In crane safety assessment, both quantitative and qualitative indicators are inevitably influenced by the subjective influence of the evaluator, which is unfavorable to the objective requirements of safety assessment. In response to these problems, this study proposes a crane safety assessment method based on the cloud model and the improved combination weighting method of game theory (ICWGT). This evaluation method constructs a multi-level assessment index system for crane safety status by selecting suitable indicators in layers and groups, according to the crane safety assessment rules, and gives a method for constructing the cloud model of the commentary set, the selection and derivation of the membership function, and the determination of the fuzzy relationship matrix. When performing fuzzy synthetic calculations based on the cloud model, the synthetic operator enhances the effect of expectation on entropy and makes the cloud image significantly deformed; this method uses a fine-tuned synthetic operator to improve the algorithm. Compared with the traditional crane fuzzy synthesis assessment method, this method combines the cloud model and ICWGT to achieve finding a balance between expert experience and sample data information, calculating the combined optimization weights of each index and component layer by layer. In order to verify the effectiveness of the method, we take the metal structure system of the shipyard portal crane as an example to explore the applicability of the method in crane safety assessment. The results show that the assessment method can accurately reflect the safety level of the crane and can provide reference material for crane safety assessment.

For development of a simulator with a motion platform to generate an appropriate motion to reproduce the motion sense for the users, one of the most significant but disregarded complicated tasks is to build up a dynamic virtual motion model to reflect the motion of the simulated object in the corresponding physical world. Recently, a motion generation method based on motion blending technology was developed to alleviate the complication involved. It decomposes the simulated motion into a great number of parameterized motion blocks which are depicted by real motion data acquired from field tests and stored in a database. This paper proposes a streamlined motion blending technology suitable for a container crane simulator to further improve the current motion generation method based on the motion blending technology. Motion components, rather than motion blocks specially marked and stored in a database, are taken as the basic motion unit easily acquired through united analysis of crane dynamics and motion perception characteristics. They are then blended on demand to produce a one-stop model to directly act as the driving command of the motion platform without the need for a subsequent dedicated wash-out procedure. The calculation workload is greatly reduced and finally allows for achievement of higher fidelity of motion perceptions. Experiments are conducted to verify the effectiveness of the proposed streamlined motion blending technology for motion perception generation. Better training effect is found to be achieved due to more realistic simulation effects. The comprehensive training effectiveness index is enhanced from 54% to 82% once a motion simulation system developed using the proposed approach is introduced into the crane simulator.