feat: update examples and README with streaming support and uint32 force types

- Change CForce3D fx/fy/fz from int16 to uint32 to match hardware
- Add independent C++ example with command and streaming modes
- Rewrite Python example with threaded streaming (read_loop + consumer pattern)
- Add ROS2 C++ publisher/subscriber examples
- Update README with streaming APIs, ROS2 docs, data type definitions, and full FFI table
- Add CHANGELOG

example/ros-cpp/eskin_publisher.cpp

@@ -0,0 +1,130 @@
+#include <chrono>
+#include <condition_variable>
+#include <cstdint>
+#include <cstdio>
+#include <cstring>
+#include <functional>
+#include <memory>
+#include <mutex>
+#include <queue>
+#include <string>
+#include <thread>
+
+#include "rclcpp/rclcpp.hpp"
+#include "std_msgs/msg/u_int32.hpp"
+
+#include "../include/eskin_ffi.h"
+
+using namespace std::chrono_literals;
+
+class EskinPublisher : public rclcpp::Node {
+public:
+  EskinPublisher(const std::string & device_path)
+  : Node("eskin_publisher"), running_(true)
+  {
+    // 打开设备
+    device_ = eskin_open(device_path.c_str(), nullptr);
+    if (!device_) {
+      RCLCPP_FATAL(this->get_logger(), "Failed to open device: %s", device_path.c_str());
+      rclcpp::shutdown();
+      return;
+    }
+    RCLCPP_INFO(this->get_logger(), "Device opened: %s", device_path.c_str());
+
+    // 启动 streaming
+    auto err = eskin_start_stream(device_);
+    if (err != ESkinSuccess) {
+      RCLCPP_FATAL(this->get_logger(), "Failed to start stream, error: %d", (int)err);
+      eskin_close(device_);
+      rclcpp::shutdown();
+      return;
+    }
+    RCLCPP_INFO(this->get_logger(), "Streaming started");
+
+    // 创建 publisher
+    publisher_ = this->create_publisher<std_msgs::msg::UInt32>("comb_force", 10);
+
+    // 启动独立读取线程
+    read_thread_ = std::thread(&EskinPublisher::read_loop, this);
+
+    // 10ms 定时器：从队列取数据并发布
+    timer_ = this->create_wall_timer(10ms, std::bind(&EskinPublisher::publish_callback, this));
+
+    RCLCPP_INFO(this->get_logger(), "EskinPublisher setup success");
+  }
+
+  ~EskinPublisher() {
+    // 停止读取线程
+    running_ = false;
+    cv_.notify_all();
+    if (read_thread_.joinable()) {
+      read_thread_.join();
+    }
+
+    // 停止 streaming 并关闭设备
+    if (device_) {
+      eskin_stop_stream(device_);
+      eskin_close(device_);
+    }
+    RCLCPP_INFO(this->get_logger(), "EskinPublisher destroyed");
+  }
+
+private:
+  // 独立读取线程：持续从设备读取 sample 放入队列
+  void read_loop() {
+    while (running_) {
+      CFingerSample sample;
+      memset(&sample, 0, sizeof(sample));
+      EskinSdkErrorCode err = eskin_read_sample(device_, 50, &sample);
+      if (err == ESkinSuccess) {
+        std::lock_guard<std::mutex> lock(queue_mutex_);
+        sample_queue_.push(sample);
+        // 限制队列大小，防止堆积
+        while (sample_queue_.size() > 100) {
+          sample_queue_.pop();
+        }
+      } else if (err != ESkinTimeout) {
+        RCLCPP_WARN_THROTTLE(this->get_logger(), *this->get_clock(), 1000,
+          "eskin_read_sample error: %d", (int)err);
+      }
+    }
+  }
+
+  // 定时器回调：从队列取数据并发布到 ROS topic
+  void publish_callback() {
+    std::lock_guard<std::mutex> lock(queue_mutex_);
+    while (!sample_queue_.empty()) {
+      const auto & sample = sample_queue_.front();
+      auto msg = std_msgs::msg::UInt32();
+      // 使用 combined_force 中的 fz（法向力）作为发布值
+      msg.data = static_cast<uint32_t>(sample.combined_force.force.fz);
+      publisher_->publish(msg);
+      sample_queue_.pop();
+    }
+  }
+
+  bool running_;
+  EskinDeviceHandle device_;
+  std::thread read_thread_;
+  std::mutex queue_mutex_;
+  std::queue<CFingerSample> sample_queue_;
+  std::condition_variable cv_;
+
+  rclcpp::TimerBase::SharedPtr timer_;
+  rclcpp::Publisher<std_msgs::msg::UInt32>::SharedPtr publisher_;
+};
+
+int main(int argc, char * argv[]) {
+  rclcpp::init(argc, argv);
+
+  // 设备路径可通过命令行参数传入，默认 /dev/ttyUSB0
+  std::string device_path = "/dev/ttyUSB0";
+  if (argc > 1) {
+    device_path = argv[1];
+  }
+
+  auto node = std::make_shared<EskinPublisher>(device_path);
+  rclcpp::spin(node);
+  rclcpp::shutdown();
+  return 0;
+}