Jarosław Mamala

Shift speed control in CVT powertrain

Continuously Variable Transmission (CVT) is associated with a need to solve the problem of the selection of drive train ratio in the vehicle. For the case of a considerable range of the drive train ratio the power delivered to the driven wheels is affected by the mechanical inertia of the rotating mass associated with the crankshaft. The theoretical considerations in this paper as well as the analysis of the results of research clearly indicate the need of accounting for shift speed in the CVT control algorithm.

Automatic Gear Shift Unit

Automatization of gear shift and number selection in passenger cars with stepped transmission result in improvement of driving safety due to concentration of driver’s attention on the conditions of the traffic [1, 3]. Besides, the car can be used by a disabled person. The most important benefit of the projected solution is associated with reduction in fuel consumption resulting from the more economical selection of the transmission ratio [4, 5, 7]. The gear number choice depends on many factors, for example: traffic conditions, temporum vehicle and engine rotational speed as well as engine load. It is very often the case that even a driver with experience can face problems with optimal decisions. Automatically controlled system with suitable algorithm can reduce fuel consumption and improve the vehicle drivability. The system named MeGSS (Mechatronic Gear Shift System) has been developed for this purpose. It was subsequently tested in a passenger car equipped with five-step gear box. In the car the MeGSS is responsible for engine start process and the gear shift procedure. In this system the manual (M) and automatic (A) gear ratio control is possible. The gear shift procedure is connected with electronic throttle control algorithm, which promote smooth power transmission [2, 6].

THE NEW DATA EXCHANGE FACILITIES WITH CAN-FD

The modern vehicles demand more and more data exchange to coordinate, control and monitor functions of on board system. The variety of networks applied in these systems is featured mainly by the bandwidth and time determinism. The development electronic information and network sciences find its reflection in the new and new automotive implementations. The last significant step towards the increase the throughout put of the on board network channels are works on CAN-FD. CAN is now the most common network present on board. It helps to manage the maintenance with the numerous subassemblies of the modern car. Next to the many features making CAN so useful and popular, there is a bandwidth limitation, which slows down further implementation of it. The new CAN-FD specification adds new properties that extend the possibilities of CAN as automotive network protocol. These are: different speed transmission in the arbitration phase and in the data phase during the message transmission as well as the extending the maximum size of data filed of the frame from 8 (CAN) to 64 (CAN-FD). In the paper there have been presented the limitations of existing CAN protocol usage, the explanation of the basics of the arbitration mechanisms and the response of the scientist and engineers to cope with it, as well as the formal result outlined in the CAN-FD

Engine Control Unit Testing by Hardware-in-the-Loop Simulation

The article presents simulator of injection-ignition system of internal combustion engine with spark ignition developed at the Technical University of Opole. This system is based on Bosch series engine ECU with software 7.5. It allows to analyze of motor parameters using both on-board diagnostic system, and data network CAN BUS under different operating conditions of the system. For this purpose, the simulator is equipped with a number of additional devices enable to generate repetitive input signals for the ECU, allowing to open the actual working conditions. Crucial for the simulator was to generate the signals informing ECU about the instantaneous position of the crankshaft and camshaft. For this purpose, the module Arduino was used. This type of solution allows, to recreate momentary engine operating conditions. This article also presents the concept of development with new features and sentences feasible for this type of device and simulation mode.