diff --git a/solar_tracking.ic10 b/solar_tracking.ic10
index 7bc8898..4c6dd8a 100644
--- a/solar_tracking.ic10
+++ b/solar_tracking.ic10
@@ -7,7 +7,7 @@ l r0 sensor Horizontal
 sb Solar Horizontal r0
 
 l r1 sensor Vertical
-add r0 r0 90
+add r1 r1 90
 
 sb Solar Vertical r1