Sweep Procedures

CAMEO offers Sweep Procedures for gasoline and diesel engines to determine the variation boarderlines and to record the engine torque behavior for the specified ranges.

CAMEO Spark Sweep Procedure

The spark sweep starts from a user-definable point and begins with the MBT search by adjusting the spark timing. After determining the MBT point, the algorithm searches for the knock limit by adjusting the timing towards "early" until either the user-defined variation range limit has been reached or knock was detected (via indicating equipment). The limit is then re-approached with finer resolution and a measurement is taken as close as possible to the limit. The sweep itself is now initiated and the spark timing is adjusted towards "late" until either the user-defined variation range limit or the exhaust temperature limit is reached. The exhaust temperature is modelled using the data coming from the sweep to allow the sweep algorithm to predict where the exhaust gas temperature limit will occur.

Furthermore, the spark sweep algorithm can be used in conjunction with other variation strategies such as full factorial for injection timing & lambda with a spark sweep for every combination.

CAMEO SOI-Sweep Procedure

The SOI-Sweep starts at the location specified by the user and changes the injection timing towards "early" until either the pre-programmed timing limit is reached ot the pre-defined peak cylinder pressure limit is reached. As soon as the peak cylinder pressure limit is activated or NOx limits are reached, the SOI sweep algorithm steps back from the borderline and attemtps to reapproach it using smaller steps in injection timing to locate the borderline as exact as possible. The SOI sweep is then commenced and the timing is adjusted towards "late" until either the exhaust gas temperature limit is reached of predefined HC limits are exceeded. The data is modelled using CAMEO.

The testing time for ECU application/calibration is drastically reduced by combining SOI sweeps described above with full-factorial or DoE test designs such as CCD, CCI as available with the CAMEO DoE test designer option.

A further function in the SOI-Sweep Procedure is the global optimization of legislative emission cycles and an online variation range generator. This permits the variation space to be generated online based on existing ECU maps.