diff --git a/selfdrive/controls/lib/longitudinal_planner.py b/selfdrive/controls/lib/longitudinal_planner.py
index 37efa4a632..9f7c0016b5 100755
--- a/selfdrive/controls/lib/longitudinal_planner.py
+++ b/selfdrive/controls/lib/longitudinal_planner.py
@@ -121,7 +121,7 @@ class Planner():
 
     # Interpolate 0.05 seconds and save as starting point for next iteration
     a_prev = self.a_desired
-    self.a_desired = np.interp(DT_MDL, T_IDXS[:CONTROL_N], self.a_desired_trajectory)
+    self.a_desired = float(interp(DT_MDL, T_IDXS[:CONTROL_N], self.a_desired_trajectory))
     self.v_desired = self.v_desired + DT_MDL * (self.a_desired + a_prev)/2.0
 
   def publish(self, sm, pm):
diff --git a/selfdrive/modeld/constants.py b/selfdrive/modeld/constants.py
index aa21cd9106..794e3b37d4 100644
--- a/selfdrive/modeld/constants.py
+++ b/selfdrive/modeld/constants.py
@@ -1,8 +1,7 @@
-import numpy as np
 IDX_N = 33
 
 def index_function(idx, max_val=192):
   return (max_val/1024)*(idx**2)
 
 
-T_IDXS = np.array([index_function(idx, max_val=10.0) for idx in range(IDX_N)], dtype=np.float64)
+T_IDXS = [index_function(idx, max_val=10.0) for idx in range(IDX_N)]