同时还突出显示了伴随call()调用出现死锁的可能情景。 由于我们建议避免同步调用,因此本指南还将介绍推荐的替代方法——异步调用(call_async()) 的特性和用法。 C++服务调用API仅在异步中可用,因此本指南中的比较和示例适用于Python服务端和客户端。这里给出的异步(async)定义通常适用于C++,但也有一些例外。 1. 同...
self.future = self.client.call_async(self.request) def main(): rclpy.init() client_demo = Service_Client("client_node") client_demo.send_request() # 发送服务请求 while rclpy.ok(): rclpy.spin_once(client_demo) # 判断数据是否处理完成 if client_demo.future.done(): try: # 获取服务返回...
self.sub = self.create_subscription(\ ObjectPosition, "/object_position", self.listener_callback, 10) # 创建订阅者对象(消息类型、话题名、订阅者回调函数、队列长度 def listener_callback(self, msg): # 创建回调函数,执行收到话题消息后对数据的处理 self.get_logger().info('Target Position: "(%d...
minimal_client = MinimalClientAsync() minimal_client.send_request() while rclpy.ok(): rclpy.spin_once(minimal_client) if minimal_client.future.done(): try: response = minimal_client.future.result() except Exception as e: minimal_client.get_logger().info( 'Service call failed %r' % (e,)...
self.future=self.client.call_async(self.request)defmain(args=None):rclpy.init(args=args)client=MinimalClient()client.send_request(5,3)# 发送请求:5 + 3rclpy.spin_until_future_complete(client,client.future)ifclient.future.result()isnotNone:client.get_logger().info(f'Result:{client.future.res...
ROS1中常用的client.call(srv)方式不再被ROS2支持,转而使用client->async_send_request(rquest)的异步方式。这种方式会返回一个std::future类型的变量用于检测是否已经获得回应。 在实际移植过程中发现,一个常见的使用场景:client在原地阻塞式的等待request结果将会造成死锁。原...
self._send_goal_future = self._action_client.send_goal_async(goal_msg, feedback_callback=self.feedback_callback) self._send_goal_future.add_done_callback(self.goal_response_callback) def goal_response_callback(self, future): # 处理目标发送后的反馈 goal_handle = future.result() if not...
(self): self.request.get = True self.future= self.client.call_async(self.request)def main(args=None): rclpy.init(args=args) # ROS2 Python接口初始化 node = objectClient("service_object_client") # 创建ROS2节点对象并进行初始化 node.send_re...
Call`ros2 node -h`formore detailed usage. ros2命令支持tab键自动完成。键入ros2,然后按tab键两次以查看可能的关键词。关键词的参数也可以用tab键发现。 比如cpp可执行示例: ros2 pkg executables demo_nodes_cpp 代码语言:javascript 代码运行次数:0 复制 Cloud...
AnyServiceCallback class AnySubscriptionCallback class AsyncParametersClient class CallbackGroup class Client class ClientBase class Clock class Context Context which encapsulates shared state between nodes and other similar entities. More... class ContextAlreadyInitialized Thrown when init is called on an...