diff --git a/application/sources/document.cc b/application/sources/document.cc
index c3d8fab1..8d1a169b 100644
--- a/application/sources/document.cc
+++ b/application/sources/document.cc
@@ -20,6 +20,11 @@
 
 unsigned long Document::m_maxSnapshot = 1000;
 
+Document::Bone::Bone(const dust3d::Uuid& withId)
+{
+    id = withId.isNull() ? dust3d::Uuid::createUuid() : withId;
+}
+
 void Document::Node::setRadius(float toRadius)
 {
     if (toRadius < MeshGenerator::m_minimalRadius)
@@ -2775,3 +2780,33 @@ void Document::collectCutFaceList(std::vector<QString>& cutFaces) const
     for (const auto& it : cutFacePartIdList)
         cutFaces.push_back(QString(it.toString().c_str()));
 }
+
+void Document::addBone(const dust3d::Uuid& boneId)
+{
+    // TODO:
+}
+
+void Document::addNodesToBone(const dust3d::Uuid& boneId, const std::vector<dust3d::Uuid>& nodeIds)
+{
+    // TODO:
+}
+
+void Document::removeNodesFromBone(const dust3d::Uuid& boneId, const std::vector<dust3d::Uuid>& nodeIds)
+{
+    // TODO:
+}
+
+void Document::markNodeAsJointForBone(const dust3d::Uuid& boneId, const dust3d::Uuid& nodeId)
+{
+    // TODO:
+}
+
+void Document::markNodeAsNotJointForBone(const dust3d::Uuid& boneId, const dust3d::Uuid& nodeId)
+{
+    // TODO:
+}
+
+void Document::removeBone(const dust3d::Uuid& boneId)
+{
+    // TODO:
+}
diff --git a/application/sources/document.h b/application/sources/document.h
index 1df5f665..4bdab676 100644
--- a/application/sources/document.h
+++ b/application/sources/document.h
@@ -561,6 +561,15 @@ public:
         std::set<dust3d::Uuid> m_childrenIdSet;
     };
 
+    class Bone {
+    public:
+        dust3d::Uuid id;
+        dust3d::Uuid parentId;
+        std::vector<dust3d::Uuid> childrenIds;
+
+        Bone(const dust3d::Uuid& withId = dust3d::Uuid());
+    };
+
 signals:
     void nodeCutRotationChanged(dust3d::Uuid nodeId);
     void nodeCutFaceChanged(dust3d::Uuid nodeId);
@@ -656,7 +665,9 @@ public: // need initialize
     std::map<dust3d::Uuid, Node> nodeMap;
     std::map<dust3d::Uuid, Edge> edgeMap;
     std::map<dust3d::Uuid, Component> componentMap;
+    std::map<dust3d::Uuid, Bone> boneMap;
     Component rootComponent;
+    Bone rootBone;
 
 public:
     Document();
@@ -851,6 +862,12 @@ public slots:
     void setYlockState(bool locked);
     void setZlockState(bool locked);
     void setRadiusLockState(bool locked);
+    void addBone(const dust3d::Uuid& boneId);
+    void addNodesToBone(const dust3d::Uuid& boneId, const std::vector<dust3d::Uuid>& nodeIds);
+    void removeNodesFromBone(const dust3d::Uuid& boneId, const std::vector<dust3d::Uuid>& nodeIds);
+    void markNodeAsJointForBone(const dust3d::Uuid& boneId, const dust3d::Uuid& nodeId);
+    void markNodeAsNotJointForBone(const dust3d::Uuid& boneId, const dust3d::Uuid& nodeId);
+    void removeBone(const dust3d::Uuid& boneId);
 
 private:
     void resolveSnapshotBoundingBox(const dust3d::Snapshot& snapshot, QRectF* mainProfile, QRectF* sideProfile);