Bulk handling grabs are often used for unloading bulk materials such as iron ore and coal from bulk carrying ships. To improve and compare virtual simulations of new grabs, accurate real life kinematic data of grabs is required. Moreover kinematic data can potentially provide ins
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Bulk handling grabs are often used for unloading bulk materials such as iron ore and coal from bulk carrying ships. To improve and compare virtual simulations of new grabs, accurate real life kinematic data of grabs is required. Moreover kinematic data can potentially provide insight in current use of grabs, which can be interesting information for both manufacturer and customer of the grab. The possibilities towards implementation of a sensor system on bulk handling grabs are investigated by selecting a suitable sensor and measuring kinematics and operations of imitated grab movements. This research focuses on investigating kinematics of multi rope grabs with dual scoops. A sensor selection procedure is followed resulting in the selection of an Inertial Measurement Unit (IMU) sensor with Global Navigation Satellite System (GNSS) receiver. In several experiments the sensor data is compared with reference data of imitated grab movements assumed as ground truth. When using multiple IMU’s (one on each grab scoop) providing orientation data, the opening angle can be determined. The results of the experiments indicate that the position data provided by the sensor can be used for classification of activities, but less for high precision movement trajectory reconstruction. Position and orientation data of imitated grab movements can be interpreted to generate performance indicators that describe grab operations. Experiments showed that performance indicators of imitated grab movements can be identified accurate up to an error of two seconds when comparing known performance indicators and sensor data analysis. When a high level of accuracy of the kinematic data is reached, performance indicators describing grab operations can be determined more accurately.