# Motion Generation for Crane Simulators Using Streamlined Motion Blending Technology
## 6 Conclusions  
In this paper, a motion generation approach for a crane simulator is proposed based on streamlined motion blending technology. This approach incorporates the characteristics of the perceptible motion of a crane, which are decomposed into two types of motion components, i.e., high-frequency small-scale vibrations and low-frequency large-scale movements. At the moment when each motion component constituting the motion is generated, it is directedly modeled or modeled with an immediate conversion applied. Specifically, for the motion component of high-frequency small-scale vibrations, it is modeled according to crane dynamics and remains unchanged without the need for motion washout processing. For the motion component of low-frequency large-scale movements, the real motion mode is firstly defined and then immediately converted into another equivalent motion component according to the principle of the motion washout algorithm. After the motion components are identified and handled adequately in this way, they are then blended together to form a coherent motion stream to drive the platform. The effect of the motion generation algorithm based on this approach is exactly the same as the processing method deduced according to the existing motion blending technology combined with the classical washout algorithm. However, the current algorithm eliminates multiple redundant filtering tasks, and thus is more efficient and smoother. The computational workload is greatly reduced, and the real-time performance is stronger.  
By taking a concrete motion simulator of the quayside bridge crane as an example, the proposed motion generation approach based on the streamlined motion blending technology is implemented in detail. The general algorithm design of the complete motion perception simulation system, as well as the modeling of each motion component, is carried out. Related decisions are considerately made to select the appropriate motion platform and other hardware facilities. Apart from the motion generation system, the prototype system developed also includes a visual system. An experimental verification study is conducted by inviting skilled driver volunteers. The experimental results show that the developed prototype system has high motion fidelity, and this high-fidelity motion performance helps to improve the training effect of the simulator in training new crane drivers.  
The crane motion simulation method based on streamlined motion blending technology has a wide range of generality. It is not only suitable for the quayside container bridge crane simulator as an application example in this paper, but is also suitable for other types of cranes and various construction machinery. Once the motion simulation method proposed in this paper is extended to other engineering machinery simulators, the  
Figure 16: Column chart of controlled subjective evaluation test results.  
corresponding models and algorithms can be developed accordingly. It is finally expected to provide trainees with a more realistic motion perception effect in this way and thus create more application value.  
Conceptualization, Z.Z., Y.L., H.X. and G.W.; methodology, Z.Z. and G.W.; software, Z.Z. and G.W.; validation, Z.Z., Y.L., H.X., Z.L., C.X. and G.W.; formal analysis, Z.Z. and Y.L.; investigation, Z.Z. and Y.L.; resources, Z.Z., Y.L., H.X. and G.W.; data curation, Z.Z. and Y.L.; writing--original draft preparation, Z.Z., H.X. and G.W.; writing--review and editing, Z.Z., Y.L., H.X., Z.L., C.X. and G.W.; visualization, Z.Z. and G.W.; supervision, Z.Z., Y.L., H.X., Z.L., C.X. and G.W.; project administration, Z.Z., Y.L., H.X., Z.L., C.X. and G.W.; funding acquisition, Z.Z., Y.L., H.X., Z.L., C.X. and G.W. All authors have read and agreed to the published version of the manuscript.  
This research received no external funding.  
Not applicable.  
Data Availability Statement: Data are contained within the article.  
The authors declare no conflict of interest.