Clutch Control Research Articles

Automatic clutch control using ADRC with continuous adaptive extended state observer

Automatic clutch control using ADRC with continuous adaptive extended state observer

Skill assessment based on clutch use in cross-platform robot-assisted surgery.

Many studies have investigated the transfer of skills between laparoscopic and robot-assisted surgery (RAS). These studies have considered time, error, and clinical outcomes in the assessment of skill transfer. However, little is known about the specific operations of the surgeon. Clutch control use is an important skill in RAS. Therefore, the present study aimed to propose a novel objective algorithm based on computer vision that can automatically evaluate a surgeon's clutch use. Additionally, the study aimed to evaluate the correlation between clutch metrics and surgical skill on different surgical robot platforms. The robotic surgery training center of Wuhan University trained 30 laparoscopic surgeons as the study group between 2023 and 2024. Laparoscopic surgeons were trained by combining robotic simulator exercises and RAS animal experiments. During the training, video and hand movement data were collected. Hand movements identified by a skin-color model were combined with labeling information to classify clutch use. The metrics were validated on different robotic platforms (dv-Trainer, EDGE MP1000, Toumai™ MT1000, and DaVinci Xi system) and among surgeons with different surgical skill levels. On the robotic simulator, clutch accuracy in the expert group was significantly higher than in the study group for all tasks. No significant differences were observed in the number of clutches between the expert and study groups. In the RAS experiment, the number of clutches decreased significantly for both study and expert groups. The accuracy was maintained at a high level in the expert group but decreased rapidly in the study group. We proposed a new objective assessment of surgical skills, clutch use metrics, in cross-platform RAS. Additionally, we verified that the metrics significantly correlated with the surgical skill levels of the surgeons.

Optimal Torque Control of the Launching Process with AMT Clutch for Heavy-Duty Vehicles

When launching a heavy-duty vehicle, torque and position control during automatic clutch engagement is critical, and the driver’s intention to launch and changes in the vehicle’s launching resistance make clutch control more complex. This paper analyses the automatic engagement process of automated mechanical transmission (AMT) clutches and proposes an optimal control of the clutch torque for launching heavy-duty vehicles. Firstly, a fuzzy neural network (FNN)-based vehicle launching states recognition (LSR) system is designed for distinguishing the driver’s launching intention and the vehicle’s launching equivalent moment of resistance. Secondly, jerk, friction work, and launching reserve power are taken as the performance indexes for clutch torque optimization, the weight coefficients of each performance index are adjusted according to the LSR results, and the optimal clutch torque is solved by using the minimum value principle based on the shooting method. Finally, simulations and tests are conducted to validate the strategy of optimizing clutch torque, and the impact of torque optimization on the position change during the engagement process is analyzed. The results indicate that under different driver’s intentions, vehicle masses, and road gradient conditions, the jerk, friction work, and slipping time of heavy vehicles during the launching process are improved by applying the optimization strategy.

Design and Optimization of Power Shift Tractor Starting Control Strategy Based on PSO-ELM Algorithm

Power shift tractors have been widely used in agricultural tractors in recent years because of their advantages of uninterrupted power during shifting, high transmission efficiency and high stability. As one of the indispensable driving states of the power shift tractor, the starting process requires a small impact and a starting speed that meets the driver’s requirements. In this paper, aiming at such contradictory requirements, the starting control strategy of a power shift tractor is formulated with the goal of starting quality and the driver’s intention. Firstly, the identification characteristics of the driver under three starting intentions are obtained by a real vehicle test. An extreme learning machine with fast identification speed and short training time is used to establish the basic driver’s intention identification model. For the instability of the identification results of the Extreme Learning Machine (ELM), the particle swarm optimization algorithm (PSO) is used to optimize the ELM. The optimized extreme learning machine model has an accuracy of 96.891% for driver’s intention identification. The wet clutch is an important part of the power shift gearbox. In this paper, the starting control strategy knowledge base of the starting clutch is established by a combination of bench tests and simulation tests. Through the fuzzy algorithm, the driver’s intention is combined with the starting control strategy. Different drivers’ intentions will affect the comprehensive evaluation model of the clutch (the single evaluation index of the clutch is: the maximum sliding power, the sliding power, the speed stability time, the impact degree), thus affecting the final choice of the starting clutch control strategy considering the driver’s intention. On this basis, this paper studies and establishes the MPC starting controller for the power shift gearbox. Compared with the linear control strategy, the PSO-ELM-fuzzy weight starting strategy proposed in this paper can reduce the maximum sliding friction power by 45%, the sliding friction power by 69.45%, and the speed stabilization time by 0.11 s. The effectiveness of the starting control strategy considering the driver’s intention proposed in this paper to improve the starting quality of the power shift tractor is verified.

