As an important technical basis of predictive maintenance,lifetime prognostics has been paid more and more attention in recent years.Real-time reliability evaluation and prediction is an effective solution to lifetime prognostics.This paper summarizes the real-time reliability evaluation and prediction methods for engineering systems,and investigates some applications of these methods.Some open problems in this field are also discussed,and future research directions are pointed out.

A new sensor-based obstacle avoidance and path planning algorithm for mobile robots is proposed.The field-of-view(FOV) constraint of sensors is considered,and only the local information of the environment in a single FOV is used.Two searching modes are employed to find a safe path in the current FOV,given the current moving direction,data of obstacle boundary endpoints and the orientation of the target.The two modes ensure the convergence to the target of the path.Simulations results demonstrate the effectiveness of the algorithm proposed.

The on-board computer(OBC) that controls a manned spacecraft must be extremely reliable.Such a computer system generally has the ability of Byzantine fault resilience.Based on the theory of Byzantine resilience,a conceptual design of the Byzantine fault tolerant computer implementation is proposed.The feasibility of this scheme is validated in the real system through experiments.

In this paper,the issue on fast attitude maneuver control of a spacecraft with flexible appendix is studied.The characteristic model is derived based on the dynamics model of the spacecraft with flexible appendix.A characteristic model based adaptive control method is proposed which can achieve the fast attitude maneuver and vibration attenuation simultaneously.The controller is simple to design with explicit physical meanings on its design parameters and ease of the controller tuning.Both theoretical analysis and computer simulation show that the method proposed in this paper has good robust stability and robust performance to both varying controller parameters and plant uncertainties.Comparison with the traditional proportional-derivative(PD) control method shows that the adaptive control method proposed is superior to PD control in achieving faster attitude maneuver and vibration attenuation of the flexible spacecraft.

　According to requirements for mechanical environment tests of spacecraft products,static analysis,modal analysis,dynamic analysis such as shock response,sine vibration and random vibration for a CCD star sensor are made by the finite element analysis(FEA) software MSC.NASTRAN in this paper.And FEA thermal analysis is useful to better design of the mounting bracket for the cube.