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Interactive design is a comprehensive discipline that integrates multidisciplinary knowledge. It emphasizes the comprehensiveness and timeliness of the curriculum, strengthens the consistency between disciplines and design science, such as psychology, computer science, and literature, and enhances the relevance of each other. Interactive design not only needs support of the professional curriculum knowledge such as visual communication design, modeling design, structural design and product design, but also the support of cross-professional knowledge such as sensor principle, C language programming and mechanical principle. In the curriculum system of interactive design, the curriculum needs to be easy to difficult and gradually promoted. It should pay equal attention to the knowledge logic structure and development process, the longitudinal development and horizontal development of knowledge, and the theoretical knowledge teaching and innovation practice ability. With the dynamic-cycle system of theory-practice-theory-re-practice, a perfect knowledge structure of interactive design for students.

For the trajectory tracking control problem of rigid hydraulic manipulators under heavy uncertainties and nonlinearities, a novel fractional-order nonsingular terminal sliding mode (FO-NTSM) control method based on time-delay estimation (TDE) is proposed. The proposed control scheme mainly contains two parts: a TDE term and a FO-NTSM term. The TDE term is applied to approximately cancel the complex system dynamics using the intentionally time-delayed information leading to an attractive model-free nature. Meanwhile, the FO-NTSM term, based on a novel fractional-order terminal sliding surface, is designed to stabilize the tracking error to zero in finite time. Stability of the closed-loop control system is analyzed based on the Lyapunov stability theory. Finally, comparative degrees of freedom (2-DOF) practical experiments are performed and the results show that the new proposed method can ensure faster convergence rate and higher tracking precision under heavy lumped uncertainties and nonlinearities compared with its integer-order counterpart.

In this paper, the adaptive robust control method with a velocity observer is proposed to control a deep-sea manipulator. The parametric uncertainties and external disturbances make the linear controller invalid, and hydraulic actuator’s dynamics can’t be neglected because hydraulic system’s complex nonlinearity might lead to vibration. To solve the problem, an adaptive robust controller which can also compensate the interactive dynamic effects between manipulator links is developed. The deep-sea manipulators are only installed with angular sensors, so an observer providing the smooth angular velocity estimation is designed. By using the Lyapunov approach, the proposed controller can be proved asymptotically stable for trajectory tracking. The contrast experiments are conducted on a deep-sea hydraulic manipulator, experiment results show the control algorithm could provide a fast, high accuracy tracking, and guarantee the tracking performance when subjected to payload change or a range of different reference signals.Copyright © 2015 by ASME

In this paper, design and experiments of the 4500m deep-sea manipulator are introduced. With the extreme working condition, the deep-sea manipulator is more complex and the study is more challenging. The design highlight is stressed, including the double screw pairs elbow joint which could transmit large torque with a compact size, principle of pressure compensator which could balance the water pressure and so on. To achieve high tracking performance, the adaptive robust tracking control based on backstepping algorithm is proposed. The unknown parameters are estimated to enhance the tracking precision. Simulations and experiments based on this algorithm has been performed to verify the controller, the results show that the joint tracking control is fast and smooth, the overshot is small.

In this paper, a nonsingular terminal sliding mode (NTSM) control method based on time delay estimation (TDE) is proposed and investigated for the depth control of remotely operated vehicles (ROVs). The complex dynamics is approximately compensated by TDE leading to an attractive model-free nature, which is more suitable for practical applications than other model-based methods. Furthermore, the NTSM manifold based on nonlinear error dynamics can ensure better control performance than the traditional sliding mode (SM) manifold with linear error dynamics. Stability of the closed-loop system is analyzed using Lyapunov theory. Finally, the faster convergence and higher tracking accuracy compared with traditional TDE method with linear error dynamics are verified through simulation.

This paper is based on the current problems existing in the interaction design teaching. It describes the significance of interaction design studio teaching and discusses the construction of it from five aspects: the platform of school- enterprise cooperation, studio set, project team, project curriculum and teaching management. It is hoped that this paper may provide some insights for the development of interaction design studio teaching in China.

A robust adaptive control method with full-state feedback is proposed based on the fact that the elbow joint of a seven-function hydraulic manipulator with double-screw-pair transmission features the following control characteristics: a strongly nonlinear hydraulic system, parameter uncertainties susceptible to temperature and pressure changes of the external environment, and unknown outer disturbances. Combined with the design method of the back-stepping controller, the asymptotic stability of the control system in the presence of disturbances from uncertain systematic parameters and unknown external disturbances was demonstrated using Lyapunov stability theory. Based on the elbow joint of the seven-function master-slave hydraulic manipulator for the 4500 m Deep-Sea Working System as the research subject, a comparative study was conducted using the control method presented in this paper for unknown external disturbances. Simulations and experiments of different unknown outer disturbances showed that (1) the proposed controller could robustly track the desired reference trajectory with satisfactory dynamic performance and steady accuracy and that (2) the modified parameter adaptive laws could also guarantee that the estimated parameters are bounded.

The hydraulic propulsion system is widely used in underwater vehicles due to its high power density and good control performance. In this paper, a torque-controlled hydraulic propulsion system which consists of a pump, a couple of proportional pressure reducing valves and a thruster driven by a hydraulic motor is presented. It has a much lower cost and a higher efficiency compared with servo valve control systems. And its response is still quick enough to control the underwater vehicles’ attitude compared with secondary regulation systems. However, while the propeller is running at a low shaft speed, its load characteristics may lead to instability due to its low load stiffness at low speed, low friction and small internal leakage inside the hydraulic motor. In this paper, all these hydraulic parameters, even the fluid viscosity and the effective bulk modulus, which may influence its stability, are all analyzed and simulated. Based on this, a drive-pressure and back-pressure independent regulation control method is proposed. Pool experiments shows that this double pressure regulated hydraulic propulsion system is quite stable and reliable at low shaft speed.

To optimize the umbilical line design of the Offshore Subsea Christmas Tree Control System (OSCTCS) and reduce its cost, a mathematical lumped parameter model of the umbilical is developed. Taking advantage of the intermittent flow-rate need of the OSCTCS and the hydraulic capacitance compensation effect of the long umbilical lines between the Hydraulic Power Unit (HPU) and the Subsea Control Unit (SDU) combining with a subsea accumulator to compensate the decrease of umbilical's flow capacity, an offshore hydraulic system design method is presented. The study results show that the instantaneous equivalent hydraulic resistances of the umbilical are reduced and the combination of the hydraulic capacitance and the accumulator capacitance could enhance the umbilical's flow capacity which would optimize the umbilical design.