Simulation code and results

Human-carried indirect sensing

Jovdat Babazade and Furkan Lüleci · Louisiana State University

A person carries a smartwatch and a smartphone across a flexible deck. The model solves the person and the deck together and records what the devices measure.

Paper	Babazade and Lüleci, under review
Deck	OpenSeesPy, simply supported
Person	15 DOF, walking or standing
Devices	triaxial, wrist and hip
Authors	J. Babazade and F. Lüleci, LSU

One crossing of the deck A person walks across the deck. Below, the vertical acceleration of the left wrist and left hip devices.

1Parameter explorer

Ten parameters, every pair already simulated. Sweep one and compare the deck with the two devices. Click a deck peak to see its mode shape and whether each device found it. Gait lines and the observability index of every mode are shown with it.

ExplorerWalking person20 crossings per configuration. 1207 stored. ExplorerStanding person20 records of 60 s at mid-span. 1015 stored.

2Animations

The baseline deck. Deck motion is exaggerated, the person is to scale.

AnimationWalking, side viewOne crossing at 1.5 m/s. AnimationWalking, 3DThe same crossing in 3D. AnimationStanding, side viewStanding at mid-span. AnimationStanding, 3DThe same record in 3D.

3The model

Deck: Any flexible deck a person walks on: a floor slab, a footbridge, a walkway. Baseline is a 14 m concrete slab, 3 m wide, 0.2 m thick.
Person: Five masses in three directions. Walking force, step timing and arm swing are included.
Coupling: Person and deck are solved together in every time step.
Devices: A watch on each wrist and a phone on each hip, with sensor noise.
Excitation: Three ambient shakers on the deck, plus the person.

4Code

Source, data and run instructions: github.com/covdetbaba/human-carried-indirect-sensing