feat: Implement an examplary 6 axis robot

which provides its current measure positions as array in ns=1;100111.

Cargo.toml

@@ -44,3 +44,7 @@ path = "examples/ros2/simple-publisher.rs"
 [[example]]
 name = "simple-subscriber"
 path = "examples/ros2/simple-subscriber.rs"
+
+[[example]]
+name = "sine-joint-positions"
+path = "examples/opc_ua/sine-joint-positions.rs"

examples/opc_ua/sine-joint-positions.rs

@@ -0,0 +1,78 @@
+use opcua::server::prelude::{Config, DateTime, NodeId, Server, ServerConfig, Variable};
+use std::f64::consts::PI;
+use std::path::PathBuf;
+use std::time::SystemTime;
+use std::time::UNIX_EPOCH;
+
+fn main() {
+    sine_joint_positions();
+}
+
+fn sine_joint_positions() {
+    opcua::console_logging::init();
+
+    let mut server =
+        Server::new(ServerConfig::load(&PathBuf::from("tests/resources/clock.conf")).unwrap());
+
+    add_timed_variable_array(&mut server);
+
+    server.run();
+}
+
+fn add_timed_variable_array(server: &mut Server) {
+    // These will be the node id of the variable AxesMeasuredPosition
+    let axes_measured_position = NodeId::new(1, "100111");
+
+    let address_space = server.address_space();
+
+    // The address space is guarded so obtain a lock to change it
+    {
+        let mut address_space = address_space.write();
+
+        let axes_folder_id = address_space
+            .add_folder("Axes", "Axes", &NodeId::objects_folder_id())
+            .unwrap();
+
+        let _ = address_space.add_variables(
+            vec![Variable::new(
+                &axes_measured_position,
+                "AxesMeasuredPosition",
+                "AxesMeasuredPosition",
+                vec![0.0f64; 6],
+            )],
+            &axes_folder_id,
+        );
+    }
+
+    {
+        let omegas: [f64; 6] = [
+            2.0 * PI * 0.25,
+            2.0 * PI * 0.5,
+            2.0 * PI,
+            2.0 * PI * 1.5,
+            2.0 * PI * 2.0,
+            2.0 * PI * 2.5,
+        ];
+
+        server.add_polling_action(10, move || {
+            let mut address_space = address_space.write();
+
+            let timestamp_epoch = SystemTime::now().duration_since(UNIX_EPOCH).unwrap();
+            let seconds =
+                timestamp_epoch.as_secs() as f64 + timestamp_epoch.subsec_nanos() as f64 * 1e-9;
+
+            let sine_values: Vec<f64> = omegas
+                .iter()
+                .map(|&omega| (omega * seconds).sin())
+                .collect();
+
+            let now = DateTime::now();
+            let _ = address_space.set_variable_value(
+                axes_measured_position.clone(),
+                sine_values,
+                &now,
+                &now,
+            );
+        });
+    }
+}