Design of a Dual-Mode Quadruped Robot for Explosive and Narcotics Detection in Railway Environments

This paper presented the proposed design and system architecture of an indigenous dual-mode quadruped robot intended for security inspection in railway environments. The platform combines multiple sensing technologies, including SORS, IMS, THz, GPR, and PIMD, with a 6061-T6 aluminium structural enclosure for protecting the internal electronics. The proposed architecture brings sensing, mobility, computing, thermal management, communication, and safety functions together within a single robotic platform. The two-level computing architecture separates high-level perception from low-level motion control. The Jetson Orin Nano is intended to handle computationally intensive perception and sensing tasks, while the STM32 controller manages low-level motion and balance functions. A control frequency of 500 Hz is defined as a design target for the low-level control loop. The thermal-management design incorporates copper heat pipes and Aerogel insulation to support heat management around the computing and battery sections. These measures are intended to improve heat transfer from the electronics and reduce external heat transfer to the battery compartment during operation in hot outdoor railway environments. For communication and safety, the proposed platform uses 4G LTE as the primary communication link, with LoRa available as a backup when cellular connectivity is unavailable. A 1 TB NVMe SSD provides local storage for sensor and system data during periods of limited connectivity, while the hardware emergency interlock is designed to disconnect the motor power supply during an emergency condition. Overall, the proposed system is intended to provide a mobile inspection platform that can assist security personnel by combining multi-modal sensing, quadruped mobility, onboard computing, local data storage, and communication backup within a single architecture.

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