Automatic Trajectory Tracking Research Articles

Determination of thrusts for different cylinder groups during shield tunneling

The hydraulic thrust system that emphasizes grouped controlling of the shield machine is used for driving forward and pose adjustment. To control and regulate the pose of the shield machine precisely, it is of great significance to solve the total thrust and grouped thrusts (thrusts for different cylinder groups) reasonably. This study aims to develop a novel thrust model to calculate the total thrust and grouped thrust. Firstly, a soil-machine interaction model is developed to predict the loads acting on the shield machine during tunneling. Then an inverse kinematic analysis is performed to describe the velocity Jacobian and soil displacement induced by pose adjustment. Based on the kinematic mechanism of the shield machine under soil resistance, a thrust model is proposed to determine the total thrust and grouped thrusts employing static mechanics. In this model, both the soil properties and the shield parameters, such as operating parameters, pose parameters and geometric parameters are considered. The proposed thrust model is verified through a case application and the results indicate that the model could be used for assessing the total thrust and grouped thrusts during shield tunneling, which provides a theoretical basis for pose adjustment and automatic trajectory tracking control of the shield machine.

Kinematic Analysis and Virtual Prototype Simulation of the Thrust Mechanism for Shield Machine

The hydraulic thrust system of the shield machine is used for driving forward and pose adjustment. It is of great significance to figure out the thrust mechanism and motion characteristics of the shield machine to ensure the safety of tunnel excavation. This study aims to develop a model to explore the influence of thrust cylinder advancement on the motions of the shield machine. Firstly, the study carried out mechanism analysis of the thrust mechanism for the shield machine and established a method to describe the position and attitude of the shield machine during the tunneling process by the homogeneous transformation matrix. Then, a new inverse kinematic model was proposed to quantify the relationship between the telescoping movements of cylinders and shield machine motions, and the Jacobian matrix was derived to solve the instantaneous kinematics analysis. Furthermore, a virtual prototype model was developed to simulate the kinematic behavior of the shield machine and validate the accuracy of the kinematic model. The model provides the basic constraint relations for the practical position control system and lays a strong foundation for the dynamic model and automatic trajectory tracking control of shield machines for future studies. Based on the proposed model, the displacement, velocity, and acceleration of cylinders that drive the shield machine to the target motions can be solved exactly. It can provide a reference for the pose control of the shield machine during the practical shield tunneling.

Automatic Tracking Method of Basketball Flight Trajectory Based on Data Fusion and Sparse Representation Model

The appearance model of flying basketball obtained by the traditional basketball flight trajectory tracking method is not accurate, which leads the anti-interference performance of trajectory tracking not ideal. Based on data fusion and sparse representation model, a new automatic trajectory tracking method is proposed. Firstly, the relevant technologies of basketball flight trajectory automatic tracking are studied and summarized, and then the method is studied. The specific implementation steps of this method are as follows: the features of flying basketball images were extracted by the target feature extraction algorithm, and the appearance model of flying basketball was built based on sparse representation. Data fusion technology and particle filter algorithm are combined to realize automatic tracking of basketball flight path. Through three axial basketball trajectories of automatic tracking test and noise test and verify the design method under the 3D world coordinate system to achieve the X, Y, and Z axis up more accurate tracking, at the same time, after applying measurement signal to noise, automatic trajectory tracking results affected by some, but still managed to realize the trajectory tracking.

DeepGTT: A general trajectory tracking deep learning algorithm based on dynamic law learning

Deep learning technology provides novel solutions for increasingly complex target tracking requirements. For traditional target tracking models, the movement of the target need to be simulated by a predefined mathematical model. However, it is extremely difficult to obtain sufficient information in advance, which makes it challenging to track changeable and noisy trajectories in a timely and precise manner. A deep learning framework is constructed for automatic trajectory tracking based on learning the dynamic laws of motion, called DeepGTT. Specifically, a trajectory generator and a trajectory mapper were designed to standardise trajectory data and construct trajectory mapping, which enable the long short-term memory–based tracking network to learn general dynamic laws. Then, to discuss the interpretability of the model, the mechanism of the deep learning framework is considered and a memory factor matrix is defined. Finally, extensive experiments are conducted on various weak manoeuvring and manoeuvring scenarios to evaluate the algorithm. Experimental results demonstrate that the DeepGTT algorithm remarkably improves accuracy and efficiency compared with most conventional algorithms and state-of-the-art methods. In addition, interpretability experiments qualitatively prove that the tracking network can perceive dynamic laws when estimating the target state.

Longitudinal and lateral control for four wheel steering vehicles

Vehicles evolving in harsh terrains are subject to physical phenomena with a much more important impact than in the case of road vehicle. The main problem we have to face is tire slippery which has to be taken into account when designing the control law to ensure an accurate tracking. In this paper we present a controller for cars equipped with 4 steering wheels. An accurate automatic trajectory tracking via vehicle wheel torque, front and rear steering is developed. This controller takes into account nonlinear tire effects to increase vehicle stability in presence of sliding. Promising results have been obtained with numerical simulations.

