Lidar combiner node migration to nav2z client (#554)

* Lidar Completion Node migration to nav2z client

* precommit changes

* adding copyright

---------

Co-authored-by: brettpac <brettpac@system76-pc.localdomain>

smacc2_client_library/nav2z_client/nav2z_client/CMakeLists.txt

@@ -112,4 +112,8 @@ install(DIRECTORY include/
   DESTINATION include/
 )
 
+install(FILES scripts/lidar_completion.py
+  DESTINATION lib/${PROJECT_NAME}/
+)
+
 ament_package()

smacc2_client_library/nav2z_client/nav2z_client/scripts/lidar_completion.py

@@ -0,0 +1,105 @@
+# Copyright 2024 RobosoftAI Inc.
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#     http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+
+#!/usr/bin/env python3
+import rclpy
+from rclpy.node import Node
+from sensor_msgs.msg import LaserScan
+from rclpy.qos import QoSProfile, ReliabilityPolicy, HistoryPolicy
+import logging
+import copy
+
+
+class LidarProcessor(Node):
+    def __init__(self):
+        super().__init__("lidar_processor")
+
+        qos_prof_1 = QoSProfile(
+            reliability=ReliabilityPolicy.BEST_EFFORT, history=HistoryPolicy.KEEP_LAST, depth=10
+        )
+
+        self.subscription = self.create_subscription(
+            LaserScan, "/scan_input", self.lidar_callback, qos_profile=qos_prof_1
+        )
+
+        qos_prof_2 = QoSProfile(
+            reliability=ReliabilityPolicy.RELIABLE, history=HistoryPolicy.KEEP_LAST, depth=10
+        )
+
+        self.msg_buffer = []
+        self.publisher = self.create_publisher(LaserScan, "/scan_output", qos_profile=qos_prof_2)
+
+        self.logger = self.get_logger()
+        self.logger.set_level(logging.INFO)
+
+    def lidar_callback(self, msg):
+        # self.logger.info("Received message")
+        self.msg_buffer.append(msg)
+        if len(self.msg_buffer) > 5:
+            # self.logger.info("Merging messages")
+            merged_msg = self.merge_lidar_msgs()
+            # self.msg_buffer.pop(0)
+            self.msg_buffer = []
+            self.publisher.publish(merged_msg)
+
+    def merge_lidar_msgs(self):
+        merged_ranges = [0.0] * len(self.msg_buffer[0].ranges) * len(self.msg_buffer)
+        # cont_inf = 0
+        cont_tot = 0
+        for i in range(len(self.msg_buffer)):
+            for j in range(len(self.msg_buffer[i].ranges)):
+                # if self.msg_buffer[i].ranges[j] != float("inf"):
+                merged_ranges[cont_tot] = self.msg_buffer[i].ranges[j]
+                cont_tot += 1
+                # else:
+                #    cont_inf += 1
+
+        # self.logger.info(f"Number of infinite values from total: {cont_inf}/{cont_tot}")
+
+        merged_msg = LaserScan()
+        # merged_msg = copy.deepcopy(self.msg_buffer[-1])
+        merged_msg.header = self.msg_buffer[-1].header
+
+        merged_msg.time_increment = self.msg_buffer[0].time_increment
+
+        merged_msg.angle_increment = self.msg_buffer[0].angle_increment
+        merged_msg.angle_min = self.msg_buffer[0].angle_min
+        merged_msg.angle_max = (
+            self.msg_buffer[0].angle_min + (len(merged_ranges) - 1) * merged_msg.angle_increment
+        )
+
+        # print(f"first angle_min: {self.msg_buffer[0].angle_min}")
+        # print(f"angle_min: {merged_msg.angle_min}")
+        # print(f"angle_max: {merged_msg.angle_max}")
+
+        # merged_msg.angle_min = self.msg_buffer[0].angle_min - self.msg_buffer[0].angle_increment*len(self.msg_buffer)
+        # merged_msg.angle_max = merged_msg.angle_min + (len(merged_ranges)-1)*merged_msg.angle_increment
+
+        merged_msg.range_min = min(msg.range_min for msg in self.msg_buffer)
+        merged_msg.range_max = max(msg.range_max for msg in self.msg_buffer)
+        merged_msg.ranges = merged_ranges
+
+        return merged_msg
+
+
+def main(args=None):
+    rclpy.init(args=args)
+    lidar_processor = LidarProcessor()
+    rclpy.spin(lidar_processor)
+    lidar_processor.destroy_node()
+    rclpy.shutdown()
+
+
+if __name__ == "__main__":
+    main()