Abstract: A torque estimator is disclosed for estimating torque on a machine. A computer system may include a torque estimator module located on the machine. The torque estimator module may be configured to receive a plurality of engine parameters, receive a drivetrain component parameter, determine an estimated torque value at the drivetrain component based on the plurality of engine parameters and the drivetrain component parameter. The computer system also may include an analysis module located on the machine. The analysis module may be configured to receive the estimated torque value and the drivetrain component parameter, and update a histogram data structure based on the estimated torque value and the drivetrain component parameter. The analysis module may also be configured to evaluate the histogram data structure in order to determine if excessive torque is being applied to a drivetrain component.

Abstract: Individual cylinder output deviations from a normal operating engine cylinder are detected via an analysis of crank shaft speed fluctuations. In the detection phase, the engine is operated at a steady state low idle condition, and engine speed data is collected over a plurality of engine cycles. This data is then averaged, filtered and compared to expected engine speed data. A substantial deviation from the expected speed data in the region of crank shaft angles associated with an individual cylinder during its power stroke adjacent its top dead center position indicates a power level deviation in that cylinder. The magnitude of the power level deviation can then be assessed through a similar procedure where engine speed data is collected, averaged, filtered and compared to expected engine speed data when the engine is operating in a steady state rated condition.