yellow

shopping

metal

outdoor

transport

black

technology

traffic

repeat

motion

flow

building

industry

structure

service

indoor

moving

phone

smart

chain

step

floor

track

safety

cycle

move

footage

video

carry

motor

platform

mall

airport

transit

staircase

upward

downward

manage

stair

capacity

operation

endless

convenient

function

driven

escalator

department store