Share Email Print

Proceedings Paper

A reversibly deployable air dam: a bending approach based on embedded shape memory alloy actuators, Part II: technology demonstration
Format Member Price Non-Member Price
PDF $17.00 $21.00

Paper Abstract

Airflow over/under/around a vehicle can affect many important aspects of vehicle performance including vehicle drag (and through this vehicle fuel economy), vehicle lift and downforce (and through these vehicle stability and handling), and cooling/heat exchange for the vehicle powertrain and air conditioning systems. Known devices in current use to control airflow over/under/around the vehicle are all of fixed geometry, location, orientation, and stiffness. Such devices can thus not be relocated, reoriented, reshaped, etc. as driving conditions change and thus airflow over/under/around the vehicle body cannot be adjusted to better suit the changed driving condition. Additionally, under-vehicle airflow control devices, such as air dams, also reduce ground clearance and thus present a constant challenge to designers to provide the needed control of airflow while maintaining sufficient ground clearance to avoid damage. The research project whose second phase is described herein had its genesis in brainstorming on ways in which the field activated shape and stiffness changing attributes of several classes of active materials could be utilized to produce on-demand deploying/stowing of an air dam. During this second phase, bench top working models were developed, constructed, and successfully exercised this demonstrating the feasibility of an SMA actuator based approach to reversibly deploying an air dam through bending of its flexible structure. Beyond feasibility, the bench top working models demonstrated an active materials based approach which would add little weight to the existing stationary system, and could potentially perform well in the harsh under vehicle environment due to a lack of bearings and pivots. This demonstration showed that actuation speed, force, and cyclic stability all could meet the application requirements.

Paper Details

Date Published: 31 March 2009
PDF: 10 pages
Proc. SPIE 7290, Industrial and Commercial Applications of Smart Structures Technologies 2009, 72900C (31 March 2009); doi: 10.1117/12.812280
Show Author Affiliations
Geoffrey P. McKnight, HRL Labs., LLC (United States)
Alan L. Browne, General Motors Corp. (United States)
Nancy L. Johnson, General Motors Corp. (United States)

Published in SPIE Proceedings Vol. 7290:
Industrial and Commercial Applications of Smart Structures Technologies 2009
Benjamin K. Henderson; M. Brett McMickell, Editor(s)

© SPIE. Terms of Use
Back to Top
Sign in to read the full article
Create a free SPIE account to get access to
premium articles and original research
Forgot your username?