Automated Railway Sleeper Placement System

The manual sleeper placement workflow was decomposed into discrete robotic actions: pick, assess spacing, translate, place, repeat. Spacing tolerances and cumulative error limits were defined upfront to drive architectural decisions. A gantry arm configuration was selected for its unconstrained vertical motion and simplified kinematics. A mobile base was chosen over fixed guidance to preserve deployment flexibility and modular scalability.

The arm was mounted on a reinforced wheeled base engineered for load stability during dynamic movement. An onboard staging platform reduced the dependency on external material handling equipment. Customized spring-loaded gripper jaws provided passive compliance. Stepper motors with microstepping governed the base. Base movement accuracy was left to software-based displacement estimation.

An RTOS architecture partitioned arm control, base motion, displacement computation, and sequencing into isolated tasks. This ensured deterministic timing, eliminated blocking behavior, and simplified fault isolation. State-driven execution governed synchronization between base translation and arm placement, maintaining predictable mechanical coordination under concurrent operations.

Forward and inverse kinematics translated placement coordinates into joint-space commands, using a vertical-horizontal-vertical gantry topology to reduce motion singularities. Base displacement was computed using controlled wheel rotation, ensuring repeatable positioning accuracy across multiple placement cycles.

Wheel radius constants were empirically calibrated to align theoretical displacement with measured travel. Multi-cycle placement tests quantified cumulative drift and repeatability margins. Motion parameters were tuned to balance mechanical stability with throughput efficiency. The result was a repeatable, structured sleeper placement workflow — demonstrating disciplined system architecture rather than sensor-heavy compensation.