diff --git a/jetson/ros2_ws/src/saltybot_thermal/config/thermal_params.yaml b/jetson/ros2_ws/src/saltybot_thermal/config/thermal_params.yaml
new file mode 100644
index 0000000..813ee07
--- /dev/null
+++ b/jetson/ros2_ws/src/saltybot_thermal/config/thermal_params.yaml
@@ -0,0 +1,6 @@
+thermal_node:
+ ros__parameters:
+ publish_rate_hz: 1.0 # Hz — publish rate for /saltybot/thermal
+ warn_temp_c: 75.0 # Log WARN above this temperature (°C)
+ throttle_temp_c: 85.0 # Log ERROR + set throttled=true above this (°C)
+ thermal_root: "/sys/class/thermal" # Sysfs thermal root; override for tests
diff --git a/jetson/ros2_ws/src/saltybot_thermal/launch/thermal.launch.py b/jetson/ros2_ws/src/saltybot_thermal/launch/thermal.launch.py
new file mode 100644
index 0000000..0eee0f7
--- /dev/null
+++ b/jetson/ros2_ws/src/saltybot_thermal/launch/thermal.launch.py
@@ -0,0 +1,42 @@
+"""thermal.launch.py — Launch the Jetson thermal monitor (Issue #205).
+
+Usage:
+ ros2 launch saltybot_thermal thermal.launch.py
+ ros2 launch saltybot_thermal thermal.launch.py warn_temp_c:=70.0
+"""
+
+import os
+from ament_index_python.packages import get_package_share_directory
+from launch import LaunchDescription
+from launch.actions import DeclareLaunchArgument
+from launch.substitutions import LaunchConfiguration
+from launch_ros.actions import Node
+
+
+def generate_launch_description():
+ pkg = get_package_share_directory("saltybot_thermal")
+ cfg = os.path.join(pkg, "config", "thermal_params.yaml")
+
+ return LaunchDescription([
+ DeclareLaunchArgument("publish_rate_hz", default_value="1.0",
+ description="Publish rate (Hz)"),
+ DeclareLaunchArgument("warn_temp_c", default_value="75.0",
+ description="WARN threshold (°C)"),
+ DeclareLaunchArgument("throttle_temp_c", default_value="85.0",
+ description="THROTTLE threshold (°C)"),
+
+ Node(
+ package="saltybot_thermal",
+ executable="thermal_node",
+ name="thermal_node",
+ output="screen",
+ parameters=[
+ cfg,
+ {
+ "publish_rate_hz": LaunchConfiguration("publish_rate_hz"),
+ "warn_temp_c": LaunchConfiguration("warn_temp_c"),
+ "throttle_temp_c": LaunchConfiguration("throttle_temp_c"),
+ },
+ ],
+ ),
+ ])
diff --git a/jetson/ros2_ws/src/saltybot_thermal/package.xml b/jetson/ros2_ws/src/saltybot_thermal/package.xml
new file mode 100644
index 0000000..771ee91
--- /dev/null
+++ b/jetson/ros2_ws/src/saltybot_thermal/package.xml
@@ -0,0 +1,26 @@
+
+
+
+ saltybot_thermal
+ 0.1.0
+
+ Jetson thermal monitor (Issue #205). Reads /sys/class/thermal/thermal_zone*,
+ publishes /saltybot/thermal JSON at 1 Hz, warns at 75 °C, throttles at 85 °C.
+
+ sl-jetson
+ MIT
+
+ rclpy
+ std_msgs
+
+ ament_python
+
+ ament_copyright
+ ament_flake8
+ ament_pep257
+ python3-pytest
+
+
+ ament_python
+
+
diff --git a/jetson/ros2_ws/src/saltybot_thermal/resource/saltybot_thermal b/jetson/ros2_ws/src/saltybot_thermal/resource/saltybot_thermal
new file mode 100644
index 0000000..e69de29
diff --git a/jetson/ros2_ws/src/saltybot_thermal/saltybot_thermal/__init__.py b/jetson/ros2_ws/src/saltybot_thermal/saltybot_thermal/__init__.py
new file mode 100644
index 0000000..e69de29
diff --git a/jetson/ros2_ws/src/saltybot_thermal/saltybot_thermal/thermal_node.py b/jetson/ros2_ws/src/saltybot_thermal/saltybot_thermal/thermal_node.py
new file mode 100644
index 0000000..ffc5a72
--- /dev/null
+++ b/jetson/ros2_ws/src/saltybot_thermal/saltybot_thermal/thermal_node.py
@@ -0,0 +1,139 @@
+"""thermal_node.py — Jetson CPU/GPU thermal monitor.
