Method
Overview of the seat design approach
The suspension seat design has been realized in collaboration
with several partners: a research team, composed of two
specialists in vibration and two specialists in ergonomics; a
seat manufacturer; and several employees from the Société de
Transport de Montréal (STM), composed of subway operators,
and representatives of the engineering, maintenance, operations,
occupational health and safety and supply departments.
These different partners have been part of the prototype
development, insuring that the prototype was adapted to the
problematic of the MR-73 motor car. The development of the
prototype can be resumed roughly in these different steps:
1) Ergonomic and vibration transmissibility evaluation
of several candidates of suspension seats (cushions
and suspensions evaluated independently for vibration
transmissibility).
2) First version of the prototype that includes all the
ergonomic adjustments and a pneumatic suspension.
The prototype was tested, in a driver cab mock-up, by
several operators having different anthropometries.
3) Second version of the prototype, including several
changes on the seat adjustments, and displacement of
the seat to center the subject weight over the suspension,
in order to avoid excessive pitching of the seat.
This version of the suspension seat is extensively tested
in the lab on a vibration simulator. The suspension
hydraulic damper is removed. Preliminary trials in a
subway cab in operation.
4) Third refined version of the suspension seat. This version
of the prototype is extensively tested in a subway
cab during normal operations.
This paper is focusing on steps 3 and 4 of the prototype
development and validation.