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The purpose of this paper is to design a multi-sensory anthropomorphic prosthetic hand and a grasping controller that can detect the slip and automatically adjust the grasping force to prevent the slip.

To improve the dexterity, sensing, controllability and practicability of a prosthetic hand, a modular and multi-sensory prosthetic hand was presented. In addition, a slip prevention control based on the tactile feedback was proposed to improve the grasp stability. The proposed controller identifies slippages through detecting the high-frequency vibration signal at the sliding surface in real time and the discrete wavelet transform (DWT) was used to extract the eigenvalues to identify slippages. Once the slip is detected, a direct-feedback method of adjusting the grasp force related with the sliding times was used to prevent it. Furthermore, the stiffness of different objects was estimated and used to improve the grasp force control. The performances of the stiffness estimation, slip detection and slip control are experimentally evaluated.

It was found from the experiment of stiffness estimation that the accuracy rate of identification of the hard metal bottle could reach to 90%, while the accuracy rate of identification of the plastic bottles could reach to 80%. There was a small misjudgment rate in the identification of hard and soft plastic bottles. The stiffness of soft plastic bottles, hard plastic bottles and metal bottles were 0.64 N/mm, 1.36 N/mm and 32.55 N/mm, respectively. The results of slip detection and control show that the proposed prosthetic hand with a slip prevention controller can fast and effectively detect and prevent the slip for different disturbances, which has a certain application prospect.

Due to the small size, low weight, high integration and modularity, the prosthetic hand is easily applied to upper-limb amputees. Meanwhile, the method of the slip prevention control can be used for upper-limb amputees to complete more tasks stably in daily lives.

A multi-sensory anthropomorphic prosthetic hand is designed, and a method of stable grasps control based on slip detection by a tactile sensor on the fingertip is proposed. The method combines the stiffness estimation of the object and the real-time slip detection based on DWT with the design of the proportion differentiation robust controller based on a disturbance observer and the force controller to achieve slip prevention and stable grasps. It is verified effectively by the experiments and is easy to be applied to commercial prostheses.

Even though multi-rotor aircrafts are becoming more and more prevalent in the fields of aerial photography, agricultural spraying, disaster searching and rescuing, how to achieve higher reliability and robustness of an aircraft still poses a big challenge. It is not a rare case that a multi-rotor aircraft is severely damaged or crushed when an actuator or sensor is malfunctioned. This paper aims at the resilience of an aircraft when a rotor is malfunctioned.

The reliability of a multi-rotor aircraft can be measured in terms of stability, robustness, resilience and fault tolerance. All of these four aspects are taken into consideration to improve overall reliability of aircrafts. When a rotor malfunction occurs, the control algorithm is cable of adjusting the operation conditions of the rest of rotors to achieve system stability.

In this paper, the authors first present a research topic on the development of a resilient multi-robot aircraft. A multi-rotor aircraft usually possesses more actuated motions than the required degrees of freedom.

The authors proposed to equip the multi-rotor aircraft with malfunction detecting sensors, and they developed the self-repairing algorithm to re-stabilize the aircraft when a malfunction of a rotor occurs. The design concept and methods were implemented on an eight-rotor aircraft, and the performance of the proposed instrumentation and self-repairing algorithm have been verified and validated.

In the creation of coal consumption reduction policy, the Chinese Government selected eight provinces as key provinces and encouraged them to replace coal with other non-coal energy, involving Kaldor-Hicks improvement. The purpose of this paper is to answer how much coal can be conserved if Kaldor-Hicks improvement is considered.

A DEA model reflecting Kaldor-Hicks improvement is suggested to calculate the potential of coal reduction, and an endogenous directional distance function model is proposed to calculate the energy consumption efficiency.

The results show that the non-key provinces wasted more coal than the key provinces, although the latter are of more concern. From the Kaldor-Hicks criterion, ten non-key provinces in a certain year can save more coal from an energy substitution policy and eight key provinces cannot. Through measurement of coal and energy efficiency, it is also found that provinces with an abundance of coal perform the worst in China.

Previous studies measuring Chinese saving potential of coal mainly focused on Pareto-Koopmans criterion, not consistent to policy practices. This study changes to Kaldor-Hicks criterion, allowing to make some factors better off and other factors worse off.

The purpose of this study is to enhance audience experience in museum by using three-dimensional (3D) virtual simulation technology.

In this study, a large space museum building tourism demonstration system based on 3D virtual simulation technology was proposed. Starting from the concept of virtual reality (VR), the characteristics of VR and the classification of VR systems were introduced, and the research status of VR technology at home and abroad and the application of 3D virtual simulation were discussed. Then the key technologies of 3D modeling, 3D scene optimization and 3D simulation driving of 3D virtual simulation were expounded, and the characteristics and application scope of different technical methods were analyzed. Finally, an example of the Hongzhou Kiln 3D network museum was listed.

The research results showed that 3D virtual simulation has a wide range of applications in the field of VR. Different elements need to be considered for different types of applications, and different contents need to be integrated to achieve the corresponding interaction modes.

Virtual image; multimedia; large space museum; tourism demonstration system; 3D virtual simulation technology.