Overview

Developed Linux system configuration package deployed to Bear Robotics’ Servi series robots. Single codebase supporting multiple hardware variants (Advantech, ASUS boards / Ubuntu Bionic, Jammy).

Role: System Engineer - package/ module development (16 modules)

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Scope

Area	Modules
Network	0400-network, 0410-lte
Device Management	0300-udev-rules
Security	0500-factory, 2006-firewall, 2008-ssh
Display	1000-kiosk, 1010-plymouth
System Base	0200-base, 0125-scripts

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Technical Highlights

PCI Hash-Based Network Interface Mapping

Interface names (eth0, enp2s0, etc.) vary by board/OS combination.

# Generate hardware fingerprint
lspci | grep -E '(Ethernet|Network)' | sort | md5sum | cut -c1-20

• Hash → semantic name (baseboard, lidar, etc) mapping table
• Substitutes actual interface names at install time

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Time-Based Factory Auto-Lockdown

Automatic security transition after 7 days of /home/factory inactivity.

if ((now - last_modified > 604800)); then  # 7 days
    usermod --lock factory
    idp_rm /home/factory/wifi.*
fi

• Zero manual intervention required
• WiFi credentials auto-cleanup

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udev Rules for Sensor Device Abstraction

Consistent device paths regardless of USB enumeration order.

Sensor	USB ID	Symlink
IMU	10c4:ea60	/dev/penny/imu
Motor Hub	2890:0213	/dev/penny/motor

• 9 sensor types supported
• Motor hub triggers init script on attach (RUN+=)

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Template-Based Dynamic Firewall

UFW rules with placeholders, substituted at install time.

# <ETH_BASEBOARD> → enp2s0 (Advantech Jammy)
modify_rule_files "ETH_BASEBOARD" "${ETH_BASEBOARD}" ${rule_files}

Same security policy applied across all hardware variants.

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Idempotent Script Architecture

All modules use idp_commands.sh wrappers:

• idp_install: Install only if content differs
• idp_changed: Trigger service restart on change
• idp_print_result: Report “CHANGE APPLIED” / “No change”

Safe to re-run during OTA updates.

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Stack

Bash systemd udev NetworkManager UFW Bazel