Online adaptive identification of clutch torque transmissibility for the drivability consistency of high-performance production vehicles

Drivability in vehicles with a wet-type dual-clutch transmission (DCT) relies heavily on the precise torque transfer control of the clutch to efficiently distribute the engine torque to the wheels. However, the large variation in the clutch torque transmissibility caused by temperature and wear and the lack of torque sensors for the driveline in production vehicles are the two significant challenges that hinder accurate clutch control in wet DCT vehicles. Therefore, knowledge regarding clutch torque transmissibility is crucial for realizing the demanded clutch torque because it can help determine the required clutch pressure. Thus, in this study, an online adaptive identification algorithm for clutch torque characteristics is developed for high-performance vehicles with wet-type DCTs. The proposed algorithm estimates each clutch torque characteristic using the extended Kalman filter (EKF) based on a parameterizable model for the torque transmissibility curve, making it applicable to production vehicles. Further, the algorithm incorporates an adaptation law based on the Lyapunov stability theorem to compensate for uncertainties in the engine torque, thereby ensuring a robust identification performance regardless of the installed engine type. The estimation performance and effectiveness of the adaptive identification algorithm are experimentally validated using test vehicles with wet DCT.

Study on Shifting Performance of Tractor Multi-Clutch under Different Engagement Rules

When shifting gears around a tractor’s power shift transmission, it is necessary to coordinate the control of multiple clutches and formulate a reasonable clutch engagement law to ensure the reliability and power of the power system. This paper explores the impact of different clutch engagement patterns on shifting characteristics in a power-shift tractor with multiple clutches. Shifting performance is comprehensively evaluated using indicators such as shifting time, impact degree, slip energies, and transmission output torque. The aim is to enhance the quality of power shifting, operational efficiency, and the service life of the transmission system. This paper takes the YTO TX4A transmission system as the research object, analyzes its working principle, and establishes a mathematical model of a power shift transmission system under different clutch engagement rules. This model of power shift transmission is established based on Matlab2021/Simulink and the AMESim2021 software platform. A simulation analysis is carried out for four clutches working simultaneously in a tractor’s advance gear II and lift gear III. The simulation results indicate that switching rule C is superior to switching rule A and switching rule B. Compared with the engagement scheme in which the torque exchange overlap time for both sets of clutches is 0.3 s, the scheme with a torque exchange overlap time of 0.15 s indicated a shifting time increase of 0.2 s, a slip energy increase of 4%, and a minimum output torque of the transmission increase of 2%. In the scheme with a torque exchange overlap time of 0 s, the shifting time increased by 0.15 s, the slip energy decreased by 13.5%, and the minimum output torque of the transmission decreased by 17%. Through the study of shifting performance under three different clutch engagement patterns, it is concluded that, during the shift from forward gear II to gear III in the YTO TX4A transmission system, appropriately reducing the torque exchange overlap time for both sets of clutches and avoiding simultaneous torque exchange can reduce the complexity of clutch control. This leads to smoother, more powerful, and more comfortable power shifting, effectively prolonging the service life of the transmission system.

Dynamic Characteristics of an Automotive Air-Conditioning Electromagnetic Clutch

The automotive air conditioning (AC) electromagnetic clutch plays a crucial role in accurately controlling power transmission between the engine and the compressor, ensuring the proper operation of the AC system. The aim of this paper is to provide high-quality experimental data for researchers who are interested in simulating the dynamic process of an AC electromagnetic clutch and also to assess the adaptiveness of empirical equations to describe the AC electromagnetic clutch performance that is limited in discussion in existing studies. In this study, an automotive AC electromagnetic clutch characteristic test system was employed along with an infrared (IR) camera to conduct comprehensive experimental analyses. The test system enabled the evaluation of various parameters, including the clutch torque output, compressor exhaust pressure, and temperature of the friction surface. The results revealed that the torque and exhaust pressure were closely associated with the on/off time and rotational speed, with a peak value observed around 3000 rpm. Additionally, longer break-in time, higher rotational speeds, and shorter on/off time led to varying increases in the temperature of the friction surface. These findings provided a theoretical foundation for optimizing the design and control of automotive AC electromagnetic clutches. By enhancing design or adjusting control strategies, these clutches can better handle high-load and high-frequency working conditions.

