Created zeroing constants for new zeroing methods.

Change-Id: I9c4ea481146a2cff1b9b474ba5035de7c9af6d25
diff --git a/frc971/constants.h b/frc971/constants.h
index ad3ce71..0da9c96 100644
--- a/frc971/constants.h
+++ b/frc971/constants.h
@@ -16,6 +16,19 @@
   double allowable_encoder_error;
 };
 
+struct EncoderPlusIndexZeroingConstants {
+  // The amount of index pulses in the limb's range of motion.
+  int num_index_pulses;
+};
+
+struct PotAndAbsoluteEncoderZeroingConstants {
+  // The distance that the absolute encoder needs to complete a full rotation.
+  double abs_duration;
+  // Sample mechanism angle and absolute encoder value.
+  double sample_abs_value;
+  double sample_degrees;
+};
+
 // Defines a range of motion for a subsystem.
 // These are all absolute positions in scaled units.
 struct Range {