/// -*- tab-width: 4; Mode: C++; c-basic-offset: 4; indent-tabs-mode: nil -*- /* This program is free software: you can redistribute it and/or modify it under the terms of the GNU General Public License as published by the Free Software Foundation, either version 3 of the License, or (at your option) any later version. This program is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for more details. You should have received a copy of the GNU General Public License along with this program. If not, see . */ /* simulator connector for ardupilot version of Gazebo */ #include "SIM_Gazebo.h" #include #include extern const AP_HAL::HAL& hal; namespace SITL { Gazebo::Gazebo(const char *home_str, const char *frame_str) : Aircraft(home_str, frame_str), last_timestamp(0), sock(true) { // try to bind to a specific port so that if we restart ArduPilot // Gazebo keeps sending us packets. Not strictly necessary but // useful for debugging sock.bind("127.0.0.1", 9003); sock.reuseaddress(); sock.set_blocking(false); fprintf(stdout, "bind\n"); } /* decode and send servos */ void Gazebo::send_servos(const struct sitl_input &input) { servo_packet pkt; pkt.motor_speed[0] = (input.servos[0]-1000) / 1000.0f; pkt.motor_speed[1] = (input.servos[1]-1000) / 1000.0f; pkt.motor_speed[2] = (input.servos[2]-1000) / 1000.0f; pkt.motor_speed[3] = (input.servos[3]-1000) / 1000.0f; sock.sendto(&pkt, sizeof(pkt), "127.0.0.1", 9002); } /* receive an update from the FDM This is a blocking function */ void Gazebo::recv_fdm(const struct sitl_input &input) { fdm_packet pkt; /* we re-send the servo packet every 0.1 seconds until we get a reply. This allows us to cope with some packet loss to the FDM */ while (sock.recv(&pkt, sizeof(pkt), 100) != sizeof(pkt)) { send_servos(input); } // get imu stuff accel_body = Vector3f(pkt.imu_linear_acceleration_xyz[0], pkt.imu_linear_acceleration_xyz[1], pkt.imu_linear_acceleration_xyz[2]); gyro = Vector3f(pkt.imu_angular_velocity_rpy[0], pkt.imu_angular_velocity_rpy[1], pkt.imu_angular_velocity_rpy[2]); // compute dcm from imu orientation Quaternion quat(pkt.imu_orientation_quat[0], pkt.imu_orientation_quat[1], pkt.imu_orientation_quat[2], pkt.imu_orientation_quat[3]); quat.rotation_matrix(dcm); double speedN = pkt.velocity_xyz[0]; double speedE = pkt.velocity_xyz[1]; double speedD = pkt.velocity_xyz[2]; velocity_ef = Vector3f(speedN, speedE, speedD); position = Vector3f(pkt.position_xyz[0], pkt.position_xyz[1], pkt.position_xyz[2]); // auto-adjust to simulation frame rate double deltat = pkt.timestamp - last_timestamp; time_now_us += deltat * 1.0e6; if (deltat < 0.01 && deltat > 0) { adjust_frame_time(1.0/deltat); } last_timestamp = pkt.timestamp; /* copied below from iris_ros.py */ /* bearing = to_degrees(atan2(position.y, position.x)); distance = math.sqrt(self.position.x**2 + self.position.y**2) (self.latitude, self.longitude) = util.gps_newpos( self.home_latitude, self.home_longitude, bearing, distance) self.altitude = self.home_altitude - self.position.z velocity_body = self.dcm.transposed() * self.velocity self.accelerometer = self.accel_body.copy() */ } /* update the Gazebo simulation by one time step */ void Gazebo::update(const struct sitl_input &input) { send_servos(input); recv_fdm(input); update_position(); } } // namespace SITL