diff --git a/src/main/java/club/joylink/rtss/simulation/cbtc/ATS/data/SortDiagramStation.java b/src/main/java/club/joylink/rtss/simulation/cbtc/ATS/data/SortDiagramStation.java
index a2280d05f..b3553d70f 100644
--- a/src/main/java/club/joylink/rtss/simulation/cbtc/ATS/data/SortDiagramStation.java
+++ b/src/main/java/club/joylink/rtss/simulation/cbtc/ATS/data/SortDiagramStation.java
@@ -46,7 +46,14 @@ public class SortDiagramStation {
 
 
   private Station findNotDepotStation(boolean isRight, int index) {
-    Station station = stationList.get(index);
+    Station station = null;
+    if (index >= stationList.size()) {
+      station = stationList.get(stationList.size() - 1);
+    } else if (index <= 0) {
+      station = stationList.get(0);
+    } else {
+      station = stationList.get(index);
+    }
     while (station.isDepot()) {
       index += isRight ? -1 : 1;
       station = stationList.get(index);