Colony » Colony Scout

/**

 * Copyright (c) 2011 Colony Project

 * 

 * Permission is hereby granted, free of charge, to any person

 * obtaining a copy of this software and associated documentation

 * files (the "Software"), to deal in the Software without

 * restriction, including without limitation the rights to use,

 * copy, modify, merge, publish, distribute, sublicense, and/or sell

 * copies of the Software, and to permit persons to whom the

 * Software is furnished to do so, subject to the following

 * conditions:

 * 

 * The above copyright notice and this permission notice shall be

 * included in all copies or substantial portions of the Software.

 * 

 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,

 * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES

 * OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND

 * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT

 * HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY,

 * WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING

 * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR

 * OTHER DEALINGS IN THE SOFTWARE.

 **/

/**

 * @file cliffsensor.cpp

 * @brief Contains code to control the cliffsensor.

 *

 * Implementation of functions for cliffsensor use.

 *

 * @author Colony Project, CMU Robotics Club

 * @author Priyanka Deo

 **/

#include "ros/ros.h"

#include "cliffsensor.h"

#include <cstdlib>

/**

 * @defgroup cliffsensor Cliffsensor

 * @brief Functions for using the cliffsensors

 *

 * @{

 **/

/* Cliffsensor state variables

 */

static int front_raw; /**< The current raw value data of the front cliffsensor. */

static int left_raw; /**< The current raw value data of the left cliffsensor. */

static int back_raw; /**< The current raw value data of the right cliffsensor. */

static bool is_cliff; /**< Boolean to represent whether or not there is a cliff. */

/**

 * @brief Changes cliff sensor status

 *

 * Changes cliff sensor status based on subscription to topic cliff_status_changed

 *

 * @param msg The message from the cliff_status_changed topic, containing 

 * status of all cliff sensors.

 */

void changed_cliff_status(const cliffsensor::cliff_status_changed::ConstPtr& msg)

{

  return;

}

/**

 * @brief Outputs status of cliffsensors

 *

 * Serves the service query_cliff by responding to service requests with the

 * status of the cliff sensors.

 * @param req The request. The only field is the units requested.

 * @param res The response. The fields will be filled with values.

 */

bool cliff_query(cliffsensor::query_cliff::Request &req,

                  cliffsensor::query_cliff::Response &res)

{

    int threshold = 500; //TODO fix after figuring out what sensors give us

    res.front_raw = front_raw; 

    res.left_raw = left_raw;

    res.right_raw = back_raw;

    res.cliff_status = is_cliff;

    ROS_DEBUG("Cliffsensor status queried");

    return true;

}

/**

 * @brief Cliffsensor driver. This is a ROS node that controls cliffsensor status.

 *

 * This is the main function for the cliffsensors node. It is run when the node

 * starts and initializes the cliffsensors. It then subscribes to the

 * cliff_status_changed topics, and advertises the

 * query_cliff service.

 * 

 * @param argc The number of command line arguments (should be 1)

 * @param argv The array of command line arguments

 **/

int main(int argc, char **argv)

{

    /* Initialize in ROS the cliffsensor driver node */

    ros::init(argc, argv, "cliffsensor_driver");

    /* Advertise that this serves the query_cliff service */

    ros::NodeHandle n;

    ros::ServiceServer service = n.advertiseService("query_cliff",

                                                    cliff_query);

    /* Subscribe to the cliff_status_changed topic */

    ros::Subscriber sub0 = n.subscribe("cliff_status_changed", 

                                        4, changed_cliff_status);

    /* Initialize hardware for cliffsensors */

    // Hardware init functions here

    ROS_INFO("Ready to query cliffsensors.");

    ros::spin();

    return 0;

}

/** @} **/