Taixiong Zheng

Extended-State-Observer-Based Double-Loop Integral Sliding-Mode Control of Electronic Throttle Valve

An extended-state-observer-based double-loop integral sliding-mode controller for electronic throttle (ET) is proposed by factoring the gear backlash torque and external disturbance to circumvent the parametric uncertainties and nonlinearities. The extended state observer is designed based on a nonlinear model of ET to estimate the change of throttle opening angle and total disturbance. A double-loop integral sliding-mode controller consisting of an inner loop and an outer loop is presented based on the opening angle and opening angle change errors of ET through Lyapunov stability theory. Numerical experiments are conducted using simulation. The results show that the accuracy and the response time of the proposed controller are better than those of the back-stepping and sliding mode control.

Multi-robot task allocation and scheduling based on fish swarm algorithm

The problem of multi robot task allocation and scheduling is to assign more relative tasks to less relative robots and to scheme task processing sequence so as to minimize the processing time of these tasks. The key of this problem is to allocate proper quantity of tasks for each robot and schedule the optimal task sequence for each robot. In order to minimize the processing time for robots, an optimized multiple robots task allocation and scheduling approach based on fish swarm algorithm is proposed. In this approach, the optimized task sequence is first schemed using fish swarm algorithm on the assumption that all the tasks are processed by one robot. Then, according to the number of the robots, the task sequence has been randomly divided into several task segments that will be assigned to robots. At last, the task numbers of each task segments are averaged according to the time each robot used, therefore proper quantity of tasks is allocated to each robot and the optimized task allocation scheme is got. To validate the effectiveness of the proposed approach, experiments and simulation have been made. The results show that the proposed approach can scheme optimized multi robots task allocation and scheduling scheme.

Extended State Observer Based Adaptive Back-Stepping Sliding Mode Control of Electronic Throttle in Transportation Cyber-Physical Systems

Considering the high accuracy requirement of information exchange via vehicle-to-vehicle (V2V) communications, an extended state observer (ESO) is designed to estimate the opening angle change of an electronic throttle (ET), wherein the emphasis is placed on the nonlinear uncertainties of stick-slip friction and spring in the system as well as the existence of external disturbance. In addition, a back-stepping sliding mode controller incorporating an adaptive control law is presented, and the stability and robustness of the system are analyzed using Lyapunov technique. Finally, numerical experiments are conducted using simulation. The results show that, compared with back-stepping control (BSC), the proposed controller achieves superior performance in terms of the steady-state error and rising time.

An extended microscopic traffic flow model based on the spring-mass system theory

This study proposes a new microscopic traffic flow model based on the spring-mass system theory. In particular, considering the similarity between the acceleration or deceleration behavior in traffic flow and the scaling properties of a spring, a car-following (CF) model is proposed based on the fundamental physical law of the spring-mass system. Stability of the proposed model is analyzed using the perturbation method to obtain the stability condition. Numerical experiments are performed through simulation. The results demonstrate the proposed model can capture the characteristic of propagation backwards of disturbance in traffic flow. In addition, the findings of this study provide insights in modeling traffic flow from the mechanical system theory perspective.

DSRC based vehicular platoon control considering the realistic V2V/V2I communications

This study proposes a dedicated short range communications (DSRC) based vehicular platoon control considering the realistic vehicle-to-vehicle/vehicle-to-infrastructure (V2V/V2I) communications. In particular, the information on vehicles of interest, i.e., speed and position, is shared with the neighboring vehicles or roadside units (RSUs) through the on-board units (OBUs) via the DSRC. Then, the leader-follower approach is used to manage the vehicular platoon. The leader of platoon can receive/send the relevant information from/to the followers so as to guarantee the stable platoon formation. Field experiments are performed in two scenarios: platoon forming and merging. Results from the experiments validate the effectiveness of the proposed method in terms of the speed and position trajectories.

TransModeler based implementation of autonomous vehicular platoon control

This study develops a vehicular platoon control system (VPCS) based on the combination of car-following model and leader-follower model under connected environment. In particular, first, a three-level framework including information collection, information processing and information release is proposed to design the control strategy. Then, the car-following model is used to capture the characteristics of vehicular platoon movement; while the leader-follower model is used to describe the vehicle dynamics of vehicle merging into the platoon. Finally, the TransModeler based platform is developed to validate the effectiveness of the proposed method with respect to vehicle speed and position trajectory.

Misfire detection based on switched state observer of hybrid system in internal combustion engine

This paper proposes a novel switched state observer of hybrid system using Luenberger sliding mode observer to estimate crankshaft angular acceleration which is further applied to detect misfire fault. The output error of hybrid system of internal combustion engine (engine speed) and the designed observer (estimated speed) is taken as input of observer to estimate crankshaft acceleration. Convergence of hybrid system is proven through Lyapunov stability theory. The experimental results show that the presented estimated technique has a higher accuracy and can be effectively used to misfire detection compared with reduced-order observer and sliding mode observer.

Luenberger-sliding mode observer based ammonia concentration estimation for selective catalyst reduction system

This paper presents a Luenberger-sliding mode observer to estimate selective catalyst reduction (SCR) system mid-catalyst ammonia concentration. In order to measure the ammonia concentration at the middle of the catalyst, a two-cell SCR model was utilized. The robustness of the observer with respect to sensor measurement uncertainties were theoretical analyzed. And the stability of the observer was shown based on the sliding mode approach. The performance of the observer was validated on the simulation platform. Simulation studies showed that the proposed observer had a good robustness and tracked the target ammonia concentration very well. And the two-cell SCR system had potential to lead to a higher NOx conversion percentage.

Fault diagnosis of internal combustion engine valve clearance: The survey of the-state-of-the-art

There are a lot of research activities on developing technique to detect internal combustion engine valve clearance faults. These faults decrease the performance, the reliability and the efficiency of internal combustion engine drive system. In this work, we introduced the development of internal combustion engine valve clearance diagnosis, analyzed the advantages and disadvantages of some methods about feature extract and fault diagnosis, and summarized some important issues on the development of fault diagnose of internal combustion engine valve clearance, and put forward a deeper view investigated in the future.

Study of fuel film parameter identification in gasoline engine transient conditions based on weighted recursive instrumental variable method

It is very important for transient air-fuel ratio control to obtain the fuel film dynamic parameters precisely. The fuel film identification equation based on the inlet fuel film dynamic model is built under the consideration of random errors. In order to eliminate the effect of random errors on the fuel film parameter estimation, instrumental variable (IV) method is put forward. At the same time, considering that each set of measurement data have different confidence coefficient in terms of parameters estimation, the weighted term is introduced to the instrumental variable equation. An engine model is set up using EN-DYNA. Parameter identification applying the proposed algorithm, least squares and Markov recursive least squares are conducted respectively at 1500-3000r/min and the throttle opening from 10%-80%. The identification results are compared and analyzed with the calibration value. The results show that maximum deviation of X and τ applying the weighted recursive instrumental variable method are 1.58% and 4.5% respectively. However, the maximum deviation of X and τ are 2.37% and 6.18% in Markov recursive least squares method meanwhile the value are 4.08% and 9.16% in least squres method.