implement and use tinkerforge_imu2 node in cpp

[ros_wild_thumper.git] / src / tinkerforge_imu2.cpp

diff --git a/src/tinkerforge_imu2.cpp b/src/tinkerforge_imu2.cpp
new file mode 100644 (file)
index 0000000..d07b8e7
--- /dev/null
+++ b/src/tinkerforge_imu2.cpp
@@ -0,0 +1,88 @@
+#include <stdio.h>
+#include <math.h>
+#include "ros/ros.h"
+#include "sensor_msgs/Imu.h"
+#include "ip_connection.h"
+#include "brick_imu_v2.h"
+
+ros::Publisher pub_imu;
+
+void cb_all_data(int16_t acceleration[3], int16_t magnetic_field[3], int16_t angular_velocity[3], int16_t euler_angle[3], int16_t quaternion[4], int16_t linear_acceleration[3], int16_t gravity_vector[3], int8_t temperature, uint8_t calibration_status, void *user_data) {
+       sensor_msgs::Imu msg;
+       msg.header.stamp = ros::Time::now();
+       msg.header.frame_id = "base_imu_link";
+
+       msg.orientation.x = quaternion[1]/16383.0;
+       msg.orientation.y = quaternion[2]/16383.0;
+       msg.orientation.z = quaternion[3]/16383.0;
+       msg.orientation.w = quaternion[0]/16383.0;
+       // Observed orientation variance: 0.0 (10k samples)
+       // Magnometer heading accuracy is +-2.5 deg => 0.088 rad
+       // With heading accuracy as std dev, variance = 0.088^2 = 0.008 
+       msg.orientation_covariance = {
+               0.008, 0     , 0,
+               0    , 0.008, 0,
+               0    , 0    , 0.008
+       };
+
+       msg.angular_velocity.x = angular_velocity[0]/16.0*M_PI/180;
+       msg.angular_velocity.y = angular_velocity[1]/16.0*M_PI/180;
+       msg.angular_velocity.z = angular_velocity[2]/16.0*M_PI/180;
+       // Observed angular velocity variance: 0.006223 (10k samples), => round up to 0.02
+       msg.angular_velocity_covariance = {
+               0.02, 0   , 0,
+               0   , 0.02, 0,
+               0   , 0   , 0.02
+       };
+
+       msg.linear_acceleration.x = acceleration[0]/100.0;
+       msg.linear_acceleration.y = acceleration[1]/100.0;
+       msg.linear_acceleration.z = acceleration[2]/100.0;
+       // Observed linear acceleration variance: 0.001532 (10k samples)
+       // Calculation for variance taken from razor imu:
+       // nonliniarity spec: 1% of full scale (+-2G) => 0.2m/s^2
+       // Choosing 0.2 as std dev, variance = 0.2^2 = 0.04
+       msg.linear_acceleration_covariance = {
+               0.04, 0    , 0,
+               0    , 0.04, 0,
+               0    , 0    , 0.04
+       };
+
+       pub_imu.publish(msg);
+}
+
+int main(int argc, char **argv) {
+       std::string host, uid;
+       int port;
+       IPConnection ipcon;
+       IMUV2 imu;
+
+       ros::init(argc, argv, "imu_brick_v2");
+       ros::NodeHandle nh;
+       ros::NodeHandle pnh("~");
+
+       pub_imu = nh.advertise<sensor_msgs::Imu>("imu", 10);
+
+       pnh.param("host", host, std::string("localhost"));
+       pnh.param("port", port, 4223);
+       pnh.getParam("uid", uid);
+
+       // Create IP connection
+       ipcon_create(&ipcon);
+       // Create device object
+       imu_v2_create(&imu, uid.c_str(), &ipcon);
+       // Connect to brickd
+       if(ipcon_connect(&ipcon, host.c_str(), port) < 0) {
+               fprintf(stderr, "Could not connect\n");
+               return 1;
+       }
+       imu_v2_leds_off(&imu);
+       imu_v2_disable_status_led(&imu);
+       imu_v2_register_callback(&imu, IMU_V2_CALLBACK_ALL_DATA, (void (*)(void))cb_all_data, NULL);
+       imu_v2_set_all_data_period(&imu, 20); // ms
+
+       ros::spin();
+
+       imu_v2_destroy(&imu);
+       ipcon_destroy(&ipcon); // Calls ipcon_disconnect internally
+}