diff --git a/DentistryHandpieces/TorqueTrendControl.cs b/DentistryHandpieces/TorqueTrendControl.cs
index ff8d183..a4f59ea 100644
--- a/DentistryHandpieces/TorqueTrendControl.cs
+++ b/DentistryHandpieces/TorqueTrendControl.cs
@@ -22,6 +22,7 @@ public sealed class TorqueTrendControl : FrameworkElement
     private const double SensorMaxTorque = 100;
     private const double MinimumTorqueRange = 0.1;
     private const double MinimumSpeedRange = 1;
+    private const double TorqueTrendBinSize = 0.1;
 
     private bool _isManualView;
     private double _viewMinTorque = SensorMinTorque;
@@ -135,10 +136,15 @@ public sealed class TorqueTrendControl : FrameworkElement
         var points = samples
             .Select(sample => ToPlotPoint(sample, plot, minTorque, maxTorque, minSpeed, maxSpeed))
             .ToList();
+        List<TorqueTrendPoint> trendPoints = BuildTrendPoints(samples);
 
         drawingContext.PushClip(new RectangleGeometry(plot));
-        DrawTrajectory(drawingContext, points);
         DrawSamplePoints(drawingContext, points);
+        DrawTrendLine(
+            drawingContext,
+            trendPoints
+                .Select(point => ToPlotPoint(point.Torque, point.Speed, plot, minTorque, maxTorque, minSpeed, maxSpeed))
+                .ToList());
         DrawCurrentPoint(drawingContext, points[^1]);
         drawingContext.Pop();
 
@@ -149,6 +155,16 @@ public sealed class TorqueTrendControl : FrameworkElement
             12,
             Color.FromRgb(15, 118, 110),
             new Point(plot.Left + 6, plot.Top + 5));
+        DrawLegend(drawingContext, plot, trendPoints.Count >= 2);
+        if (trendPoints.Count < 2)
+        {
+            DrawText(
+                drawingContext,
+                "扭矩变化小于传感器精度，暂无有效趋势线",
+                11,
+                Color.FromRgb(180, 83, 9),
+                new Point(plot.Left + 6, plot.Bottom - 38));
+        }
     }
 
     protected override void OnMouseWheel(MouseWheelEventArgs e)
@@ -297,27 +313,58 @@ public sealed class TorqueTrendControl : FrameworkElement
         return new Point(x, y);
     }
 
-    private static void DrawTrajectory(DrawingContext drawingContext, IReadOnlyList<Point> points)
+    private static Point ToPlotPoint(
+        double torque,
+        double speed,
+        Rect plot,
+        double minTorque,
+        double maxTorque,
+        double minSpeed,
+        double maxSpeed)
     {
+        double x = plot.Left + plot.Width * (torque - minTorque) / (maxTorque - minTorque);
+        double y = plot.Bottom - (speed - minSpeed) / (maxSpeed - minSpeed) * plot.Height;
+        return new Point(x, y);
+    }
+
+    private static List<TorqueTrendPoint> BuildTrendPoints(IReadOnlyList<TorqueSamplePayload> samples)
+    {
+        return samples
+            .Where(sample => sample.TorqueMilliNewtonMeters >= SensorMinTorque
+                && sample.TorqueMilliNewtonMeters <= SensorMaxTorque)
+            .GroupBy(sample => Math.Floor(sample.TorqueMilliNewtonMeters / TorqueTrendBinSize))
+            .Select(group => new TorqueTrendPoint(
+                group.Average(sample => sample.TorqueMilliNewtonMeters),
+                group.Average(sample => sample.SpeedRpm)))
+            .OrderBy(point => point.Torque)
+            .ToList();
+    }
+
+    private static void DrawTrendLine(DrawingContext drawingContext, IReadOnlyList<Point> points)
+    {
+        if (points.Count < 2)
+        {
+            return;
+        }
+
         var geometry = new StreamGeometry();
         using (StreamGeometryContext context = geometry.Open())
         {
-            for (int i = 0; i < points.Count; i++)
+            context.BeginFigure(points[0], false, false);
+            for (int i = 1; i < points.Count; i++)
             {
-                if (i == 0)
-                {
-                    context.BeginFigure(points[i], false, false);
-                }
-                else
-                {
-                    context.LineTo(points[i], true, false);
-                }
+                Point previous = points[i - 1];
+                Point current = points[i];
+                double deltaX = current.X - previous.X;
+                var control1 = new Point(previous.X + deltaX / 3, previous.Y);
+                var control2 = new Point(current.X - deltaX / 3, current.Y);
+                context.BezierTo(control1, control2, current, true, false);
             }
         }
 
         geometry.Freeze();
-        var lineBrush = new SolidColorBrush(Color.FromArgb(85, 29, 78, 216));
-        drawingContext.DrawGeometry(null, new Pen(lineBrush, 1.2), geometry);
+        var lineBrush = new SolidColorBrush(Color.FromRgb(15, 118, 110));
+        drawingContext.DrawGeometry(null, new Pen(lineBrush, 2.4), geometry);
     }
 
     private static void DrawSamplePoints(DrawingContext drawingContext, IReadOnlyList<Point> points)
@@ -344,6 +391,23 @@ public sealed class TorqueTrendControl : FrameworkElement
         drawingContext.DrawEllipse(brush, new Pen(Brushes.White, 1.5), point, 5, 5);
     }
 
+    private void DrawLegend(DrawingContext drawingContext, Rect plot, bool hasTrend)
+    {
+        double y = plot.Bottom + 5;
+        var sampleBrush = new SolidColorBrush(Color.FromArgb(175, 29, 78, 216));
+        drawingContext.DrawEllipse(sampleBrush, null, new Point(plot.Left + 116, y + 7), 2.5, 2.5);
+        DrawText(drawingContext, "原始采样点", 10, Color.FromRgb(82, 97, 111), new Point(plot.Left + 122, y));
+
+        if (!hasTrend)
+        {
+            return;
+        }
+
+        var trendPen = new Pen(new SolidColorBrush(Color.FromRgb(15, 118, 110)), 2.4);
+        drawingContext.DrawLine(trendPen, new Point(plot.Left + 194, y + 7), new Point(plot.Left + 214, y + 7));
+        DrawText(drawingContext, "显示趋势线", 10, Color.FromRgb(82, 97, 111), new Point(plot.Left + 220, y));
+    }
+
     private void DrawAxisLabels(
         DrawingContext drawingContext,
         Rect plot,
@@ -485,4 +549,6 @@ public sealed class TorqueTrendControl : FrameworkElement
 
         drawingContext.DrawText(formattedText, origin);
     }
+
+    private readonly record struct TorqueTrendPoint(double Torque, double Speed);
 }