PSI - Issue 12

Francesco Mocera et al. / Procedia Structural Integrity 12 (2018) 213–223 Author name / Structural Integrity Procedia 00 (2018) 000–000

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Fig. 5: Measurements from CAN BUS data.

• the use of a 29 bit identifier for each message; • a standard message length of 8 bytes, with the possibility to send longer messages with a higher level protocol layer; • a standard Baud Rate of 250 kBit / s; The communication protocol has a set of predefined messages identified by the PDU Format and PDU Specific parameters available within the 29 bit identifier. In this work, the main aim was to record some parameters sent in Broadcast periodically by the engine controller to all the CAN BUS controllers available on the network. In particular, the attention focused on the accelerator pedal signal, engine revolutions, engine load and instantaneous fuel consump tion. These parameters were monitored using a CAN BUS protocol analyser inserted in the network. It was set as a monitoring node to avoid any interference with the standard messages flow, thus on the safety of the operations. The experimental activity was done in situ to take notes on the temporal sequence of the working operations. This helped on the post processing analysis of the collected data. The first step to setup the instrumentation consisted of a simple set of known commands. The results of this preliminary activity are shown in Fig. 5. It helped to properly tune the conversion factors of the raw data recorded on the CAN BUS network. As shown in Fig. 5, the thermal engine is controlled in speed due to the strict correlation between the accelerator pedal signal and the measured engine rpm. This control approach is possible thanks to the hydrostatic transmission between the gearbox and the wheels, and to the clutch that disconnects the augers when required. The milling head and 4.2. Experimental results and discussion