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Source: Roblox Creator Hub · CC BY 4.0 · View source · Code samples: MIT Imported 2026-10-03. Formatting adapted for this site.

SensorBase

Inherits from: Instance → Object

A SensorBase is an instance that, when parented to a BasePart, outputs additional data about the world around that part. Often, other systems will consume the sensor's output data.

Inherits from: Instance

Descendants: AtmosphereSensor, BuoyancySensor, ControllerSensor, FluidForceSensor

Memory category: Instances

Tags: NotCreatable

Properties

NameType / ReturnsDescription
SensorBase.UpdateTypeSensorUpdateTypeDetermines how the sensor will update its output data.

Inherited from Instance

NameType / ReturnsDescription
Instance.ArchivablebooleanDetermines if an Instance and its descendants can be cloned using Instance:Clone(), and can be saved/published.
Instance.archivableboolean
Instance.CapabilitiesSecurityCapabilitiesThe set of capabilities allowed to be used for scripts inside this container.
Instance.IsInSandboxbooleanIndicates whether the instance is inside a sandboxed container.
Instance.NamestringA non-unique identifier of the Instance.
Instance.ParentInstanceDetermines the hierarchical parent of the Instance.
Instance.PredictionModePredictionModeReflects the client-side prediction mode applied to the instance under server-authoritative physics.
Instance.RobloxLockedbooleanA deprecated property that used to protect CoreGui objects.
Instance.SandboxedbooleanWhen enabled, the instance can only access abilities in its Capabilities list.
Instance.UniqueIdUniqueIdA unique identifier for the instance.

Inherited from Object

NameType / ReturnsDescription
Object.ClassNamestringA read-only string representing the class this Object belongs to.
Object.classNamestring

SensorBase.UpdateType

Determines how the sensor will update its output data.

With SensorUpdateType.OnRead, internal sensor logic is run so that the output properties are always up to date. In this mode, the sensor will only run if you read the properties and they are currently outdated.

With SensorUpdateType.Manual, the output properties will never change. Instead, you can write your own scripts to set the output properties as you like.

FieldValue
typeSensorUpdateType
security{"read":"None","write":"None"}
thread safetyReadSafe
categorySettings
serialization{"can_load":true,"can_save":true}
simulationAccesstrue

Methods

NameType / ReturnsDescription
SensorBase:Sense()Recomputes the sensor's output properties immediately.

Inherited from Instance

NameType / ReturnsDescription
Instance:AddTag()Applies a tag to the instance.
Instance:childrenInstancesReturns an array of the object's children.
Instance:ClearAllChildren()This method destroys all of an instance's children.
Instance:CloneInstanceCreate a copy of an instance and all its descendants, ignoring instances that are not Archivable.
Instance:cloneInstance
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:FindFirstAncestorInstance?Returns the first ancestor of the Instance whose Instance.Name is equal to the given name.
Instance:FindFirstAncestorOfClassInstance?Returns the first ancestor of the Instance whose Object.ClassName is equal to the given className.
Instance:FindFirstAncestorWhichIsAInstance?Returns the first ancestor of the Instance for whom Object:IsA() returns true for the given className.
Instance:FindFirstChildInstance?Returns the first child of the Instance found with the given name.
Instance:findFirstChildInstance
Instance:FindFirstChildOfClassInstance?Returns the first child of the Instance whose ClassName is equal to the given class name.
Instance:FindFirstChildWhichIsAInstance?Returns the first child of the Instance for whom Object:IsA() returns true for the given className.
Instance:FindFirstDescendantInstance?Returns the first descendant found with the given Instance.Name.
Instance:GetActorActor?Returns the Actor associated with the Instance, if any.
Instance:GetAttributeVariantReturns the value which has been assigned to the given attribute name.
Instance:GetAttributeChangedSignalRBXScriptSignalReturns an event that fires when the given attribute changes.
Instance:GetAttributesDictionaryReturns a dictionary of the instance's attributes.
Instance:GetChildrenInstancesReturns an array containing all of the instance's children.
Instance:getChildrenInstances
Instance:GetDebugIdstringReturns a coded string of the debug ID used internally by Roblox.
Instance:GetDescendantsInstancesReturns an array containing all of the descendants of the instance.
Instance:GetFullNamestringReturns a string describing the instance's ancestry.
Instance:GetStyledVariantReturns the styled or explicitly modified value of the specified property, or else the default property value if it hasn't been styled/modified.
Instance:GetStyledPropertyChangedSignalRBXScriptSignalReturns an event that fires when the given style property changes on the instance.
Instance:GetTagsArrayGets an array of all tags applied to the instance.
Instance:HasTagbooleanCheck whether the instance has a given tag.
Instance:IsAncestorOfbooleanReturns true if an Instance is an ancestor of the given descendant.
Instance:IsDescendantOfbooleanReturns true if an Instance is a descendant of the given ancestor.
Instance:isDescendantOfboolean
Instance:IsPropertyModifiedbooleanReturns true if the value stored in the specified property is not equal to the code-instantiated default.
Instance:QueryDescendantsInstancesReturns 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:WaitForChildInstanceReturns 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

NameType / ReturnsDescription
Object:GetPropertyChangedSignalRBXScriptSignalGet an event that fires when a given property of the object changes.
Object:IsAbooleanReturns true if an object's class matches or inherits from a given class.
Object:isAboolean

SensorBase:Sense

Deprecated. This method should not be used in new work.

Recomputes the sensor's output properties immediately.

This method is deprecated and should not be used in new work. When UpdateType is SensorUpdateType.OnRead (the default), the sensor recalculates its output properties automatically the next time you read them, so calling this method is unnecessary. When UpdateType is SensorUpdateType.Manual, the outputs are never recomputed automatically; set the output properties yourself rather than calling this method.

Returns

TypeDescription
()
FieldValue
tags["Deprecated"]
securityNone
thread safetyUnsafe

Events

NameType / ReturnsDescription
SensorBase.OnSensorOutputChangedFires when one of the sensor's output properties changes value.

Inherited from Instance

NameType / ReturnsDescription
Instance.AncestryChangedFires when the Instance.Parent property of this object or one of its ancestors is changed.
Instance.AttributeChangedFires whenever an attribute is changed on the Instance.
Instance.ChildAddedFires after an object is parented to this Instance.
Instance.childAdded
Instance.ChildRemovedFires after a child is removed from this Instance.
Instance.DescendantAddedFires after a descendant is added to the Instance.
Instance.DescendantRemovingFires immediately before a descendant of the Instance is removed.
Instance.DestroyingFires immediately before (or is deferred until after) the instance is destroyed via Instance:Destroy().
Instance.StyledPropertiesChangedFires whenever any style property is changed on the instance, including when a property is set to nil.

Inherited from Object

NameType / ReturnsDescription
Object.ChangedFires immediately after a property of the object changes, with some limitations.

SensorBase.OnSensorOutputChanged

Fires when one of the sensor's output properties changes value. The event carries no arguments; read the relevant output property to get its new value.

A sensor only recomputes its outputs while UpdateType is SensorUpdateType.OnRead (the default), so with the default update type this event fires as the outputs are recalculated on read. When UpdateType is SensorUpdateType.Manual, the outputs — and therefore this event — change only when you set the output properties yourself.

FieldValue
securityNone