try an alternative approach for the grab/release functionality by disabling/enabling physics simulation

Source/SenseGlove/Private/SenseGlove/GameFramework/SGPawn.cpp

@@ -1215,14 +1215,14 @@ bool ASGPawn::IsGrabbing(const USGVirtualHandComponent* Hand, AActor*& OutActor)
     return Hand == HandLeft ? IsLeftHandGrabbing(OutActor) : IsRightHandGrabbing(OutActor);
 }
 
-void ASGPawn::GrabLeft(AActor* Actor)
+void ASGPawn::Grab(USGVirtualHandComponent* Hand, AActor* Actor)
 {
     if (!ensureAlwaysMsgf(IsValid(Actor), TEXT("%s"), TEXT("ERROR: invalid actor!")))
     {
         return;
     }
 
-    const USGGrabComponent* GrabComponent = USGGrabComponent::GetGrabComponent(Actor);
+    const USGGrabComponent* GrabComponent{USGGrabComponent::GetGrabComponent(Actor)};
     if (!GrabComponent)
     {
         return;
@@ -1238,7 +1238,23 @@ void ASGPawn::GrabLeft(AActor* Actor)
     const FName SocketName{GrabComponent->GetAttachmentSocketName()};
     ensureAlwaysMsgf(SocketName != NAME_None, TEXT("invalid attachment socket name!"));
 
-    const bool bAttached = Actor->AttachToComponent(HandLeft, MoveTemp(AttachmentRules), SocketName);
+    const USceneComponent* ActorRootComponent{Cast<USceneComponent>(Actor->GetRootComponent())};
+    if (!ensureAlwaysMsgf(IsValid(ActorRootComponent), TEXT("%s"), TEXT("ERROR: invalid actor's root component!")))
+    {
+        return;
+    }
+    TArray<USceneComponent*> ActorChildrenComponents;
+    ActorRootComponent->GetChildrenComponents(true, ActorChildrenComponents);
+    for (USceneComponent* SceneComponent : ActorChildrenComponents)
+    {
+        UPrimitiveComponent* PrimitiveComponent{Cast<UPrimitiveComponent>(SceneComponent)};
+        if (IsValid(PrimitiveComponent))
+        {
+            PrimitiveComponent->SetSimulatePhysics(false);
+        }
+    }
+
+    const bool bAttached = Actor->AttachToComponent(Hand, MoveTemp(AttachmentRules), SocketName);
     if (bAttached)
     {
         ActorLeftHandGrabbing = Actor;
@@ -1249,40 +1265,6 @@ void ASGPawn::GrabLeft(AActor* Actor)
     }
 }
 
-void ASGPawn::GrabRight(AActor* Actor)
-{
-    if (!ensureAlwaysMsgf(IsValid(Actor), TEXT("%s"), TEXT("ERROR: invalid actor!")))
-    {
-        return;
-    }
-
-    const USGGrabComponent* GrabComponent = USGGrabComponent::GetGrabComponent(Actor);
-    if (!GrabComponent)
-    {
-        return;
-    }
-
-    FAttachmentTransformRules AttachmentRules{
-        FAttachmentTransformRules(GrabComponent->GetAttachmentLocationRule(),
-                                  GrabComponent->GetAttachmentRotationRule(),
-                                  GrabComponent->GetAttachmentScaleRule(),
-                                  GrabComponent->GetAttachmentWeldSimulatedBodies())
-    };
-
-    const FName SocketName{GrabComponent->GetAttachmentSocketName()};
-    ensureAlwaysMsgf(SocketName != NAME_None, TEXT("invalid attachment socket name!"));
-
-    const bool bAttached = Actor->AttachToComponent(HandRight, MoveTemp(AttachmentRules), SocketName);
-    if (bAttached)
-    {
-        ActorRightHandGrabbing = Actor;
-    }
-    else
-    {
-        SGLOG_ERROR("Failed to grab the actor with the right hand!", Actor, SocketName);
-    }
-}
-
 void ASGPawn::ReleaseLeft()
 {
     if (!IsValid(ActorLeftHandGrabbing))
@@ -1290,7 +1272,7 @@ void ASGPawn::ReleaseLeft()
         return;
     }
 
-    const USGGrabComponent* GrabComponent = USGGrabComponent::GetGrabComponent(ActorLeftHandGrabbing);
+    const USGGrabComponent* GrabComponent{USGGrabComponent::GetGrabComponent(ActorLeftHandGrabbing)};
     if (!IsValid(GrabComponent))
     {
         return;
@@ -1303,6 +1285,23 @@ void ASGPawn::ReleaseLeft()
                                   GrabComponent->GetDetachmentInCallModify())
         );
 