+Issue #205
+
+Reads every /sys/class/thermal/thermal_zone* sysfs entry, publishes a JSON
+blob on /saltybot/thermal at a configurable rate (default 1 Hz), and logs
+ROS2 WARN / ERROR when zone temperatures exceed configurable thresholds.
+
+Published topic:
+ /saltybot/thermal (std_msgs/String, JSON)
+
+JSON schema:
+ {
+ "ts": ,
+ "zones": [
+ {"zone": "CPU-therm", "index": 0, "temp_c": 42.5},
+ ...
+ ],
+ "max_temp_c": 55.0,
+ "throttled": false,
+ "warn": false
+ }
+
+Parameters:
+ publish_rate_hz (float, 1.0) — publish rate
+ warn_temp_c (float, 75.0) — log WARN above this temperature
+ throttle_temp_c (float, 85.0) — log ERROR and set throttled=true above this
+ thermal_root (str, "/sys/class/thermal") — sysfs thermal root (override for tests)
+"""
+
+from __future__ import annotations
+
+import json
+import os
+import time
+from typing import List, Optional
+
+import rclpy
+from rclpy.node import Node
+from rclpy.qos import QoSProfile
+from std_msgs.msg import String
+
+
+def read_thermal_zones(root: str) -> List[dict]:
+ """Return a list of {zone, index, temp_c} dicts from sysfs."""
+ zones = []
+ try:
+ entries = sorted(os.listdir(root))
+ except OSError:
+ return zones
+ for entry in entries:
+ if not entry.startswith("thermal_zone"):
+ continue
+ try:
+ idx = int(entry[len("thermal_zone"):])
+ except ValueError:
+ continue
+ zone_dir = os.path.join(root, entry)
+ try:
+ with open(os.path.join(zone_dir, "type")) as f:
+ zone_type = f.read().strip()
+ except OSError:
+ zone_type = entry
+ try:
+ with open(os.path.join(zone_dir, "temp")) as f:
+ temp_mc = int(f.read().strip()) # millidegrees Celsius
+ temp_c = round(temp_mc / 1000.0, 1)
+ except (OSError, ValueError):
+ continue
+ zones.append({"zone": zone_type, "index": idx, "temp_c": temp_c})
+ return zones
+
+
+class ThermalNode(Node):
+ """Reads Jetson thermal zones and publishes /saltybot/thermal at 1 Hz."""