Fuzzy proportional integral differential control of magnetorheological clutch torque based on bee colony algorithm optimization

As an intelligent transmission device, the magnetorheological (MR) clutch cannot realize its accurate torque control because it is difficult to establish its accurate torque control mathematical model. This paper designs a squeeze shear MR clutch. In order to achieve accurate torque control of the MR clutch, this paper proposes a fuzzy proportional integral differential (PID) control strategy based on the optimization of the bee colony algorithm. Based on the mechanical transmission experiment platform of the MR clutch, the performance of the torque control of the MR clutch is experimentally studied by using the real-time operating system Phar Lap ETS built by LabVIEW real-time module, it is found that the fuzzy PID control strategy based on bee colony algorithm can not only improve the torque control accuracy of the MR clutch by 70% compared to traditional PID control strategies but also increase the response speed by more than 50%.

Development and evaluation of a magnetorheological fluid-based clutch with hybrid excitation

This article presents the development and control of a hybrid excitation magnetorheological (MR) fluid clutch with improved magnetic cores. The clutch adopts a hybrid excitation design with coils and permanent magnets. To obtain an increased torque, an improved magnetic core shape of the permanent magnet is adopted in the clutch. Furthermore, simulation is used to test the magnetic field in the fluid gaps. Then, a prototype is manufactured, and a test bed is built. Experiments prove that the designed hybrid excitation MR clutch has an improved torque. In order to achieve accurate torque output, a genetic algorithm (GA) optimized fuzzy proportional-integral-differential (PID) controller is presented and compared with the other two controllers, and the effectiveness is verified by simulations and experiments. It turns out that the proposed GA optimized fuzzy PID controller is effective in improving the torque tracking accuracy and can be used for torque control of MR clutches.

Driveline oscillation attenuation through Clutch Micro-Slip and Model Predictive Control

This paper considers a Model Predictive Control (MPC) approach to micro-slip clutch control for driveline shuffle attenuation and longitudinal acceleration oscillation reduction in vehicles with an Automated Manual Transmission system. We introduce an original MPC formulation to consider the performance tradeoff between the clutch slip regulation, the torsional oscillation attenuation and the jerking reduction. A particular problem to be considered is handling saturation constraints on the transmitted torque. We employ a piecewise-affine linear model of the actuator-driveline system to take care of special manoeuvres that cause inversions in the transmission motion. On the methodological side, we present a switching MPC approach where the underlying optimization problem is a quadratic programme for a fast online controller implementation on real-world transmission control unit platforms. To show the effectiveness of the proposed approach, we present extensive simulation results and experimental tests performed on a prototype vehicle.

Research on wear law of friction plate of AMT dry clutch under continuous slip wear condition

In the process of operation, because the AMT dry clutch in the process of separation and combination of the slip wear stage, this stage will cause the clutch friction plate wear, resulting in the change of the clutch power transmission performance, but also lead to the change of the clutch engagement characteristics and affect the clutch control performance. Therefore, the purpose of this paper is to study the wear law of the friction plate of the AMT dry clutch, and it is of great significance to evaluate the change in clutch transmission performance and realize the precise control of the clutch. In this paper, the ANSYS analysis software system is used to build a finite element analysis model about the wear of the friction plate of the AMT dry clutch, and a simulation of the sliding wear condition. At the same time, the method of loading heat flux is used to simulate the temperature of the sliding wear condition. The thermal deformation caused by temperature is taken as the main influence factor. To carry on the wear simulation analysis of the clutch-driven disc friction plate. Finally, the wear law of the friction plate of the AMT dry clutch is obtained.

