diff --git a/Project.toml b/Project.toml
index 6a7edd0..0012854 100644
--- a/Project.toml
+++ b/Project.toml
@@ -23,5 +23,5 @@ ForwardDiff = "0.10"
 Parameters = "0.12"
 RobotDynamics = "0.3.1 - 0.3.1"
 StaticArrays = "1.0"
-TrajectoryOptimization = "0.4.1 - 0.4.1"
+TrajectoryOptimization = "0.4.1 - 0.4.1, 0.5"
 julia = "1"