+
+ def __init__(self) -> None:
+ super().__init__("thermal_node")
+
+ self.declare_parameter("publish_rate_hz", 1.0)
+ self.declare_parameter("warn_temp_c", 75.0)
+ self.declare_parameter("throttle_temp_c", 85.0)
+ self.declare_parameter("thermal_root", "/sys/class/thermal")
+
+ self._rate = self.get_parameter("publish_rate_hz").value
+ self._warn_t = self.get_parameter("warn_temp_c").value
+ self._throttle_t = self.get_parameter("throttle_temp_c").value
+ self._root = self.get_parameter("thermal_root").value
+
+ qos = QoSProfile(depth=10)
+ self._pub = self.create_publisher(String, "/saltybot/thermal", qos)
+ self._timer = self.create_timer(1.0 / self._rate, self._publish)
+
+ self.get_logger().info(
+ f"ThermalNode ready (rate={self._rate} Hz, "
+ f"warn={self._warn_t}°C, throttle={self._throttle_t}°C, "
+ f"root={self._root})"
+ )
+
+ def _publish(self) -> None:
+ zones = read_thermal_zones(self._root)
+ if not zones:
+ self.get_logger().warn("No thermal zones found — check thermal_root param")
+ return
+
+ max_temp = max(z["temp_c"] for z in zones)
+ throttled = max_temp >= self._throttle_t
+ warn = max_temp >= self._warn_t
+
+ payload = {
+ "ts": time.time(),
+ "zones": zones,
+ "max_temp_c": max_temp,
+ "throttled": throttled,
+ "warn": warn,
+ }
+ msg = String()
+ msg.data = json.dumps(payload)
+ self._pub.publish(msg)
+
+ if throttled:
+ self.get_logger().error(
+ f"THERMAL THROTTLE: {max_temp}°C >= {self._throttle_t}°C"
+ )
+ elif warn:
+ self.get_logger().warn(
+ f"Thermal warning: {max_temp}°C >= {self._warn_t}°C"
+ )
+
+
+def main(args: Optional[list] = None) -> None:
+ rclpy.init(args=args)
+ node = ThermalNode()
+ try:
+ rclpy.spin(node)
+ except KeyboardInterrupt:
+ pass
+ finally:
+ node.destroy_node()
+ rclpy.shutdown()
diff --git a/jetson/ros2_ws/src/saltybot_thermal/setup.cfg b/jetson/ros2_ws/src/saltybot_thermal/setup.cfg
new file mode 100644
index 0000000..569bb4c
--- /dev/null
+++ b/jetson/ros2_ws/src/saltybot_thermal/setup.cfg
@@ -0,0 +1,4 @@
+[develop]
+script_dir=$base/lib/saltybot_thermal
+[egg_info]
+tag_date = 0
diff --git a/jetson/ros2_ws/src/saltybot_thermal/setup.py b/jetson/ros2_ws/src/saltybot_thermal/setup.py
new file mode 100644
index 0000000..dc67bca
--- /dev/null
+++ b/jetson/ros2_ws/src/saltybot_thermal/setup.py
@@ -0,0 +1,27 @@
+from setuptools import setup
+
+package_name = "saltybot_thermal"
+
+setup(
+ name=package_name,
+ version="0.1.0",
+ packages=[package_name],
+ data_files=[
+ ("share/ament_index/resource_index/packages", [f"resource/{package_name}"]),
+ (f"share/{package_name}", ["package.xml"]),
+ (f"share/{package_name}/launch", ["launch/thermal.launch.py"]),
+ (f"share/{package_name}/config", ["config/thermal_params.yaml"]),
+ ],
+ install_requires=["setuptools"],
+ zip_safe=True,
+ maintainer="sl-jetson",
+ maintainer_email="sl-jetson@saltylab.local",
+ description="Jetson thermal monitor — /saltybot/thermal JSON at 1 Hz",
+ license="MIT",
+ tests_require=["pytest"],
+ entry_points={
+ "console_scripts": [
+ "thermal_node = saltybot_thermal.thermal_node:main",
+ ],
+ },
+)
diff --git a/jetson/ros2_ws/src/saltybot_thermal/test/test_thermal.py b/jetson/ros2_ws/src/saltybot_thermal/test/test_thermal.py
new file mode 100644
index 0000000..0c64b64
--- /dev/null
+++ b/jetson/ros2_ws/src/saltybot_thermal/test/test_thermal.py
@@ -0,0 +1,303 @@
+"""test_thermal.py -- Unit tests for Issue #205 Jetson thermal monitor."""
