Added Vacuum class and test

Change-Id: I4c25946b71a0054791a2fc1305eb8ef509a147b1
diff --git a/y2019/control_loops/superstructure/superstructure.cc b/y2019/control_loops/superstructure/superstructure.cc
index 187379b..3443d63 100644
--- a/y2019/control_loops/superstructure/superstructure.cc
+++ b/y2019/control_loops/superstructure/superstructure.cc
@@ -8,35 +8,6 @@
 namespace control_loops {
 namespace superstructure {
 
-void Superstructure::HandleSuction(const SuctionGoal *unsafe_goal,
-                                   float suction_pressure,
-                                   SuperstructureQueue::Output *output,
-                                   bool *has_piece) {
-  constexpr double kPumpVoltage = 12.0;
-  constexpr double kPumpHasPieceVoltage = 8.0;
-
-  // TODO(austin): Low pass filter on pressure.
-  *has_piece = suction_pressure < 0.70;
-
-  if (unsafe_goal && output) {
-    const bool evacuate = unsafe_goal->top || unsafe_goal->bottom;
-    if (evacuate) {
-      vacuum_count_ = 200;
-    }
-    // TODO(austin): High speed pump a bit longer after we detect we have the
-    // game piece.
-    // Once the vacuum evacuates, the pump speeds up because there is no
-    // resistance.  So, we want to turn it down to save the pump from
-    // overheating.
-    output->pump_voltage =
-        (vacuum_count_ > 0) ? (*has_piece ? kPumpHasPieceVoltage : kPumpVoltage)
-                            : 0.0;
-    output->intake_suction_top = unsafe_goal->top;
-    output->intake_suction_bottom = unsafe_goal->bottom;
-  }
-  vacuum_count_ = ::std::max(0, vacuum_count_ - 1);
-}
-
 Superstructure::Superstructure(::aos::EventLoop *event_loop,
                                const ::std::string &name)
     : aos::controls::ControlLoop<SuperstructureQueue>(event_loop, name),
@@ -77,8 +48,9 @@
                   output != nullptr ? &(output->stilts_voltage) : nullptr,
                   &(status->stilts));
 
-  HandleSuction(unsafe_goal != nullptr ? &(unsafe_goal->suction) : nullptr,
-                position->suction_pressure, output, &(status->has_piece));
+  vacuum_.Iterate(unsafe_goal != nullptr ? &(unsafe_goal->suction) : nullptr,
+                  position->suction_pressure, output, &(status->has_piece),
+                  event_loop());
 
   status->zeroed = status->elevator.zeroed && status->wrist.zeroed &&
                    status->intake.zeroed && status->stilts.zeroed;