Set Datum

Set the datum. The datum is the reference coordinate of the navigations "map" frame. The XY position of the robot is relative to this location.

• Service Name: localization/set_datum

• Service Type: clearpath_localization_msgs/srv/SetDatum

Python

import rclpy
from rclpy.node import Node

from clearpath_localization_msgs.srv import SetDatum

DATUM_LAT = 43.500049591064453
DATUM_LON = -80.546844482421875

class SetDatum(Node):

    def __init__(self):
        super().__init__('set_datum_client')
        self._srv_client = self.create_client(SetDatum, 'localization/set_datum')
        while not self._srv_client.wait_for_service(timeout_sec=1.0):
            self.get_logger().info('service not available, waiting again...')
        self.req = SetDatum.Request()

    def send_request(self, lat, lon):
        self.req.lat = lat
        self.req.lon = lon
        self.future = self._srv_client.call_async(self.req)
        rclpy.spin_until_future_complete(self, self.future)
        return self.future.result()

if __name__ == '__main__':
    rclpy.init(args=args)
    set_datum_client = SetDatum()
    response = set_datum_client.send_request(DATUM_LAT, DATUM_LON)
    if response.success:
      set_datum_client.get_logger().info('Datum set succesfully: (%s, %s)' % (DATUM_LAT, DATUM_LON))
    else:
      set_datum_client.get_logger().error('Set datum failed!')
    
    set_datum_client.destroy_node()
    rclpy.shutdown()

C++

#include "rclcpp/rclcpp.hpp"
#include "clearpath_localization_msgs/srv/set_datum.hpp"

#include <chrono>
#include <cstdlib>
#include <memory>

using namespace std::chrono_literals;

const double DATUM_LAT = 43.500049591064453;
const double DATUM_LON = -80.546844482421875;

int main(int argc, char **argv)
{
  rclcpp::init(argc, argv);

  std::shared_ptr<rclcpp::Node> node = rclcpp::Node::make_shared("set_datum_client");
  rclcpp::Client<clearpath_localization_msgs::srv::SetDatum>::SharedPtr client =
    node->create_client<clearpath_localization_msgs::srv::SetDatum>("localization/set_datum");

  auto request = std::make_shared<clearpath_localization_msgs::srv::SetDatum::Request>();
  request->lat = DATUM_LAT;
  request->lon = DATUM_LON;

  while (!client->wait_for_service(1s)) {
    if (!rclcpp::ok()) {
      RCLCPP_ERROR(rclcpp::get_logger("rclcpp"), "Interrupted while waiting for the service. Exiting.");
      return 0;
    }
    RCLCPP_INFO(rclcpp::get_logger("rclcpp"), "service not available, waiting again...");
  }

  auto result = client->async_send_request(request);
  // Wait for the result.
  if (rclcpp::spin_until_future_complete(node, result) ==
    rclcpp::FutureReturnCode::SUCCESS)
  {
    if (result.get()->success)
    {
      RCLCPP_INFO(rclcpp::get_logger("rclcpp"), "Datum set successfully: (%s, %s)", );
    }
    else
    {
      RCLCPP_INFO(rclcpp::get_logger("rclcpp"), "Set datum failed!");
    }
  } else {
    RCLCPP_ERROR(rclcpp::get_logger("rclcpp"), "Failed to call service localization/set_datum");
  }

  rclcpp::shutdown();
  return 0;
}