JumpDetector: An automated monitoring equipment for the locomotion of jumping insects.

Continuous jumping behavior, a kind of endurance locomotion, plays important roles in insect ecological adaption and survival. However, the methods used for the efficient evaluation of insect jumping behavior remain largely lacking. Here, we developed a locomotion detection system named JumpDetector with automatic trajectory tracking and data analysis to evaluate the jumping of insects. This automated system exhibits more accurate, efficient, and adjustable performance than manual methods. By using this automatic system, we characterized a gradually declining pattern of continuous jumping behavior in 4th‐instar nymphs of the migratory locust. We found that locusts in their gregarious phase outperformed locusts in their solitary phase in the endurance jumping locomotion. Therefore, the JumpDetector could be widely used in jumping behavior and endurance locomotion measurement.

Mechatronic design and implementation of a two axes sun tracking photovoltaic system driven by a robotic sensor

In the study presented in this paper , the problem of the design and implementation of a two-axis sun tracking system was addressed by applying a set of two robotic systems, one for the automatic orientation of the photovoltaic modules and the second for providing the reference trajectory (robotic sensor). The design methodology was based on mechatronic concepts, in particular the VDI 2206 standard, according to which the system is divided into interconnected modules to be designed, validated, and integrated. This approach provides an efficient energy collection system in terms of the mechanism, instrumentation system, energy supply, and automatic trajectory tracking control. Experimental results illustrate the behavior of the proposed system, which achieves a better performance than fixed systems, as well as one-axis tracking mechanisms.

An Internal Model Control (IMC) Algorithm for Automatic Trajectory Tracking

This paper presented a trajectory tracking algorithm applied for an intelligent driving system. Both the path tracking and longitudinal speed tracking controller are based on IMC algorithm and are carried out respectively. A simulation tool is introduced in this paper and some simulation tests were conducted to verify the proposed trajectory planning algorithm. The simulation results show that the proposed trajectory tracking algorithm is valid and good for the applications of vehicle driving in complex environment.

Automatic trajectory tracking control of shield tunneling machine under complex stratum working condition

Automatic trajectory tracking control is a significant task of thrust system during tunnel excavation. Tasks of steering and posture adjustment of the shield machine can be achieved by properly adjusting the distribution of thrust pressure in corresponding working zones. Principle of hydraulic thrust system and hydraulic load simulation test rig of shield machine are illustrated at first. Then a set of scientific and complete orientation and posture rectification strategies has been put forward to eliminate the position and angle deviations simultaneously. Based on construction site investigation, mechanical structure diagram and kinematics model of the thrust system have been established. Then, the numerical results of path planning under steering or rectifying working condition are demonstrated. An integrated control system, which consists of one trajectory planning controller for both cylinders and an individual cylinder controller for each of hydraulic cylinders, is proposed to achieve the automatic control of the thrust trajectory. A cascade control strategy, which comprises feedforward controller of fixed-value compensation and feedback controller of Variable-gain proportion–integration–differentiation (PID), is applied to achieve the precise tracking control of the given trajectory. Experimental studies on automatic trajectory tracking control under several typical working conditions are done at last.

Theoretical Analysis and Experimental Study on Automatic Trajectory Tracking Control of a Shield Tunneling Machine under Pressure Regulation Working Mode

Hydraulic thrust system is a critical part of shield tunneling machine. Automatic trajectory tracking control is a significant task of thrust system during tunnel excavation. In this article, plane mechanical structure diagram of the thrust system and path planning method are illustrated at first. An integrated control system is proposed to achieve the automatic control of the thrust trajectory. The control system consists of one trajectory planning controller for both cylinders and an individual cylinder controller for each of hydraulic cylinders. Trajectory planning controller is used to generate respective displacement signals of double-cylinder in every thrust stroke and each of cylinder controllers is used to realize the precise control of the given thrust trajectory. Variable-gain PID control strategy applied to achieve the precise tracking control of thrust trajectory under several typical working conditions are done at last. The experimental results demonstrate that variable-gain PID control have good performances with short response time and small overshoot regardless of changes of working conditions.

Neuro Robust Adaptive Descending Control of Space Vehicles

Accurate descending control is crucial to ensure safe operation of space exploration vehicles. This work investigates automatic trajectory tracking control of space vehicles during landing phase. A set of algorithms for adjusting vehicle heading angle, heading speed and altitude are derived using adaptive robust and neural network control techniques. It is shown that with the proposed control algorithms, external disturbances and coupled dynamics inherent in the system are effectively compensated. Simulations on various flight conditions also confirm the effectiveness of the proposed methods.