if can not find a path issue

social_mpc/path.py

@@ -69,6 +69,9 @@ class PathPlanner():
             dx=dx,
             coords=(x, y),
             max_distance=self.max_d)
+            
+        if len(xl) == 0 or len(yl) == 0 or len(vxl) == 0 or len(vyl) == 0:
+            return []
         d_angle = np.arctan2(vxl[0], -vyl[0]) - pos[2]
         if dl[0] < self.max_d_orientation:  # if within range, set waypoint = target
             wpt_pos = [self.target[0], self.target[1], self.target[2]]
@@ -142,9 +145,10 @@ class PathPlanner():
                     continue
 
             wpt = self.get_next_waypoint(robot_pose)
-
-            with lock:
-                shared_waypoint[0] = True
-                shared_waypoint[1] = float(wpt[0])
-                shared_waypoint[2] = float(wpt[1])
-                shared_waypoint[3] = float(wpt[2])
+            
+            if wpt:
+                with lock:
+                    shared_waypoint[0] = True
+                    shared_waypoint[1] = float(wpt[0])
+                    shared_waypoint[2] = float(wpt[1])
+                    shared_waypoint[3] = float(wpt[2])
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