# Motion Generation for Crane Simulators Using Streamlined Motion Blending Technology
## 1 Introduction
proposed a motion generation approach based on the motion blending technology [24, 25], which seems to be methodologically applicable to solve the crane motion perception simulation problem. According to this approach, regeneration of the motions perceptible to operators on the simulator can be divided into two steps. The first step is to generate a motion flow, and the second step is to apply a wash out algorithm to the motion flow to ensure that the motion could be realized on the motion platform on the premise of motion perception similarity. The main contributions of this approach mainly lie in the first step, and the second step is a direct application of the typical wash out algorithm. The whole motion bulk data are divided into some motion blocks which are stored in the database. In real-time simulation, a natural motion stream is generated by optimally synthesizing a set of motion blocks retrieved from the database to reflect the current simulation conditions and user demands [24]. In the process of searching and synthesizing optimal motion blocks, vehicle dynamics-based parameterization can also be included in the work flow to make the motion blending approach more effective by combining dynamics-driven motion and data-driven motion in a hybrid way [25]. Since the motion block concept is not applicable to the crane motion simulation, the motion generation approach based on motion blending technology only provides a possible clue for current study. In summary, on the one hand, all the current crane simulators are highly in need of being enabled with more realistic motion simulation, while on the other hand, the traditional motion cueing algorithm widely used in vehicle simulators or other similar areas should have little usefulness if plainly exploited without radical improvements. This motivates the current study to develop a novel motion generation approach dedicated to motion perception simulation for quayside container cranes. The approach developed is based on the streamlined motion blending technology, which is an improvement to the motion generation algorithm based on the motion blending technology proposed by [PERSON] et al. The improvements are reflected in two aspects. Firstly, 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. Secondly, each motion component either directly acts as the driving command of the motion platform without subsequent washout processing, or directly incorporates the washout algorithm effects into the models. It is noted that the proposed streamlined motion blending technology used for motion generation for crane simulators has many advantages for implementation. Two steps of modeling and calculation tasks are now combined into one task. Redundant data conversion links are eliminated. The technical realization route is more concise and clearer. The calculation workload is greatly reduced and finally allows for the achievement of more realistic simulation effects and higher fidelity of motion perceptions. Experiments are conducted to verify the effectiveness of the proposed motion perception simulation approach based on streamlined motion blending technology. The rest of this paper is organized as follows. Section 2 analyzes the characteristics of the crane motion from the view point of the motion perception and overviews application of conventional motion generation technologies for crane simulators. Section 3 elaborates the proposed streamlined motion blending technology for crane motion simulation. Section 4 describes modeling of typical motion components. System implementation and application effect evaluation through experiments are reported in Section 5. Finally, in Section 6, concluding remarks are drawn and future research directions discussed.