Added short description to "What was measured?" part

README.md

@@ -1,10 +1,26 @@
 # March 2025 Chicken-Zucchini Experiments
 ## What was measured?
+The acoustic and vibrational signals recorded by a needle-mounted microphone during 
+Dobot MG400 controlled insertions at three constant speeds through two layered phantom configurations:
+
+- **Phantom 1 (chicken over zucchini):**  
+  - Chicken layer: ~1.95–2.00 cm  
+  - Zucchini layer: ~1.96–2.00 cm  
+  - Gel base: ~2.00 cm
+  - Total insertion depth: 6.5 cm (Dobot Z: –20 mm to –85 mm)
+
+- **Phantom 2 (zucchini over chicken):**  
+  - Zucchini layer: ~2.35–2.50 cm  
+  - Chicken layer: ~1.90–2.30 cm  
+  - Gel base: ~1.50 cm
+  - Total insertion depth: 7.0 cm (Dobot Z: –20 mm to –90 mm)
+
+In both setups, the needle tip was initially positioned 0.5 cm above the phantom surface.
 
 ## Methods
 Type of needle: 22G quincke bevel needle
 
-Measurements were taken using Dobot robot. 
+Measurements were taken using Dobot Mg400 robot arm. 
 
 ### Needle Speeds
 3 different speeds were used.