diff --git a/aos/common/time.h b/aos/common/time.h
index 1d7ccae..c081e09 100644
--- a/aos/common/time.h
+++ b/aos/common/time.h
@@ -60,6 +60,7 @@
     return ans;
   }
   #endif  // SWIG
+
   // CLOCK_MONOTONIC on the fitpc and CLOCK_REALTIME on the cRIO because the
   // cRIO doesn't have any others.
   // CLOCK_REALTIME is the default realtime clock and CLOCK_MONOTONIC doesn't
@@ -113,6 +114,10 @@
   int ToTicks() const {
     return ToNSec() / static_cast<int64_t>(kNSecInSec / sysClkRateGet());
   }
+  // Constructs a Time representing ticks.
+  static Time InTicks(int ticks) {
+    return Time::InSeconds(ticks * sysClkRateGet());
+  }
 #endif
 
   // Returns the time represented in milliseconds.
@@ -159,6 +164,25 @@
     Check();
   }
 
+  // Absolute value.
+  Time abs() const {
+    if (*this > Time(0, 0)) return *this;
+    return Time(-sec_ - 1, kNSecInSec - nsec_);
+  }
+
+  // Enables returning the mock time value for Now instead of checking the
+  // system clock.  This should only be used when testing things depending on
+  // time, or many things may/will break.
+  static void EnableMockTime(const Time now);
+  // Sets now when time is being mocked.
+  static void SetMockTime(const Time now);
+  // Convenience function to just increment the mock time by a certain amount.
+  static void IncrementMockTime(const Time amount) {
+    SetMockTime(Now() + amount);
+  }
+  // Disables mocking time.
+  static void DisableMockTime();
+
  private:
   int32_t sec_, nsec_;
   // LOG(FATAL)s if nsec_ is >= kNSecInSec.