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

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/**
 * @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)
{
}

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)
{
	assert(outputs != nullptr);
	assert(num_outputs <= MAX_ESCS);

	/*
	 * 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

			assert(scaled >= uavcan::equipment::esc::RawCommand::CMD_MIN);
			assert(scaled <= uavcan::equipment::esc::RawCommand::CMD_MAX);

			msg.cmd.push_back(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
}