diff --git a/wpilibc/src/main/native/cpp/simulation/RoboRioSim.cpp b/wpilibc/src/main/native/cpp/simulation/RoboRioSim.cpp
index 0c7a88e02b..0d1d104f59 100644
--- a/wpilibc/src/main/native/cpp/simulation/RoboRioSim.cpp
+++ b/wpilibc/src/main/native/cpp/simulation/RoboRioSim.cpp
@@ -39,10 +39,12 @@ std::unique_ptr<CallbackStore> RoboRioSim::RegisterVInVoltageCallback(
   return store;
 }
 
-double RoboRioSim::GetVInVoltage() { return HALSIM_GetRoboRioVInVoltage(); }
+units::volt_t RoboRioSim::GetVInVoltage() {
+  return units::volt_t(HALSIM_GetRoboRioVInVoltage());
+}
 
-void RoboRioSim::SetVInVoltage(double vInVoltage) {
-  HALSIM_SetRoboRioVInVoltage(vInVoltage);
+void RoboRioSim::SetVInVoltage(units::volt_t vInVoltage) {
+  HALSIM_SetRoboRioVInVoltage(vInVoltage.to<double>());
 }
 
 std::unique_ptr<CallbackStore> RoboRioSim::RegisterVInCurrentCallback(
@@ -54,10 +56,12 @@ std::unique_ptr<CallbackStore> RoboRioSim::RegisterVInCurrentCallback(
   return store;
 }
 
-double RoboRioSim::GetVInCurrent() { return HALSIM_GetRoboRioVInCurrent(); }
+units::ampere_t RoboRioSim::GetVInCurrent() {
+  return units::ampere_t(HALSIM_GetRoboRioVInCurrent());
+}
 
-void RoboRioSim::SetVInCurrent(double vInCurrent) {
-  HALSIM_SetRoboRioVInCurrent(vInCurrent);
+void RoboRioSim::SetVInCurrent(units::ampere_t vInCurrent) {
+  HALSIM_SetRoboRioVInCurrent(vInCurrent.to<double>());
 }
 
 std::unique_ptr<CallbackStore> RoboRioSim::RegisterUserVoltage6VCallback(
@@ -69,12 +73,12 @@ std::unique_ptr<CallbackStore> RoboRioSim::RegisterUserVoltage6VCallback(
   return store;
 }
 
-double RoboRioSim::GetUserVoltage6V() {
-  return HALSIM_GetRoboRioUserVoltage6V();
+units::volt_t RoboRioSim::GetUserVoltage6V() {
+  return units::volt_t(HALSIM_GetRoboRioUserVoltage6V());
 }
 
-void RoboRioSim::SetUserVoltage6V(double userVoltage6V) {
-  HALSIM_SetRoboRioUserVoltage6V(userVoltage6V);
+void RoboRioSim::SetUserVoltage6V(units::volt_t userVoltage6V) {
+  HALSIM_SetRoboRioUserVoltage6V(userVoltage6V.to<double>());
 }
 
 std::unique_ptr<CallbackStore> RoboRioSim::RegisterUserCurrent6VCallback(
@@ -86,12 +90,12 @@ std::unique_ptr<CallbackStore> RoboRioSim::RegisterUserCurrent6VCallback(
   return store;
 }
 
-double RoboRioSim::GetUserCurrent6V() {
-  return HALSIM_GetRoboRioUserCurrent6V();
+units::ampere_t RoboRioSim::GetUserCurrent6V() {
+  return units::ampere_t(HALSIM_GetRoboRioUserCurrent6V());
 }
 
-void RoboRioSim::SetUserCurrent6V(double userCurrent6V) {
-  HALSIM_SetRoboRioUserCurrent6V(userCurrent6V);
+void RoboRioSim::SetUserCurrent6V(units::ampere_t userCurrent6V) {
+  HALSIM_SetRoboRioUserCurrent6V(userCurrent6V.to<double>());
 }
 
 std::unique_ptr<CallbackStore> RoboRioSim::RegisterUserActive6VCallback(
@@ -118,12 +122,12 @@ std::unique_ptr<CallbackStore> RoboRioSim::RegisterUserVoltage5VCallback(
   return store;
 }
 
-double RoboRioSim::GetUserVoltage5V() {
-  return HALSIM_GetRoboRioUserVoltage5V();
+units::volt_t RoboRioSim::GetUserVoltage5V() {
+  return units::volt_t(HALSIM_GetRoboRioUserVoltage5V());
 }
 
-void RoboRioSim::SetUserVoltage5V(double userVoltage5V) {
-  HALSIM_SetRoboRioUserVoltage5V(userVoltage5V);
+void RoboRioSim::SetUserVoltage5V(units::volt_t userVoltage5V) {
+  HALSIM_SetRoboRioUserVoltage5V(userVoltage5V.to<double>());
 }
 
 std::unique_ptr<CallbackStore> RoboRioSim::RegisterUserCurrent5VCallback(
@@ -135,12 +139,12 @@ std::unique_ptr<CallbackStore> RoboRioSim::RegisterUserCurrent5VCallback(
   return store;
 }
 
