Mobile ALOHA

Reproduce the selected device arrangement

The README describes persistent USB device names for all four arms and three cameras, plus the Tracer's CAN-to-USB connection. The active launch file starts the high camera and two wrist cameras; a fourth low-camera block is commented out. The overview's reference to four cameras should therefore not be read as the active launch configuration. [S001] [S005]

The guide discourages USB hubs for the arms and limits camera sharing per hub to manage latency. It also notes that Dynamixel Wizard and other camera applications must release devices before the ROS processes connect. Those are configuration requirements from upstream, not proof that an arbitrary computer and USB arrangement will sustain recording. [S001]

The physical assembly tutorial is linked outside the repository. This review did not establish a complete matching set of fabrication files, electronics sources or a current delivered bill of materials. The code's MIT license does not make the purchased arms and mobile base open hardware. [S001] [S003] [S004]

Use a defined ROS and Python environment

The preserved guide reports Ubuntu 20.04 with ROS 1 Noetic as a working configuration; this profile selects that route. ROS 2 and newer Ubuntu versions remain compatibility work in that README. The installation also instructs a local edit to Interbotix code to avoid repeated forward-kinematics computation during position publication. Preserve that edit and the actual dependency revision when recreating the setup. [S001]

The Python environment starts from Python 3.8.10 but installs several packages without pinned versions. This archive is therefore not a complete reproducible environment. No dependencies were installed and no hardware commands were executed for this review. [S001] [S002]

Recorded base action is derived from observations

The episode recorder stores arm observations, images, arm actions and a two-value base_action field. In this revision, base_action is populated from the environment's base_vel observation. That observation reads a separate Dynamixel client at /dev/ttyDXL_wheels, with IDs 1 and 2 and fixed wheel geometry, then derives linear and angular velocity. It is not simply copied from a commanded Tracer velocity. [S006] [S007]

This creates an additional reproduction requirement beyond bringing up the Tracer CAN interface: the selected wheel-feedback device, mapping and geometry must agree with the recording code. The environment contains a separate Tracer velocity getter, but the default base observation follows the Dynamixel path. No claim is made that this feedback configuration was assembled or verified here. [S007]

The recording loop targets 50 FPS. Recollection is triggered when a processing-frequency diagnostic falls below 30 Hz; that diagnostic excludes loop sleep and does not measure the complete recording cadence. Its image path compresses images before saving. These implementation details matter when interpreting saved episodes; merely finding an HDF5 file does not establish correctly synchronized or sufficiently fast data capture. [S006] [S008]

Teleoperation is not a trained policy result

The README recording example uses --dataset_dir, but the reviewed recorder requires --task_name and reads its output directory, episode length and camera names from TASK_CONFIGS in aloha_scripts/constants.py. Select and reconcile that configuration before invoking record_episodes.py with --task_name. This is a code-derived correction to an inconsistent example, not a verified working procedure. [S001] [S006] [S008]

The README's basic one-side teleoperation example does not collect data; episode recording and replay are separate programs. Upstream also instructs users to start from the sleep pose and notes that the arms lack automatically engaged joint brakes when torque is removed. Follow the selected hardware's setup and shutdown procedure before attempting those programs. [S001]

This profile covers the available integration code, not a pretrained policy, released dataset or verified learning result. No installation, device setup, arm motion, mobile driving, recording or replay was performed. [S001] [S003] [S004]