+
+from __future__ import annotations
+import json, os, time
+import pytest
+
+
+def _pkg_root():
+ return os.path.dirname(os.path.dirname(os.path.abspath(__file__)))
+
+
+def _read_src(rel_path):
+ with open(os.path.join(_pkg_root(), rel_path)) as f:
+ return f.read()
+
+
+# ── Import the sysfs reader (no ROS required) ─────────────────────────────────
+
+def _import_reader():
+ import importlib.util, sys, types
+
+ # Build minimal ROS2 stubs so thermal_node.py imports without a ROS install
+ def _stub(name):
+ m = types.ModuleType(name)
+ sys.modules[name] = m
+ return m
+
+ rclpy_mod = _stub("rclpy")
+ rclpy_node_mod = _stub("rclpy.node")
+ rclpy_qos_mod = _stub("rclpy.qos")
+ std_msgs_mod = _stub("std_msgs")
+ std_msg_mod = _stub("std_msgs.msg")
+
+ class _Node:
+ def __init__(self, *a, **kw): pass
+ def declare_parameter(self, *a, **kw): pass
+ def get_parameter(self, name):
+ class _P:
+ value = None
+ return _P()
+ def create_publisher(self, *a, **kw): return None
+ def create_timer(self, *a, **kw): return None
+ def get_logger(self):
+ class _L:
+ def info(self, *a): pass
+ def warn(self, *a): pass
+ def error(self, *a): pass
+ return _L()
+ def destroy_node(self): pass
+
+ class _QoSProfile:
+ def __init__(self, **kw): pass
+
+ class _String:
+ data = ""
+
+ rclpy_node_mod.Node = _Node
+ rclpy_qos_mod.QoSProfile = _QoSProfile
+ std_msg_mod.String = _String
+ rclpy_mod.init = lambda *a, **kw: None
+ rclpy_mod.spin = lambda node: None
+ rclpy_mod.ok = lambda: True
+ rclpy_mod.shutdown = lambda: None
+
+ spec = importlib.util.spec_from_file_location(
+ "thermal_node_testmod",
+ os.path.join(_pkg_root(), "saltybot_thermal", "thermal_node.py"),
+ )
+ mod = importlib.util.module_from_spec(spec)
+ spec.loader.exec_module(mod)
+ return mod
+
+
+# ── Sysfs fixture helpers ─────────────────────────────────────────────────────
+
+def _make_zone(root, idx, zone_type, temp_mc):
+ """Create a fake thermal_zone directory under root."""
+ zdir = os.path.join(str(root), "thermal_zone{}".format(idx))
+ os.makedirs(zdir, exist_ok=True)
+ with open(os.path.join(zdir, "type"), "w") as f:
+ f.write(zone_type + "\n")
+ with open(os.path.join(zdir, "temp"), "w") as f:
+ f.write(str(temp_mc) + "\n")
+
+
+# ── read_thermal_zones ────────────────────────────────────────────────────────
+
+class TestReadThermalZones:
+ @pytest.fixture(scope="class")
+ def mod(self):
+ return _import_reader()
+
+ def test_empty_dir(self, mod, tmp_path):
+ assert mod.read_thermal_zones(str(tmp_path)) == []
+
+ def test_missing_dir(self, mod):
+ assert mod.read_thermal_zones("/nonexistent/path/xyz") == []
+
+ def test_single_zone(self, mod, tmp_path):
+ _make_zone(tmp_path, 0, "CPU-therm", 45000)
+ zones = mod.read_thermal_zones(str(tmp_path))
+ assert len(zones) == 1
+ assert zones[0]["zone"] == "CPU-therm"
+ assert zones[0]["temp_c"] == 45.0
+ assert zones[0]["index"] == 0
+
+ def test_temp_millidegrees_conversion(self, mod, tmp_path):
+ _make_zone(tmp_path, 0, "GPU-therm", 72500)
+ zones = mod.read_thermal_zones(str(tmp_path))
+ assert zones[0]["temp_c"] == 72.5
+
+ def test_multiple_zones(self, mod, tmp_path):
+ _make_zone(tmp_path, 0, "CPU-therm", 40000)
+ _make_zone(tmp_path, 1, "GPU-therm", 55000)
+ _make_zone(tmp_path, 2, "PMIC-Die", 38000)
+ zones = mod.read_thermal_zones(str(tmp_path))
+ assert len(zones) == 3
+
+ def test_sorted_by_index(self, mod, tmp_path):
+ _make_zone(tmp_path, 2, "Z2", 20000)
+ _make_zone(tmp_path, 0, "Z0", 10000)
+ _make_zone(tmp_path, 1, "Z1", 15000)
+ zones = mod.read_thermal_zones(str(tmp_path))
+ indices = [z["index"] for z in zones]
+ assert indices == sorted(indices)
+
+ def test_skips_non_zone_entries(self, mod, tmp_path):
+ os.makedirs(os.path.join(str(tmp_path), "cooling_device0"))
+ _make_zone(tmp_path, 0, "CPU-therm", 40000)
+ zones = mod.read_thermal_zones(str(tmp_path))
+ assert len(zones) == 1
+
+ def test_skips_zone_without_temp(self, mod, tmp_path):
+ zdir = os.path.join(str(tmp_path), "thermal_zone0")
+ os.makedirs(zdir)
+ with open(os.path.join(zdir, "type"), "w") as f:
+ f.write("CPU-therm\n")
+ # No temp file — should be skipped
+ zones = mod.read_thermal_zones(str(tmp_path))
+ assert zones == []
+
+ def test_zone_type_fallback(self, mod, tmp_path):
+ """Zone without type file falls back to directory name."""