-double RoboRioSim::GetUserCurrent5V() {
-  return HALSIM_GetRoboRioUserCurrent5V();
+units::ampere_t RoboRioSim::GetUserCurrent5V() {
+  return units::ampere_t(HALSIM_GetRoboRioUserCurrent5V());
 }
 
-void RoboRioSim::SetUserCurrent5V(double userCurrent5V) {
-  HALSIM_SetRoboRioUserCurrent5V(userCurrent5V);
+void RoboRioSim::SetUserCurrent5V(units::ampere_t userCurrent5V) {
+  HALSIM_SetRoboRioUserCurrent5V(userCurrent5V.to<double>());
 }
 
 std::unique_ptr<CallbackStore> RoboRioSim::RegisterUserActive5VCallback(
@@ -167,12 +171,12 @@ std::unique_ptr<CallbackStore> RoboRioSim::RegisterUserVoltage3V3Callback(
   return store;
 }
 
-double RoboRioSim::GetUserVoltage3V3() {
-  return HALSIM_GetRoboRioUserVoltage3V3();
+units::volt_t RoboRioSim::GetUserVoltage3V3() {
+  return units::volt_t(HALSIM_GetRoboRioUserVoltage3V3());
 }
 
-void RoboRioSim::SetUserVoltage3V3(double userVoltage3V3) {
-  HALSIM_SetRoboRioUserVoltage3V3(userVoltage3V3);
+void RoboRioSim::SetUserVoltage3V3(units::volt_t userVoltage3V3) {
+  HALSIM_SetRoboRioUserVoltage3V3(userVoltage3V3.to<double>());
 }
 
 std::unique_ptr<CallbackStore> RoboRioSim::RegisterUserCurrent3V3Callback(
@@ -184,12 +188,12 @@ std::unique_ptr<CallbackStore> RoboRioSim::RegisterUserCurrent3V3Callback(
   return store;
 }
 
-double RoboRioSim::GetUserCurrent3V3() {
-  return HALSIM_GetRoboRioUserCurrent3V3();
+units::ampere_t RoboRioSim::GetUserCurrent3V3() {
+  return units::ampere_t(HALSIM_GetRoboRioUserCurrent3V3());
 }
 
-void RoboRioSim::SetUserCurrent3V3(double userCurrent3V3) {
-  HALSIM_SetRoboRioUserCurrent3V3(userCurrent3V3);
+void RoboRioSim::SetUserCurrent3V3(units::ampere_t userCurrent3V3) {
+  HALSIM_SetRoboRioUserCurrent3V3(userCurrent3V3.to<double>());
 }
 
 std::unique_ptr<CallbackStore> RoboRioSim::RegisterUserActive3V3Callback(
diff --git a/wpilibc/src/main/native/include/frc/simulation/RoboRioSim.h b/wpilibc/src/main/native/include/frc/simulation/RoboRioSim.h
index 5da668a941..32eb4625e6 100644
--- a/wpilibc/src/main/native/include/frc/simulation/RoboRioSim.h
+++ b/wpilibc/src/main/native/include/frc/simulation/RoboRioSim.h
@@ -9,6 +9,9 @@
 
 #include <memory>
 
+#include <units/current.h>
+#include <units/voltage.h>
+
 #include "frc/simulation/CallbackStore.h"
 
 namespace frc {
@@ -29,30 +32,30 @@ class RoboRioSim {
   static std::unique_ptr<CallbackStore> RegisterVInVoltageCallback(
       NotifyCallback callback, bool initialNotify);
 
-  static double GetVInVoltage();
+  static units::volt_t GetVInVoltage();
 
-  static void SetVInVoltage(double vInVoltage);
+  static void SetVInVoltage(units::volt_t vInVoltage);
 
   static std::unique_ptr<CallbackStore> RegisterVInCurrentCallback(
       NotifyCallback callback, bool initialNotify);
 
-  static double GetVInCurrent();
+  static units::ampere_t GetVInCurrent();
 
-  static void SetVInCurrent(double vInCurrent);
+  static void SetVInCurrent(units::ampere_t vInCurrent);
 
   static std::unique_ptr<CallbackStore> RegisterUserVoltage6VCallback(
       NotifyCallback callback, bool initialNotify);
 
-  static double GetUserVoltage6V();
+  static units::volt_t GetUserVoltage6V();
 
-  static void SetUserVoltage6V(double userVoltage6V);
+  static void SetUserVoltage6V(units::volt_t userVoltage6V);
 
   static std::unique_ptr<CallbackStore> RegisterUserCurrent6VCallback(
       NotifyCallback callback, bool initialNotify);
 
-  static double GetUserCurrent6V();
+  static units::ampere_t GetUserCurrent6V();
 
-  static void SetUserCurrent6V(double userCurrent6V);
+  static void SetUserCurrent6V(units::ampere_t userCurrent6V);
 
   static std::unique_ptr<CallbackStore> RegisterUserActive6VCallback(
       NotifyCallback callback, bool initialNotify);
@@ -64,16 +67,16 @@ class RoboRioSim {
   static std::unique_ptr<CallbackStore> RegisterUserVoltage5VCallback(
       NotifyCallback callback, bool initialNotify);
 
