diff --git a/control/walle.py b/control/walle.py
index 56ecf38..63a139e 100644
--- a/control/walle.py
+++ b/control/walle.py
@@ -48,10 +48,10 @@ class WallE:
                 velocity_r = sin_angle * force
                 velocity_l = cos_angle * force
         elif cos_angle < 0 and sin_angle > 0:
-            if cos_angle < sin_angle:
+            if abs(cos_angle) < sin_angle:
                 velocity_r = 1 - sin_angle * force
                 velocity_l = sin_angle * force
-            elif cos_angle > abs(sin_angle):
+            elif cos_angle > sin_angle:
                 velocity_r = sin_angle * force
                 velocity_l = cos_angle * force
         else: