path: root/src/modules/uavcan/esc_controller.cpp

/****************************************************************************
 *
 *   Copyright (C) 2014 PX4 Development Team. All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 *
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in
 *    the documentation and/or other materials provided with the
 *    distribution.
 * 3. Neither the name PX4 nor the names of its contributors may be
 *    used to endorse or promote products derived from this software
 *    without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
 * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
 * COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
 * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS
 * OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
 * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN
 * ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
 * POSSIBILITY OF SUCH DAMAGE.
 *
 ****************************************************************************/

/**
 * @file esc_controller.cpp
 *
 * @author Pavel Kirienko <pavel.kirienko@gmail.com>
 */

#include "esc_controller.hpp"
#include <systemlib/err.h>

UavcanEscController::UavcanEscController(uavcan::INode &node) :
	_node(node),
	_uavcan_pub_raw_cmd(node),
	_uavcan_sub_status(node),
	_orb_timer(node)
{
}

UavcanEscController::~UavcanEscController()
{
	perf_free(_perfcnt_invalid_input);
	perf_free(_perfcnt_scaling_error);
}

int UavcanEscController::init()
{
	// ESC status subscription
	int res = _uavcan_sub_status.start(StatusCbBinder(this, &UavcanEscController::esc_status_sub_cb));
	if (res < 0)
	{
		warnx("ESC status sub failed %i", res);
		return res;
	}

	// ESC status will be relayed from UAVCAN bus into ORB at this rate
	_orb_timer.setCallback(TimerCbBinder(this, &UavcanEscController::orb_pub_timer_cb));
	_orb_timer.startPeriodic(uavcan::MonotonicDuration::fromMSec(1000 / ESC_STATUS_UPDATE_RATE_HZ));

	return res;
}

void UavcanEscController::update_outputs(float *outputs, unsigned num_outputs)
{
	if ((outputs == nullptr) || (num_outputs > MAX_ESCS)) {
		perf_count(_perfcnt_invalid_input);
		return;
	}

	/*
	 * Rate limiting - we don't want to congest the bus
	 */
	const auto timestamp = _node.getMonotonicTime();
	if ((timestamp - _prev_cmd_pub).toUSec() < (1000000 / MAX_RATE_HZ)) {
		return;
	}
	_prev_cmd_pub = timestamp;

	/*
	 * Fill the command message
	 * If unarmed, we publish an empty message anyway
	 */
	uavcan::equipment::esc::RawCommand msg;

	if (_armed) {
		for (unsigned i = 0; i < num_outputs; i++) {

			float scaled = (outputs[i] + 1.0F) * 0.5F * uavcan::equipment::esc::RawCommand::CMD_MAX;
			if (scaled < 1.0F) {
				scaled = 1.0F;  // Since we're armed, we don't want to stop it completely
			}

			if (scaled < uavcan::equipment::esc::RawCommand::CMD_MIN) {
				scaled = uavcan::equipment::esc::RawCommand::CMD_MIN;
				perf_count(_perfcnt_scaling_error);
			} else if (scaled > uavcan::equipment::esc::RawCommand::CMD_MAX) {
				scaled = uavcan::equipment::esc::RawCommand::CMD_MAX;
				perf_count(_perfcnt_scaling_error);
			} else {
				; // Correct value
			}

			msg.cmd.push_back(static_cast<unsigned>(scaled));
		}
	}

	/*
	 * Publish the command message to the bus
	 * Note that for a quadrotor it takes one CAN frame
	 */
	(void)_uavcan_pub_raw_cmd.broadcast(msg);
}

void UavcanEscController::arm_esc(bool arm)
{
	_armed = arm;
}

void UavcanEscController::esc_status_sub_cb(const uavcan::ReceivedDataStructure<uavcan::equipment::esc::Status> &msg)
{
	// TODO save status into a local storage; publish to ORB later from orb_pub_timer_cb()
}

void UavcanEscController::orb_pub_timer_cb(const uavcan::TimerEvent&)
{
	// TODO publish to ORB
}