-  static double GetUserVoltage5V();
+  static units::volt_t GetUserVoltage5V();
 
-  static void SetUserVoltage5V(double userVoltage5V);
+  static void SetUserVoltage5V(units::volt_t userVoltage5V);
 
   static std::unique_ptr<CallbackStore> RegisterUserCurrent5VCallback(
       NotifyCallback callback, bool initialNotify);
 
-  static double GetUserCurrent5V();
+  static units::ampere_t GetUserCurrent5V();
 
-  static void SetUserCurrent5V(double userCurrent5V);
+  static void SetUserCurrent5V(units::ampere_t userCurrent5V);
 
   static std::unique_ptr<CallbackStore> RegisterUserActive5VCallback(
       NotifyCallback callback, bool initialNotify);
@@ -85,16 +88,16 @@ class RoboRioSim {
   static std::unique_ptr<CallbackStore> RegisterUserVoltage3V3Callback(
       NotifyCallback callback, bool initialNotify);
 
-  static double GetUserVoltage3V3();
+  static units::volt_t GetUserVoltage3V3();
 
-  static void SetUserVoltage3V3(double userVoltage3V3);
+  static void SetUserVoltage3V3(units::volt_t userVoltage3V3);
 
   static std::unique_ptr<CallbackStore> RegisterUserCurrent3V3Callback(
       NotifyCallback callback, bool initialNotify);
 
-  static double GetUserCurrent3V3();
+  static units::ampere_t GetUserCurrent3V3();
 
-  static void SetUserCurrent3V3(double userCurrent3V3);
+  static void SetUserCurrent3V3(units::ampere_t userCurrent3V3);
 
   static std::unique_ptr<CallbackStore> RegisterUserActive3V3Callback(
       NotifyCallback callback, bool initialNotify);
diff --git a/wpilibc/src/test/native/cpp/simulation/StateSpaceSimTest.cpp b/wpilibc/src/test/native/cpp/simulation/StateSpaceSimTest.cpp
index 6aa30ca108..5766751580 100644
--- a/wpilibc/src/test/native/cpp/simulation/StateSpaceSimTest.cpp
+++ b/wpilibc/src/test/native/cpp/simulation/StateSpaceSimTest.cpp
@@ -47,7 +47,7 @@ TEST(StateSpaceSimTest, TestFlywheelSim) {
 
     // Then, SimulationPeriodic runs
     frc::sim::RoboRioSim::SetVInVoltage(
-        frc::sim::BatterySim::Calculate({sim.GetCurrentDraw()}).to<double>());
+        frc::sim::BatterySim::Calculate({sim.GetCurrentDraw()}));
     sim.SetInput(frc::MakeMatrix<1, 1>(
         motor.Get() * frc::RobotController::GetInputVoltage()));
     sim.Update(20_ms);
diff --git a/wpilibcExamples/src/main/cpp/examples/ArmSimulation/cpp/Robot.cpp b/wpilibcExamples/src/main/cpp/examples/ArmSimulation/cpp/Robot.cpp
index 116ee1bca9..18df257406 100644
--- a/wpilibcExamples/src/main/cpp/examples/ArmSimulation/cpp/Robot.cpp
+++ b/wpilibcExamples/src/main/cpp/examples/ArmSimulation/cpp/Robot.cpp
@@ -82,8 +82,7 @@ class Robot : public frc::TimedRobot {
     m_encoderSim.SetDistance(m_armSim.GetAngle().to<double>());
     // SimBattery estimates loaded battery voltages
     frc::sim::RoboRioSim::SetVInVoltage(
-        frc::sim::BatterySim::Calculate({m_armSim.GetCurrentDraw()})
-            .to<double>());
+        frc::sim::BatterySim::Calculate({m_armSim.GetCurrentDraw()}));
   }
 
   void TeleopPeriodic() {
diff --git a/wpilibcExamples/src/main/cpp/examples/ElevatorSimulation/cpp/Robot.cpp b/wpilibcExamples/src/main/cpp/examples/ElevatorSimulation/cpp/Robot.cpp
index b342639b0b..1f6744938c 100644
--- a/wpilibcExamples/src/main/cpp/examples/ElevatorSimulation/cpp/Robot.cpp
+++ b/wpilibcExamples/src/main/cpp/examples/ElevatorSimulation/cpp/Robot.cpp
@@ -81,8 +81,7 @@ class Robot : public frc::TimedRobot {
     m_encoderSim.SetDistance(m_elevatorSim.GetPosition().to<double>());
     // SimBattery estimates loaded battery voltages
     frc::sim::RoboRioSim::SetVInVoltage(
-        frc::sim::BatterySim::Calculate({m_elevatorSim.GetCurrentDraw()})
-            .to<double>());
+        frc::sim::BatterySim::Calculate({m_elevatorSim.GetCurrentDraw()}));
   }
 
   void TeleopPeriodic() {