+ zdir = os.path.join(str(tmp_path), "thermal_zone0")
+ os.makedirs(zdir)
+ with open(os.path.join(zdir, "temp"), "w") as f:
+ f.write("40000\n")
+ zones = mod.read_thermal_zones(str(tmp_path))
+ assert len(zones) == 1
+ assert zones[0]["zone"] == "thermal_zone0"
+
+ def test_temp_rounding(self, mod, tmp_path):
+ _make_zone(tmp_path, 0, "CPU-therm", 72333)
+ zones = mod.read_thermal_zones(str(tmp_path))
+ assert zones[0]["temp_c"] == 72.3
+
+
+# ── Threshold logic (pure Python) ────────────────────────────────────────────
+
+class TestThresholds:
+ def _classify(self, temp_c, warn_t=75.0, throttle_t=85.0):
+ throttled = temp_c >= throttle_t
+ warn = temp_c >= warn_t
+ return throttled, warn
+
+ def test_normal(self):
+ t, w = self._classify(50.0)
+ assert not t and not w
+
+ def test_warn_boundary(self):
+ t, w = self._classify(75.0)
+ assert not t and w
+
+ def test_below_warn(self):
+ t, w = self._classify(74.9)
+ assert not t and not w
+
+ def test_throttle_boundary(self):
+ t, w = self._classify(85.0)
+ assert t and w
+
+ def test_above_throttle(self):
+ t, w = self._classify(90.0)
+ assert t and w
+
+ def test_custom_thresholds(self):
+ t, w = self._classify(70.0, warn_t=70.0, throttle_t=80.0)
+ assert not t and w
+
+ def test_max_temp_drives_status(self):
+ zones = [{"temp_c": 40.0}, {"temp_c": 86.0}, {"temp_c": 55.0}]
+ max_t = max(z["temp_c"] for z in zones)
+ assert max_t == 86.0
+ t, w = self._classify(max_t)
+ assert t and w
+
+
+# ── JSON payload schema ───────────────────────────────────────────────────────
+
+class TestJsonPayload:
+ def _make_payload(self, zones, warn_t=75.0, throttle_t=85.0):
+ max_temp = max(z["temp_c"] for z in zones) if zones else 0.0
+ return {
+ "ts": time.time(),
+ "zones": zones,
+ "max_temp_c": max_temp,
+ "throttled": max_temp >= throttle_t,
+ "warn": max_temp >= warn_t,
+ }
+
+ def test_has_ts(self):
+ p = self._make_payload([{"zone": "CPU", "index": 0, "temp_c": 40.0}])
+ assert "ts" in p and isinstance(p["ts"], float)
+
+ def test_has_zones(self):
+ p = self._make_payload([{"zone": "CPU", "index": 0, "temp_c": 40.0}])
+ assert "zones" in p and len(p["zones"]) == 1
+
+ def test_has_max_temp(self):
+ p = self._make_payload([{"zone": "CPU", "index": 0, "temp_c": 55.0}])
+ assert p["max_temp_c"] == 55.0
+
+ def test_throttled_false_below(self):
+ p = self._make_payload([{"zone": "CPU", "index": 0, "temp_c": 60.0}])
+ assert p["throttled"] is False
+
+ def test_warn_true_at_threshold(self):
+ p = self._make_payload([{"zone": "CPU", "index": 0, "temp_c": 75.0}])
+ assert p["warn"] is True and p["throttled"] is False
+
+ def test_throttled_true_above(self):
+ p = self._make_payload([{"zone": "CPU", "index": 0, "temp_c": 90.0}])
+ assert p["throttled"] is True
+
+ def test_json_serializable(self):
