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When you sign up to Artefacts, you will be automatically added to the artefacts-demos organization, containing a number of example projects.
You can access the output of these projects at https://app.artefacts.com/artefacts-demos
Currently available examples:
Demo available here.. Note: Registration required.
OpenRMF is a framework for multi robot interoperability in large buildings. One common configuration task in OpenRMF is to set up Places and navigation lanes for the robots in a building.
Here we run the OpenRMF demo on the office world.
As shown below, this map has 14 waypoints where a robot can go. It also comes with 2 “tinyRobot"s starting on their respective chargers.
The goal of this test demo is to send every robot to every waypoint, and assert that it arrives. Failure indicates that a robot is unable to reach a place on the map.
The test is parametrized to run through all robots and waypoints, resetting the simulation between each run.
“tinyRobot2” successfully reached “patrol_A1” in ~40s. The video offers additional information on the how well the test executed.
However, “tinyRobot1” could not reach “patrol_B” before the timeout of 120 s. Using the video, we notice that there is a trashcan on the way, so the robot gets stuck on it. The distance graph also points towards the robot being stuck somewhere.
The tests record a few metrics:
The tests record multiple data:
Demo available here. Note: registration required.
The Model Predictive Path Integral (MPPI) is a sampling-based predicitive controller to select optimal trajectories, commonly used in robotics community and well supported by the Nav2 stack.
The core feature of Nav2’s MPPI plugin is its set of objective functions (critics), and can be tuned to achieve a desired behavior for robot planner.
In this demo, we investigate a target behavior where the robot (Locobot) should avoid moving backward. This is prefered by robotic practitioners, and also due to the safety concern in indoor environments, where there can be human or pets, and it’s dangerous for standard robots (i.e: with only front-facing sensors) to move backward without any observation/awareness.
This behavior often occurs due to that, when in sharp turn or a replan asking the robot to turn around (large angular distance), Nav2 MPPI’s Path Angle critic is usually activated and contributes to the scoring. However, it tends to cause the robot to move backward to achieve efficient angular alignment with the planned path.
Most intuitive solution is to use the Prefer Forward critic, and tune its weight so that its cost contribution is higher than Path Angle critic, to counter backward behavior. However, some questions remain if you tune this manually (i.e: blindly adjusting weights):
With Artefacts, we support these answers:
The artefacts.yaml sets up the test and parametrizes as follows:
nav2_mppi_tuning:
type: test
runtime:
framework: ros2:humble
simulator: gazebo:harmonic
timeout: 10 # minutes
scenarios:
defaults:
output_dirs: ["output"]
metrics: "output/metrics.json"
params:
controller_server/FollowPath.PreferForwardCritic.cost_weight: [0.0, 5.0, 70.0]
settings:
- name: reach_goal
pytest_file: "src/locobot_gz_nav2_rtabmap/test/test_mppi.py"
Key points:
pytest, and pytest_file points to our test fileoutput_dirs, and upload to the dashboard.controller_server/FollowPath.PreferForwardCritic.cost_weight: parametrizes the weight values (obtained after observing the critic costs debugging plot). The syntax here indicates a ROS param, following this format: [NODE]/[PARAM], and can be found in Nav2 parameters .yaml file.The test will run three times with three weight values: 0.0 (no contribution), 5.0 (medium contribution), 70.0 (high contribution).
Artefacts dashboard’s runs comparison visualizes critics debugging plot (“Critics vs Time”) and result trajectories plot (“odom vs gt positions”). Here odom is the estimated odometry of robot and can be ignored, we pay attention to gt ground truth positions.
For critics debugging plots, you can isolate critics of interest by double-clicking on one critic, then single-click any next critic:
It can be seen that weight 0.0 leads to zero cost contribution, weight 5.0 raises PreferForwardCritic contribution to nearly same as PathAngleCritic, whereas weight 70.0 can sufficiently surpass its contribution.
The trajectory plots (either in HTML or CSV formats) indicate the influence of increasing PreferForwardCritic contribution:
It can be seen that not until the contribution of PreferForwardCritic surpasses PathAngleCritic (weight 70.0), there remains some “moving backward” behavior of robot, whereas weight 70.0 can successfully guarantee the Locobot only moves forward.
The output videos also confirm the results:
The numerical metrics such as min_velocity_x, traverse_time, traverse_dist, PreferForwardCritic.costs_mean can be used to quickly verify the results without visualization:
The PreferForwardCritic (soft constraint) was targeted in this demo for tuning process to avoid robot reversing, but another approach can be simply setting vx_min = 0.0 (hard constraint), which prevents the controller from sampling any negative forward velocity (essentially a hard ban on reversing). Increasing the weight for “soft constraint” makes forward motion much more likely, but if every forward sample is worse (i.e: path blocked, goal behind robot in a tight corridor), MPPI can still choose a reverse trajectory, which is not possible in the “hard constraint” case.
