# Synthesis of the Energy-Saving Dry Dual Clutch Control Mechanism
###### Abstract  
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. robotic transmission; transport vehicle; dual-clutch transmission; torque; clutch margin; process innovation; energy efficiency +
Footnote †: journal: Applied Sciences  
energy consumption when changing switches and maintaining the frictional pairs of one of the the clutches in the closed position. In DCT, opening one clutch and closing the second one occurred in a reduced or overlapped time. Thus, gear shifting is ensured with no interruption in power flow. This significantly reduces gearshift time, improves acceleration dynamics, and reduces fuel consumption and emissions to the environment. One of the ways to improve such clutches is to reduce the energy consumption for control while ensuring reliable transmission of the required torque and safety indicators. Studies of the energy-saving dry clutch control mechanism allow recommending rational choice and a unification of the designs while ensuring the proper functioning of the drive and control system. Recently, significant progress has been reached in the development of transmissions. Particularly, the number of speeds has been increased, the range of gear ratios has been extended, and the gearshift rate has been raised [1]. Electric drives are permanently expanding in response to tightening emission control regulations and urgent fuel economy requirements in automotive transmissions. As a result, integrating electric drives [2] into conventional transmissions occurs. Such an approach simplifies modular designs and the production of transmissions. However, it does not solve the problems of developing and improving the mechanical parts of transmissions. Improving transmissions involves researching dry clutches related to vehicle dynamics [3; 4; 5; 6; 7; 8; 9], reliability [10], clutch architecture [5], durability, noise, switching strategy, and control technology, as well as energy efficiency and comfort [11]. The importance of dry clutch control was previously discussed in refs. [12; 13; 14]. Based on the models of workflows in dry clutches, several control algorithms have been proposed: optimal control [15], branched control [16], adaptive control [17], control based on fuzzy logic [8], robust control [18], combined management strategy [19], and predictive control [5]. Notably, effective clutch control requires developing a mathematical model for torque transmission with a minimum deviation from the actual process [20; 21; 22; 23]. In ref. [4], a detailed analysis of the dry clutch architecture was carried out, allowing one to understand the main phenomena affecting torque transmission by friction forces.