+    const UPrimitiveComponent* ActorRootComponent{
+        Cast<UPrimitiveComponent>(ActorLeftHandGrabbing->GetRootComponent())
+    };
+    if (ensureAlwaysMsgf(IsValid(ActorRootComponent), TEXT("%s"), TEXT("ERROR: invalid actor's root component!")))
+    {
+        TArray<USceneComponent*> ActorChildrenComponents;
+        ActorRootComponent->GetChildrenComponents(true, ActorChildrenComponents);
+        for (USceneComponent* SceneComponent : ActorChildrenComponents)
+        {
+            UPrimitiveComponent* PrimitiveComponent{Cast<UPrimitiveComponent>(SceneComponent)};
+            if (IsValid(PrimitiveComponent))
+            {
+                PrimitiveComponent->SetSimulatePhysics(true);
+            }
+        }
+    }
+
     ActorLeftHandGrabbing = nullptr;
 }
 
@@ -1313,7 +1312,7 @@ void ASGPawn::ReleaseRight()
         return;
     }
 
-    const USGGrabComponent* GrabComponent = USGGrabComponent::GetGrabComponent(ActorRightHandGrabbing);
+    const USGGrabComponent* GrabComponent{USGGrabComponent::GetGrabComponent(ActorRightHandGrabbing)};
     if (!IsValid(GrabComponent))
     {
         return;
@@ -1326,6 +1325,23 @@ void ASGPawn::ReleaseRight()
                                   GrabComponent->GetDetachmentInCallModify())
         );
 
+    const UPrimitiveComponent* ActorRootComponent{
+        Cast<UPrimitiveComponent>(ActorLeftHandGrabbing->GetRootComponent())
+    };
+    if (ensureAlwaysMsgf(IsValid(ActorRootComponent), TEXT("%s"), TEXT("ERROR: invalid actor's root component!")))
+    {
+        TArray<USceneComponent*> ActorChildrenComponents;
+        ActorRootComponent->GetChildrenComponents(true, ActorChildrenComponents);
+        for (USceneComponent* SceneComponent : ActorChildrenComponents)
+        {
+            UPrimitiveComponent* PrimitiveComponent{Cast<UPrimitiveComponent>(SceneComponent)};
+            if (IsValid(PrimitiveComponent))
+            {
+                PrimitiveComponent->SetSimulatePhysics(true);
+            }
+        }
+    }
+
     ActorRightHandGrabbing = nullptr;
 }
 

Source/SenseGlove/Private/SenseGlove/GameFramework/SGPlayerController.cpp

@@ -206,7 +206,7 @@ void ASGPlayerController::BeginPlay()
 
     SGPawn->OnGrabStateUpdated().AddWeakLambda(
         this, [=](
-        const USGVirtualHandComponent* Hand,
+        USGVirtualHandComponent* Hand,
         AActor* ActorThumbCanGrab, const AActor* ActorIndexCanGrab,
         const AActor* ActorMiddleCanGrab) -> void
         {

Source/SenseGlove/Public/SenseGlove/GameFramework/SGPawn.h

@@ -55,7 +55,7 @@ class SENSEGLOVE_API ASGPawn : public APawn
 public:
     DECLARE_EVENT_FourParams(
         ASGPawn, FGrabStateUpdatedEvent,
-        const USGVirtualHandComponent*, AActor*, const AActor*, const AActor*);
+        USGVirtualHandComponent*, AActor*, const AActor*, const AActor*);
 
     FGrabStateUpdatedEvent& OnGrabStateUpdated()
     {
@@ -631,15 +631,18 @@ public:
     }
 
 public:
-    void GrabLeft(AActor* Actor);
+    FORCEINLINE void GrabLeft(AActor* Actor)
-
-    void GrabRight(AActor* Actor);
-
-    FORCEINLINE void Grab(const USGVirtualHandComponent* Hand, AActor* Actor)
     {
-        return Hand == HandLeft ? GrabLeft(Actor) : GrabRight(Actor);
+        Grab(HandLeft, Actor);
     }
 
+    FORCEINLINE void GrabRight(AActor* Actor)
+    {
+        Grab(HandRight, Actor);
+    }
+
+    void Grab(USGVirtualHandComponent* Hand, AActor* Actor);
+
     void ReleaseLeft();
 
     void ReleaseRight();