However, if you start off with the simplest approach (setting vx_min = 0.0) as a common practice, or attempt to deal with other situations where the backward behavior is undesirable (i.e: steering problems on reverse motion, or robot simply cannot move backwards, and in narrow corridors), the similar parametrized testing process can be conducted by simply extending the Artefacts .yaml configuration (adding new job).
json formatHTML formatHTML, CSV formatsFor this project, we used the following helpers from the Artefacts Toolkit:
get_artefacts_params: to determine which PreferForwardCritic weight value to useextract_video: created the videos from the recorded rosbagDemo available here. Note: registration required.
The Tron1 robot is a multi-modal biped robot that can be used for Humanoid RL Research. Much of the software is open source, and can be found here.
In this project, we evaluate Tron1 using two reinforcement learning policies under two complementary conditions:
Together, these experiments allow us to study both active locomotion performance and intrinsic stability characteristics of the policies.
We compare two reinforcement learning policies that share the same high-level objective (bipedal locomotion) but differ in training environment and design assumptions:
isaacgym
A policy trained using NVIDIA Isaac Gym, emphasizing fast, large-scale simulation and efficient optimization. These policies typically prioritize robust execution of commanded motions under simplified or tightly controlled dynamics.
isaaclab
A policy trained using Isaac Lab, emphasizing modularity, richer task abstractions, and closer alignment with downstream robotics workflows. This often introduces additional internal structure and constraints in the policy.
Implementation details and training setups are available at:
We first run a movement test where the robot is asked to move forward and rotate relative to its starting pose. This evaluates how well each policy executes a simple but non-trivial locomotion task.
The test itself is straightforward:
Using the artefacts.yaml file, the movement test is configured as follows:
policy_test:
type: test
runtime:
framework: ros2:jazzy
simulator: gazebo:harmonic
scenarios:
defaults:
pytest_file: test/art_test_move.py
output_dirs: ["test_report/latest/", "output"]
settings:
- name: move_face_with_different_policies
params:
rl_type: ["isaacgym", "isaaclab"]
move_face:
- {name: "dyaw_150+fw_5m", forward_m: 5.0, dyaw_deg: 150, hold: false, timeout_s: 35}
Key points from above:
pytest (and so pytest_file points to our test file).output_dirs for uploads to the dashboardrl_type: two parameters: “isaacgym” and “isaaclab”move_face: one parameter set specifying forward distance (5m), rotation angle (150 degrees), and timeout (35 seconds)The test will run twice, once using the isaacgym policy, and again using the isaaclab policy. Both tests will use the move_face parameter to determine how far, and how much rotation the robot should do.
When using the isaacgym policy, we can see (from a birdseye recording) the robot successfuly rotating, and then moving forwards:
The dashboard notes the test as a success:
And a csv we created during the test plotting the ground truth movement is automatically converted to an easy to read chart by the dashboard.
With the isaaclab policy, we see there is still work to be done. The dashboard notes the test as a fail (and shows us the failing assertion), and the birdseye video shows the robot failing to setout its goal.
We have a csv (automatically converted to a chart) of estimated trajectory, (i.e what the robot thinks it has done), which we can see is widely different to the ground truth:
The movement test evaluates task execution under command. To complement this, we perform an idle drift test, where the robot receives no motion command at all.
After initializing the robot in a neutral standing pose, no velocity, pose, or locomotion commands are issued. The policy continues running normally, and any observed motion is therefore uncommanded.
This test isolates passive stability behavior, independent of task execution.
Idle drift is evaluated at two time scales:
Using both durations allows us to distinguish between short-term stability and long-term equilibrium behavior.
policy_drift:
type: test
runtime:
framework: ros2:jazzy
simulator: gazebo:harmonic
scenarios:
defaults:
output_dirs: ["test_report/latest/", "output"]
metrics: "output/metrics.json"
pytest_file: test/art_test_drift.py
settings:
- name: idle_drift_compare_policies
params:
rl_type: ["isaacgym", "isaaclab"]
durations_s: [10, 60]
Key points from above:
pytest(policy, duration) pairmetrics.json and automatically displayed in the Artefacts dashboardFor each duration, the two policies are compared side-by-side using birdseye recordings.
| isaacgym | isaaclab |
|---|---|
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| isaacgym | isaaclab |
|---|---|
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For each idle drift run, the following ground truth metrics are reported:
An example metrics panel from the dashboard is shown below:
These metrics provide a compact quantitative summary that complements the visual observations.
In addition to scalar metrics, the dashboard provides interactive planar trajectory plots derived from ground truth pose data.
| isaacgym | isaaclab |
|---|---|
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isaacgym exhibits a pronounced curved drift trajectory.isaaclab shows a more linear overall drift direction.| isaacgym | isaaclab |
|---|---|
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The zoomed-in view reveals fine-scale structure:
isaacgym,isaaclab.These patterns are difficult to see in videos alone but become clear when inspecting trajectory data directly.
The movement and idle drift experiments are complementary:
By combining both, we obtain a clearer picture of policy behavior under both active and idle conditions, helping distinguish between execution errors and intrinsic stability characteristics.
For both movement and idle drift experiments, Artefacts provides access to:
For this project, we used the following helpers from the Artefacts Toolkit:
get_artefacts_params: used to select the RL policy and test parametersextract_video: used to generate videos from recorded rosbags