Troubleshooting

CAN Bus Issues

ls -l /sys/class/net/can* shows no devices

• Unplug and replug the USB-CAN adapter
• Try a different USB port
• Run dmesg | tail -20 to check for USB errors
• Verify the adapter firmware (some CANable units need flashing)

RTNETLINK answers: Device or resource busy

sh scripts/reset_all_can.sh

If that fails, unplug the USB-CAN adapter, wait 5 seconds, and replug.

CAN interface is UP but no motor response

• Verify CAN bitrate matches: 1000000 (1 Mbit/s)
• Check that the motor is powered (indicator LED on)
• Check cable polarity (CAN-H, CAN-L, GND)
• Verify motor ID matches what the code expects

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YAM Arm Issues

Motor timeout errors (arm enters damping mode)

The default 400 ms timeout is triggering — your control loop is too slow.

Options:

1. Optimize the control loop to send commands faster than 400 ms
2. Disable the timeout for testing (see Hardware Setup)
3. Contact sales@i2rt.com for bulk firmware with timeout disabled

Arm drifts or vibrates in zero-gravity mode

• Add a PD target to stabilize when using no timeout:

  robot = get_yam_robot(channel="can0", zero_gravity_mode=False)

• Check for loose cable connections at each joint
• Verify the URDF/MuJoCo model matches your arm configuration

Gripper doesn't reach full open/close (linear gripper)

The linear gripper needs to start in the closed position. Calibrate:

1. Power off the arm
2. Manually close the gripper fingers completely
3. Power on and initialize normally

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Flow Base Issues

Remote is unresponsive

Toggle the remote power switch off, wait 3 seconds, power back on. The remote enters sleep mode after inactivity.

Odometry is inaccurate

Wheel odometry is inherently imprecise. For precise localization:

• Use reset_odometry() at known positions
• Integrate a visual odometry sensor (RealSense T265, ZED)

Linear rail not homing

1. Check GPIO connections between the Pi and limit switch
2. Run get_linear_rail_state() to inspect switch state
3. Manually verify both limit switches activate when pressed

Base keeps stopping unexpectedly

The 0.25 s velocity timeout is triggering. Ensure FlowBaseClient maintains its heartbeat — verify your control loop sends commands at > 4 Hz.

RTNETLINK answers: Device or resource busy (Flow Base Pi)

ssh i2rt@172.6.2.20
sh ~/i2rt/scripts/reset_all_can.sh

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Installation Issues

uv pip install -e . fails with build errors

sudo apt install build-essential python3-dev linux-headers-$(uname -r)
uv pip install -e .

MuJoCo viewer doesn't open

• Ensure you have a display (or set up virtual framebuffer for headless)
• Try: export DISPLAY=:0 before running
• On SSH sessions: export MUJOCO_GL=egl for off-screen rendering

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Getting Help

Channel	Link
GitHub Issues	github.com/i2rt-robotics/i2rt/issues
Discord	discord.gg/i2rt
Email	support@i2rt.com
Sales	sales@i2rt.com