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In recent years, Continuously Variable Transmissions (CVTs) have made significant inroads into passenger cars because of advantages over traditional Automatic Transmissions (ATs) such as improved efficiency, reduced weight and smoother operation. However, from an acceleration sound quality perspective, drivers generally seem to prefer the AT sound over the CVT sound, especially in sub-compact/compact vehicle segment with small displacement engines and cost-conscious sound packaging. Vehicles equipped with ATs maintain a linear relationship between vehicle speed and engine RPM during wide-open throttle (WOT) acceleration that is dictated by fixed gear ratios. Vehicles with CVTs typically rise rapidly to a high engine RPM (near peak engine torque) and then dwell at a constant engine RPM as the vehicle speed continues to increase by varying CVT pulley ratios.

Door side intrusion (FMVSS 214, Static) is a quasi-static test to determine the sufficiency of door strength and integrity of its mounting in the event of side impact. Explicit nonlinear solutions are often adapted for simulating the side intrusion test performance using the finite element method. The side intrusion performance involves intense rupture at panels as well as their connections such as spot welds, bolts and hems. The load path changes significantly with the material fracture in the panels and at their connections. Conventional finite element models assuming no material separation cannot capture such load path changes and cannot recognize the associated loss in structural integrity. Accordingly, the conventional nonlinear finite element analysis tends to over-predict the intrusion strengths by a large margin and fails to predict the potential separation of the door from the body at the latch and hinge connections.

The ability to accurately predict roof crush strength as well as the timing of structure intrusion is of great importance in the enhancement of the automotive roof design. Roof crush performance is a complex nonlinear phenomenon involving large-scale deformations and strains with many structural parameters influencing the performance. FMVSS216 testing is being used as an industry standard to determine the sufficiency of body structure strength against a stipulated roof crush load. In this paper, sensitivity of roof crush strength and stiffness predictions in a finite element simulation of FMVSS216 testing condition is studied systematically. Various physical parameters and their mathematical representation in finite element simulations are examined for their contribution to body structure strength as well as stiffness against roof crush loads.

This paper is the second in the series of documents designed to record the progress of a series of SAE documents - SAE J2836™, J2847, J2931, & J2953 - within the Plug-In Electric Vehicle (PEV) Communication Task Force. This follows the initial paper number 2010-01-0837, and continues with the test and modeling of the various PLC types for utility programs described in J2836/1™ & J2847/1. This also extends the communication to an off-board charger, described in J2836/2™ & J2847/2 and includes reverse energy flow described in J2836/3™ and J2847/3. The initial versions of J2836/1™ and J2847/1 were published early 2010. J2847/1 has now been re-opened to include updates from comments from the National Institute of Standards Technology (NIST) Smart Grid Interoperability Panel (SGIP), Smart Grid Architectural Committee (SGAC) and Cyber Security Working Group committee (SCWG).