | true |
AlignPosition.ReactionForceEnabled
If false (default), the constraint only applies force to Attachment0 while Attachment1 remains unaffected. If true, the constraint applies force to both attachments in equal and opposite directions.
| Field | Value |
|---|---|
| type | boolean |
| security | {"read":"None","write":"None"} |
| thread safety | ReadSafe |
| category | AlignPosition |
| serialization | {"can_load":true,"can_save":true} |
| capabilities | ["Physics"] |
| simulationAccess | true |
AlignPosition.Responsiveness
Controls how quickly the constraint reaches its goal. Higher values cause the attachment(s) to align more rapidly. Value can be between 5 and 200.
| Field | Value |
|---|---|
| type | float |
| security | {"read":"None","write":"None"} |
| thread safety | ReadSafe |
| category | Compliance |
| serialization | {"can_load":true,"can_save":true} |
| capabilities | ["Physics"] |
| simulationAccess | true |
AlignPosition.RigidityEnabled
Whether force is dependent on other properties, or if the physics solver reacts as quickly as possible to complete the alignment. If false (default), the force is determined by MaxForce, MaxVelocity, and Responsiveness. If true, the physics solver reacts as quickly as possible to complete the alignment.
| Field | Value |
|---|---|
| type | boolean |
| security | {"read":"None","write":"None"} |
| thread safety | ReadSafe |
| category | AlignPosition |
| serialization | {"can_load":true,"can_save":true} |
| capabilities | ["Physics"] |
| simulationAccess | true |
Methods
Inherited from Constraint
| Name | Type / Returns | Description |
|---|---|---|
| Constraint:GetDebugAppliedForce | Vector3 | |
| Constraint:GetDebugAppliedTorque | Vector3 |
Inherited from Instance
| Name | Type / Returns | Description |
|---|---|---|
| Instance:AddTag | () | Applies a tag to the instance. |
| Instance:children | Instances | Returns an array of the object's children. |
| Instance:ClearAllChildren | () | This method destroys all of an instance's children. |
| Instance:Clone | Instance | Create a copy of an instance and all its descendants, ignoring instances that are not Archivable. |
| Instance:clone | Instance | |
| Instance:Destroy | () | Sets the Instance.Parent property to nil, locks the Instance.Parent property, disconnects all connections, and calls Destroy() on all children. |
| Instance:destroy | () | |
| Instance:FindFirstAncestor | Instance? | Returns the first ancestor of the Instance whose Instance.Name is equal to the given name. |
| Instance:FindFirstAncestorOfClass | Instance? | Returns the first ancestor of the Instance whose Object.ClassName is equal to the given className. |
| Instance:FindFirstAncestorWhichIsA | Instance? | Returns the first ancestor of the Instance for whom Object:IsA() returns true for the given className. |
| Instance:FindFirstChild | Instance? | Returns the first child of the Instance found with the given name. |
| Instance:findFirstChild | Instance | |
| Instance:FindFirstChildOfClass | Instance? | Returns the first child of the Instance whose ClassName is equal to the given class name. |
| Instance:FindFirstChildWhichIsA | Instance? | Returns the first child of the Instance for whom Object:IsA() returns true for the given className. |
| Instance:FindFirstDescendant | Instance? | Returns the first descendant found with the given Instance.Name. |
| Instance:GetActor | Actor? | Returns the Actor associated with the Instance, if any. |
| Instance:GetAttribute | Variant | Returns the value which has been assigned to the given attribute name. |
| Instance:GetAttributeChangedSignal | RBXScriptSignal | Returns an event that fires when the given attribute changes. |
| Instance:GetAttributes | Dictionary | Returns a dictionary of the instance's attributes. |
| Instance:GetChildren | Instances | Returns an array containing all of the instance's children. |
| Instance:getChildren | Instances | |
| Instance:GetDebugId | string | Returns a coded string of the debug ID used internally by Roblox. |
| Instance:GetDescendants | Instances | Returns an array containing all of the descendants of the instance. |
| Instance:GetFullName | string | Returns a string describing the instance's ancestry. |
| Instance:GetStyled | Variant | Returns the styled or explicitly modified value of the specified property, or else the default property value if it hasn't been styled/modified. |
| Instance:GetStyledPropertyChangedSignal | RBXScriptSignal | Returns an event that fires when the given style property changes on the instance. |
| Instance:GetTags | Array | Gets an array of all tags applied to the instance. |
| Instance:HasTag | boolean | Check whether the instance has a given tag. |
| Instance:IsAncestorOf | boolean | Returns true if an Instance is an ancestor of the given descendant. |
| Instance:IsDescendantOf | boolean | Returns true if an Instance is a descendant of the given ancestor. |
| Instance:isDescendantOf | boolean | |
| Instance:IsPropertyModified | boolean | Returns true if the value stored in the specified property is not equal to the code-instantiated default. |
| Instance:QueryDescendants | Instances | Returns an array containing all descendants of the instance that match the selector string. |
| Instance:Remove | () | Sets the object's Parent to nil, and does the same for all its descendants. |
| Instance:remove | () | |
| Instance:RemoveTag | () | Removes a tag from the instance. |
| Instance:ResetPropertyToDefault | () | Resets a property to its default value. |
| Instance:SetAttribute | () | Sets the attribute with the given name to the given value. |
| Instance:WaitForChild | Instance | Returns the child of the Instance with the given name. If the child does not exist, it will yield the current thread until it does. |
Inherited from Object
| Name | Type / Returns | Description |
|---|---|---|
| Object:GetPropertyChangedSignal | RBXScriptSignal | Get an event that fires when a given property of the object changes. |
| Object:IsA | boolean | Returns true if an object's class matches or inherits from a given class. |
| Object:isA | boolean |
Events
Inherited from Instance
| Name | Type / Returns | Description |
|---|---|---|
| Instance.AncestryChanged | Fires when the Instance.Parent property of this object or one of its ancestors is changed. | |
| Instance.AttributeChanged | Fires whenever an attribute is changed on the Instance. | |
| Instance.ChildAdded | Fires after an object is parented to this Instance. | |
| Instance.childAdded | ||
| Instance.ChildRemoved | Fires after a child is removed from this Instance. | |
| Instance.DescendantAdded | Fires after a descendant is added to the Instance. | |
| Instance.DescendantRemoving | Fires immediately before a descendant of the Instance is removed. | |
| Instance.Destroying | Fires immediately before (or is deferred until after) the instance is destroyed via Instance:Destroy(). | |
| Instance.StyledPropertiesChanged | Fires whenever any style property is changed on the instance, including when a property is set to nil. |
Inherited from Object
| Name | Type / Returns | Description |
|---|---|---|
| Object.Changed | Fires immediately after a property of the object changes, with some limitations. |