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This paper presents a new composite drive cycle used to evaluate and test the performance of Class 4-6 heavy-duty hybrid electric vehicles (HEVs). The new cycle is being used in the ongoing Advanced Heavy Hybrid Propulsion Systems (AHHPS) Program, sponsored by the U.S. Department of Energy. The goal was to select a cycle that is acceptable to all involved parties, has an achievable speed-time trace for target applications, represents the typical driving pattern of these applications, and is practical for testing and state-of-charge correction. These criteria were applied to numerous element and composite cycles. Ultimately, a new composite cycle was developed and selected-the Combined International Local and Commuter Cycle (CILCC). Various activities conducted under the AHHPS Program are based on this cycle, including energy auditing, modeling and simulation, system optimization, and vehicle testing.

For more than a decade, automotive engineers have refined their techniques for developing control systems in automotive powertrain applications. One critical element of the product development process is real-time calibration of the control variables. Calibration of automotive powertrain control systems depends heavily on non-intrusive memory access for transparent data acquisition and calibration exercises during engine operation on the dynamometer and in-vehicle driveability testing. This paper provides a brief background and description of the challenges that will be encountered on ECU design projects incorporating 32-bit microprocessors. The most promising solutions to this problem are presented and the tradeoffs associated with their implementation are discussed.