Pressure sensor fault-tolerant control for the filling phase of wet clutches

The filling pressure control is one of the key technologies of wet clutches. Pressure sensor is a key component to realize the closed-loop control of the filling pressure. However, with the working hours increasing, the pressure sensor is prone to be faulty. To ensure the filling performance of wet clutches, this article investigates a pressure sensor fault diagnosis and fault-tolerant control strategy for the filling phase of wet clutches. First, the dynamic model of a hydraulic clutch control system is established where the clutch pressure sensor fault is considered. Second, the optimal filling pressure reference trajectory is constructed by Pontryagin’s minimum principle. In the fault-free case, a feedback controller is designed to track the desire pressure trajectory with an observer estimating the unmeasurable state of the system. Third, an adaptive observer is constructed to estimate the pressure sensor fault. Based on the estimated sensor fault information, a pressure sensor fault-tolerant control strategy is proposed for the filling phase of wet clutches. Simulation results show that the proposed fault-tolerant controller can realize smooth and precise clutch-filling control with pressure sensor fault.

Modeling and Experimental Characterization of a Clutch Control Strategy Using a Magnetorheological Fluid

In this paper, the characterization of a new clutch control strategy by means of a magnetorheological fluid (MR) has been investigated. The clutch system was designed and manufactured in the laboratory in order to determine its static and dynamic characteristics. As a result of experimental measurements, the torque control of the developed MR clutch was determined in the frequency and time domains, as were the analytical relationships describing the connection between the control and controlled variables. The obtained results demonstrate that the analytical models are in good agreement with the experimental data, with an overall error of about 7%.

Research on clutch position control based on backstepping method for small-sized tractors.

Tractors installed automated manual transmission can avoid discomfort for the drivers because of excessive limbs intervention as well as improve shift quality. Automatic clutch control is critical for the performance of the automated manual transmissions. For a good operation, precise and fast control of clutch position is mandatory. In order to meet these requirements, an enhanced strategy focused on the clutch is presented adopting a simple tracking control method based on the detailed models in this study. Clutch models including DC motor model and mechanical actuator model are established and transformed to a controllable model. On the basis of the control model, a clutch position tracking control scheme is proposed composed of motor control circuit and motor angle tracking controller designed according to the backstepping method. Simulations are carried out in comparation with the internal model control method, and the results demonstrate the effectiveness of the presented control scheme by superior rapidity and accuracy of the controller response for the clutch position tracking system.

Static Model-Based Optimization and Multi-Input Optimal Control of Automatic Transmission Upshift during Inertia Phase

Step-ratio automatic transmission upshift performance can be improved by modulating the off-going (OFG) clutch during the inertia phase. In this paper, a static powertrain performance model is derived and applied for the purpose of numerically efficient, multi-objective shift control parameter optimization for the inertia phase. The optimization is aimed at finding the optimal node parameters for simplified, piecewise linear, open-loop profiles of oncoming (ONC) clutch, OFG clutch, and engine torque reduction control variables. The performance indices, i.e., the optimization objectives, include shift comfort, clutch thermal loss, and shift time. The optimization results in 3D Pareto optimal frontiers, which are then analyzed and compared with those obtained by using the previously developed, nonlinear model-based, genetic algorithm optimization tool. The derived method is employed in order to develop a static model-based predictive control (S-MPC) strategy, which commands ONC clutch torque control input while retaining open-loop controls for engine and OFG clutch control inputs. The S-MPC strategy aims at providing the prespecified shift time, while the shift time accuracy is relaxed to some extent by using a control input dead zone element to avoid chattering effect. The S-MPC system performance is verified through simulation and compared with the genetic algorithm benchmark. The simulation results demonstrate that the S-MPC strategy approaches the benchmark performance.

Synthesis of the Energy-Saving Dry Dual Clutch Control Mechanism

A promising direction in developing up-to-date transport vehicles is the use of transmissions, an essential element of which is a dual-clutch. Improving functional performance, energy efficiency, and environmental friendliness are relevant and require appropriate research. The object of study is a dry dual-clutch working with a manual transmission with high energy efficiency. In the proposed design scheme, a rotary lever and a movable carriage can change the structural diagram of the force interaction between the pressure spring and the clutch discs. The developed mathematical model of the clutches control mechanism allowed for analyzing the process of controlling the dual-clutch transmissions (DCT) and obtaining functional dependencies between pushing forces in friction pairs and the carriage position. As a result, a method for synthesizing DCT was proposed to ensure the transmission of a given torque. Furthermore, it was determined and numerically proven that the same radial movement of the carriage when switching-on the clutches does not guarantee equal loading for the frictional discs of each clutch. This fact increases the uneven dynamics of torque and disc wear. Overall, the synthesis of the energy-saving dry dual-clutch control mechanism providing the same clutch margin for each clutch was developed. The method can be generalized and applied to designing dry dual-clutch transmissions for machines of various purposes.

