diff --git a/lib/services/sensor_fusion_service.dart b/lib/services/sensor_fusion_service.dart
index 825806d..7dc908b 100644
--- a/lib/services/sensor_fusion_service.dart
+++ b/lib/services/sensor_fusion_service.dart
@@ -74,13 +74,13 @@ class SensorFusionService {
       final gy = event.y * (180.0 / math.pi);
       
       _currentPitch += gx * dt;
-      _currentRoll += gy * dt;
+      _currentRoll -= gy * dt;
     });
 
     _accelSub = accelerometerEventStream(samplingPeriod: const Duration(milliseconds: 20)).listen((AccelerometerEvent event) {
       // Calculate roll/pitch from accelerometer (accounting for gravity)
       // Assuming phone is mounted roughly vertical or horizontal, we calculate basic roll
-      final accelRoll = math.atan2(event.x, math.sqrt(event.y * event.y + event.z * event.z)) * (180.0 / math.pi);
+      final accelRoll = -math.atan2(event.x, math.sqrt(event.y * event.y + event.z * event.z)) * (180.0 / math.pi);
       final accelPitch = math.atan2(-event.y, event.z) * (180.0 / math.pi);
 
       // Complementary filter: Combine integrated gyro with absolute accel