System and method for machine load detection

A machine, comprising:

• a frame that supports an engine connected to a transmission, the transmission selectively transforming an input engine speed and engine torque to an output transmission speed and transmission torque, the transmission speed and torque being applied to a set of ground engaging members to propel the frame;
• a transmission output speed (TOS) sensor disposed to provide a signal indicative of a speed of an output of the transmission;
• a controller configured to control operation of the engine and the transmission based on a desired torque output of the transmission by, at least in part, estimating an actual torque output of the transmission and using the actual torque estimation as a control feedback;
• wherein the controller is further configured to:
• determine, in real time, a first TOS based on the signal provided by the TOS sensor,
• calculate a first acceleration based on the first TOS;
• determine a second acceleration based on at least one of engine speed, engine torque, machine inertia, and on a transmission setting;
• determine a divergence between the first and second accelerations;
• calculate a rate of change of the divergence between the first and second accelerations;
• and
• when the rate of change of the divergence exceeds a threshold value, adjust a control parameter that adjusts the transmission setting to avoid a decrease in engine speed below a threshold engine speed value.

A method for operating an electronic controller for detecting transient torque changes in a torque-controlled transmission, the electronic controller configured to control operation of the torque-controlled transmission, the method comprising:

• operating the electronic controller to monitor a transmission output speed (TOS) sensor signal indicative of an output speed of the transmission;
• determining a first TOS acceleration by calculating a derivative of the measured TOS in the electronic controller based on the TOS sensor signal;
• operating the electronic controller to estimate a torque at an output of the transmission;
• operating the electronic controller to determine a second TOS acceleration by dividing the estimated torque by a predetermined inertia of the machine using the electronic controller;
• comparing the first and second TOS accelerations in the electronic controller and, when a parameter based on a difference between the first and second TOS accelerations exceeds a threshold value, causing the electronic controller to activate a torque transient change trigger.