Research on transfer case clutch accurate position control of on-demand four-wheel drive systems

<p indent="0mm">The on-demand four-wheel-drive system has been widely used because of its simple structure and low cost. The core component of the on-demand four-wheel-drive system in this study is a transfer case based on an electronically controlled multi-plate wet clutch. Its actuator consists of a worm gear driven by a permanent magnet synchronous motor and a helical booster mechanism. The actuator can control the position of the clutch pressure plate to change the drive torque transmitted to the front axle, and adjusting the front axle torque significantly affects the handling stability and dynamics. Therefore, the precise position control of the transfer clutch is of great significance. In this paper, a model of the PMSM actuator system and load is first established, which provides the basis for the design of the controller. Then, explicit model predictive controllers for current tracking control and position tracking control are designed based on the model. Finally, typical working condition position tracking simulations and experiments are carried out. The results show that the proposed position control algorithm can achieve relative accuracy of 1%, which can meet the requirements of the real-time online high-precision position control of an on-demand four-wheel-drive system.

ВИКОРИСТАННЯ КІБЕРФІЗИЧНИХ СИСТЕМ ДЛЯ ДОСЛІДЖЕННЯ АГРЕГАТІВ АВТОМОБІЛЯ

Research of control systems of vehicle transmission units is an important stage in the process of creating the latest developments in this area. One of the problems on the way to create and adapt to specific operating conditions of control systems of transmission units is an experimental studies of their operation, including as part of the vehicle. The main difficulty in conducting experimental research is often the high cost of the necessary equipment and the problems associated with the reproduction on a particular experimental stand of various operating conditions of the system. One of the solutions to this problem is the use of cyberphysical systems to test vehicle units and study their control systems. The purpose of the work is theoretical substantiation and practical creation of cyberphysical system, which allows to work out algorithms of control of transmission element in different operating conditions without need of its installation on real vehicle and consists of electropneumatic clutch control mechanism realized at physical level and model of vehicle transmission elements. The approaches adopted in the work to achieve this goal are based on the laws of physics, the main processes and phenomena reproduce and study by mathematical modeling. The research technique which allows to combine experimental methods with receptions of mathematical modeling is offered. The concept of cyberphysical modeling of complex devices and their control systems is presented. The process of transition from the physical to the model level of the cyberphysical system is described, the software and hardware means for its realization are offered. The study of the created cyberphysical system and the comparison of the obtained results with the experimental data of the study of the electropneumatic clutch control drive allowed to draw a conclusion about the possibility of using the proposed approach to test vehicle units. The proposed approaches and the given material and technical base can be used in the design of new and research of previously created units and systems of vehicles. Keywords: cyberphysical model, pneumatic cylinder, DC motor, Arduino, solenoid valve, angle of rotation.

Clutch Control: Changing the Speed and Direction of CAR-T Cell Therapy

Clutch Control: Changing the Speed and Direction of CAR-T Cell Therapy

Design analysis and performance evaluation of a self-locking hydrostatic differential for automated agriculture spray vehicle

The differential is an important part of the automobile transaxle. The purpose of the differential is to distribute power to the two rear wheels and provide differential speed to the vehicle wheels when the vehicle takes a turn. Conventional transaxle of the automobile has clutch, gear box and differential in the power train which makes the transaxle very heavy and also automatic control of the system is difficult, as one has to control the clutch and brake arrangement simultaneously. Single plate clutch is commonly used as the transmission element in most transmissions for four wheeler vehicles. Agriculture vehicles and farming equipment like tractors and Tillers, Sprayers etc., also use a similar automobile transmission. With the shortage in labour and also increase in labour expenses there is a trend to automate the farming equipment to save time and labour cost. The major challenges in automation is the clutch control which is presently manual, and the automatic clutch control in the high end vehicles cannot be used due to the high cost, complexity of design. Hence in order to carry out the automatic control of vehicle an automatic speed control, differential control and brake control is needed. The project work aims at design and development of hydrostatic transmission differential locking system for an automated agriculture vehicle where in the differential drive and control arrangement will be both hydraulically operated. The components will be designed using Unigraphix software and the numerical analysis of the components will be done using Ansys work bench. Further the developed hydrostatic differential lock model will be tested to determine the performance characteristics of the drive.