From fd1d0a220f026691f9e65ca64a5d19165889aee4 Mon Sep 17 00:00:00 2001
From: Jacob Perron <jacob@openrobotics.org>
Date: Thu, 25 Mar 2021 16:04:41 -0700
Subject: [PATCH] Use steady clock for computing velocity (#59)

Signed-off-by: Jacob Perron <jacob@openrobotics.org>
---
 include/create/create.h | 2 +-
 src/create.cpp          | 4 ++--
 2 files changed, 3 insertions(+), 3 deletions(-)

diff --git a/include/create/create.h b/include/create/create.h
index 6ca2fe9..deaa4ba 100644
--- a/include/create/create.h
+++ b/include/create/create.h
@@ -80,7 +80,7 @@ namespace create {
       float totalLeftDist;
       float totalRightDist;
       bool firstOnData;
-      std::chrono::time_point<std::chrono::system_clock> prevOnDataTime;
+      std::chrono::time_point<std::chrono::steady_clock> prevOnDataTime;
 
       Matrix poseCovar;
 
diff --git a/src/create.cpp b/src/create.cpp
index 75bfe9a..e8e359e 100644
--- a/src/create.cpp
+++ b/src/create.cpp
@@ -93,12 +93,12 @@ namespace create {
         prevTicksLeft = GET_DATA(ID_LEFT_ENC);
         prevTicksRight = GET_DATA(ID_RIGHT_ENC);
       }
-      prevOnDataTime = std::chrono::system_clock::now();
+      prevOnDataTime = std::chrono::steady_clock::now();
       firstOnData = false;
     }
 
     // Get current time
-    auto curTime = std::chrono::system_clock::now();
+    auto curTime = std::chrono::steady_clock::now();
     float dt = static_cast<std::chrono::duration<float>>(curTime - prevOnDataTime).count();
     float deltaDist, deltaX, deltaY, deltaYaw, leftWheelDist, rightWheelDist, wheelDistDiff;