TRAILS: Trajectory Generation for Automated Indoor Locomotion Studies
Authors: Juho Kalliokoski, Evan G. Center, Steven M. LaValle, Timo Ojala, Basak Sakcak
Organizations: Faculty of Information Technology and Electrical Engineering, University of Oulu, P.O. Box 4500, Oulu, FI-90014, Finland · Department of Advanced Computing Sciences, Maastricht University, Netherlands
Virtual reality experiments involving navigation and simulated robot motion often require large, realistic environments and numerous distinct trajectories to avoid repetitive navigation while providing sufficient variation for controlled experiments. Designing such scenarios manually is labor-intensive, particularly when trajectories must satisfy predefined geometric and kinematic constraints while remaining diverse and comparable across experimental conditions. This paper presents TRAILS, an automated framework for generating complete virtual navigation scenarios consisting of an environment layout, a path, and a time-parameterized motion profile. The framework combines a constraint-based procedural environment generator inspired by Wave Function Collapse, trajectory generation using optimized cubic Bézier curves, and speed-profile generation subject to kinematic constraints. The generated scenarios provide diverse indoor environments with corridors, open spaces, and obstacles, together with trajectories of identical duration that vary in path geometry, wall proximity, and velocity profiles while minimizing systematic dependencies between these characteristics. The framework is designed as an easy-to-use tool requiring only a small number of intuitive user-defined parameters to automatically generate large sets of distinct navigation scenarios satisfying prescribed geometric and kinematic constraints. By relying on explicit, seed-controlled algorithmic procedures rather than data-driven models, the generated scenarios remain transparent, reproducible, and configurable, making the framework well suited for telepresence and human-subject experiments. The code is available at https://github.com/JucciK/Trails .
Figures & tables
Fig. 1: Overview of the TRAILS framework.
Fig. 2: Tile adjacency constraints. (Left) Each side of a tile is assigned an interface label. A tile can be placed adjacent to another tile only if the labels on the shared edge are compatible. (Middle) Compatible neighboring tiles satisfying adjacency constraints. (Right) Incompatible neighboring tiles.
Fig. 3: Example environment (top-view) generated by the proposed framework together with four generated paths.
Fig. 4: Linear velocity profiles corresponding to the trajectories shown in Fig. 3 . The profiles consist of piecewise constant-velocity segments connected by constant-acceleration transitions while satisfying the prescribed motion constraints.
Parameter
Value
Minimum number of tiles
500
Maximum endpoint offset αmax
0.4
Maximum control-point angle ϕmax
1.0 rad
Control-point distance [dmin,dmax]
[0.25,1.5] m
Minimum wall clearance dwall
0.30 m
Maximum angular velocity ωmax
π rad/s
TABLE I: Parameters used in the numerical example.