diff --git a/.obsidian/workspace.json b/.obsidian/workspace.json
index 15e2b92..f8b1982 100644
--- a/.obsidian/workspace.json
+++ b/.obsidian/workspace.json
@@ -13,14 +13,14 @@
             "state": {
               "type": "pdf",
               "state": {
-                "file": "HCIW/slides/3b Haptic slides.pdf",
+                "file": "HCIW/slides/4 HUI2016-6-forcefeedback.pdf",
                 "page": 1,
                 "left": -14,
                 "top": 544,
                 "zoom": 1.0802083333333334
               },
               "icon": "lucide-file-text",
-              "title": "3b Haptic slides"
+              "title": "4 HUI2016-6-forcefeedback"
             }
           }
         ]
@@ -197,8 +197,9 @@
   },
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   "lastOpenFiles": [
-    "HCIW/slides/3Haptic interaction.pdf",
     "HCIW/slides/3b Haptic slides.pdf",
+    "HCIW/slides/4 HUI2016-6-forcefeedback.pdf",
+    "HCIW/slides/3Haptic interaction.pdf",
     "HCIW/slides/2 Beacon based interfaces.pdf",
     "HCIW/slides/1 User Experience for IoT.pdf",
     "HCIW/slides/1 Interface and Interaction for IoT.pdf",
@@ -224,7 +225,6 @@
     "HCIW/notes",
     "Concurrent Systems/notes/images/Pasted image 20250304082459.png",
     "HCIW/slides",
-    "HCIW",
     "Concurrent Systems/notes/images/Pasted image 20250304093223.png",
     "Concurrent Systems/notes/images/Pasted image 20250304090219.png",
     "Concurrent Systems/notes/images/Pasted image 20250304090207.png",
diff --git a/HCIW/slides/4 HUI2016-6-forcefeedback.pdf b/HCIW/slides/4 HUI2016-6-forcefeedback.pdf
new file mode 100644
index 0000000..d202c10
Binary files /dev/null and b/HCIW/slides/4 HUI2016-6-forcefeedback.pdf differ