+ zones = [{"zone": "CPU", "index": 0, "temp_c": 50.0}]
+ p = self._make_payload(zones)
+ blob = json.dumps(p)
+ parsed = json.loads(blob)
+ assert parsed["max_temp_c"] == 50.0
+
+ def test_multi_zone_max(self):
+ zones = [
+ {"zone": "CPU-therm", "index": 0, "temp_c": 55.0},
+ {"zone": "GPU-therm", "index": 1, "temp_c": 78.0},
+ {"zone": "PMIC-Die", "index": 2, "temp_c": 38.0},
+ ]
+ p = self._make_payload(zones)
+ assert p["max_temp_c"] == 78.0
+ assert p["warn"] is True
+ assert p["throttled"] is False
+
+
+# ── Node source checks ────────────────────────────────────────────────────────
+
+class TestNodeSrc:
+ @pytest.fixture(scope="class")
+ def src(self):
+ return _read_src("saltybot_thermal/thermal_node.py")
+
+ def test_class_defined(self, src): assert "class ThermalNode" in src
+ def test_publish_rate_param(self, src): assert '"publish_rate_hz"' in src
+ def test_warn_param(self, src): assert '"warn_temp_c"' in src
+ def test_throttle_param(self, src): assert '"throttle_temp_c"' in src
+ def test_thermal_root_param(self, src): assert '"thermal_root"' in src
+ def test_topic(self, src): assert '"/saltybot/thermal"' in src
+ def test_read_fn(self, src): assert "read_thermal_zones" in src
+ def test_warn_log(self, src): assert "warn" in src.lower()
+ def test_error_log(self, src): assert "error" in src.lower()
+ def test_throttled_flag(self, src): assert '"throttled"' in src
+ def test_warn_flag(self, src): assert '"warn"' in src
+ def test_max_temp(self, src): assert '"max_temp_c"' in src
+ def test_millidegrees(self, src): assert "1000" in src
+ def test_json_dumps(self, src): assert "json.dumps" in src
+ def test_issue_tag(self, src): assert "205" in src
+ def test_main(self, src): assert "def main" in src
+ def test_sysfs_path(self, src): assert "/sys/class/thermal" in src
+
+
+# ── Package metadata ──────────────────────────────────────────────────────────
+
+class TestPackageMeta:
+ @pytest.fixture(scope="class")
+ def pkg_xml(self):
+ return _read_src("package.xml")
+
+ @pytest.fixture(scope="class")
+ def setup_py(self):
+ return _read_src("setup.py")
+
+ @pytest.fixture(scope="class")
+ def cfg(self):
+ return _read_src("config/thermal_params.yaml")
+
+ def test_pkg_name(self, pkg_xml): assert "saltybot_thermal" in pkg_xml
+ def test_issue_tag(self, pkg_xml): assert "205" in pkg_xml
+ def test_entry_point(self, setup_py): assert "thermal_node = saltybot_thermal.thermal_node:main" in setup_py
+ def test_cfg_node_name(self, cfg): assert "thermal_node:" in cfg
+ def test_cfg_warn(self, cfg): assert "warn_temp_c" in cfg
+ def test_cfg_throttle(self, cfg): assert "throttle_temp_c" in cfg
+ def test_cfg_rate(self, cfg): assert "publish_rate_hz" in cfg
+ def test_cfg_defaults(self, cfg):
+ assert "75.0" in cfg and "85.0" in cfg and "1.0" in cfg