y2017/control_loops/superstructure/shooter/shooter.cc

#include "y2017/control_loops/superstructure/shooter/shooter.h"

#include <chrono>

#include "aos/common/controls/control_loops.q.h"
#include "aos/common/logging/logging.h"
#include "aos/common/logging/queue_logging.h"

#include "y2017/control_loops/superstructure/shooter/shooter.h"

namespace y2017 {
namespace control_loops {
namespace superstructure {
namespace shooter {

namespace chrono = ::std::chrono;
using ::aos::monotonic_clock;

namespace {
constexpr double kTolerance = 10.0;
}  // namespace

// TODO(austin): Pseudo current limit?

ShooterController::ShooterController()
    : loop_(new StateFeedbackLoop<4, 1, 1, StateFeedbackHybridPlant<4, 1, 1>,
                                  HybridKalman<4, 1, 1>>(
          superstructure::shooter::MakeIntegralShooterLoop())) {
  history_.fill(0);
  Y_.setZero();
}

void ShooterController::set_goal(double angular_velocity_goal) {
  loop_->mutable_next_R() << 0.0, angular_velocity_goal, angular_velocity_goal,
      0.0;
}

void ShooterController::set_position(double current_position) {
  // Update position in the model.
  Y_ << current_position;

  // Add the position to the history.
  history_[history_position_] = current_position;
  history_position_ = (history_position_ + 1) % kHistoryLength;

  dt_position_ = current_position - last_position_;
  last_position_ = current_position;
}

double ShooterController::voltage() const { return loop_->U(0, 0); }

void ShooterController::Reset() { reset_ = true; }

void ShooterController::Update(bool disabled, chrono::nanoseconds dt) {
  loop_->mutable_R() = loop_->next_R();
  if (::std::abs(loop_->R(2, 0)) < 1.0) {
    // Kill power at low angular velocities.
    disabled = true;
  }

  loop_->Correct(Y_);

  // Compute the oldest point in the history.
  const int oldest_history_position =
      ((history_position_ == 0) ? kHistoryLength : history_position_) - 1;

  // Compute the distance moved over that time period.
  average_angular_velocity_ =
      (history_[oldest_history_position] - history_[history_position_]) /
      (chrono::duration_cast<chrono::duration<double>>(
           ::aos::controls::kLoopFrequency)
           .count() *
       static_cast<double>(kHistoryLength - 1));

  // Ready if average angular velocity is close to the goal.
  error_ = average_angular_velocity_ - loop_->next_R(2, 0);

  ready_ = std::abs(error_) < kTolerance && loop_->next_R(2, 0) > 1.0;

  // If we are no longer ready, but were, and are spinning, then we shot a ball.
  // Reset the KF.
  if (last_ready_ && !ready_ && loop_->next_R(2, 0) > 1.0 && error_ < 0.0) {
    needs_reset_ = true;
    min_velocity_ = velocity();
  }
  if (needs_reset_) {
    min_velocity_ = ::std::min(min_velocity_, velocity());
    if (velocity() > min_velocity_ + 5.0) {
      reset_ = true;
      needs_reset_ = false;
    }
  }
  if (reset_) {
    // TODO(austin): I'd rather not be incrementing X_hat each time.  Sort out
    // something better.
    loop_->mutable_X_hat(3, 0) += 1.0;
    reset_ = false;
  }
  last_ready_ = ready_;

  X_hat_current_ = loop_->X_hat();
  position_error_ = X_hat_current_(0, 0) - Y_(0, 0);
  dt_velocity_ = dt_position_ /
                 chrono::duration_cast<chrono::duration<double>>(dt).count();
  fixed_dt_velocity_ = dt_position_ / 0.00505;

  loop_->Update(disabled, dt);
}

void ShooterController::SetStatus(ShooterStatus *status) {
  status->avg_angular_velocity = average_angular_velocity_;

  status->filtered_velocity = X_hat_current_(1, 0);
  status->angular_velocity = X_hat_current_(2, 0);
  status->ready = ready_;

  status->voltage_error = X_hat_current_(3, 0);
  status->position_error = position_error_;
  status->instantaneous_velocity = dt_velocity_;
  status->fixed_instantaneous_velocity = fixed_dt_velocity_;
}

void Shooter::Reset() { wheel_.Reset(); }

void Shooter::Iterate(const control_loops::ShooterGoal *goal,
                      const double *position,
                      ::aos::monotonic_clock::time_point position_time,
                      double *output, control_loops::ShooterStatus *status) {
  if (goal) {
    // Update position/goal for our wheel.
    wheel_.set_goal(goal->angular_velocity);
  }

  wheel_.set_position(*position);

  chrono::nanoseconds dt = ::aos::controls::kLoopFrequency;
  if (last_time_ != ::aos::monotonic_clock::min_time) {
    dt = position_time - last_time_;
  }
  last_time_ = position_time;

  wheel_.Update(output == nullptr, dt);

  wheel_.SetStatus(status);

  if (last_ready_ && !status->ready) {
    min_ = wheel_.dt_velocity();
  } else if (!status->ready) {
    min_ = ::std::min(min_, wheel_.dt_velocity());
  } else if (!last_ready_ && status->ready) {
    LOG(INFO, "Shot min was [%f]\n", min_);
  }

  if (output) {
    *output = wheel_.voltage();
  }
  last_ready_ = status->ready;
}

}  // namespace shooter
}  // namespace superstructure
}  // namespace control_loops
}  // namespace y2017