Search Results

Developments of new Electric and Hybrid propulsion systems demands chassis adaptations. The purpose of the XeV project was to develop and integrate a full suite of active chassis systems to deliver a fully electrified All-Wheel-Drive Pick-up truck. To achieve so, a new chassis frame, engine cradles and battery box were designed to bring direct drive from electric motor to wheel. On the other hand, for a four-wheelindependent-drive, a new rear suspension design was implemented, and a complex torque vectoring and traction control strategy was developed to provide optimum on and off road performance. All systems were tuned to meet the new drivetrain configuration, weight distribution and vehicle loading conditions making it possible to achieve comparable results with respect to the original combustion engine vehicle.

Semi-active suspension systems aim to improve the vehicle safety and comfort. For these systems control laws are required to achieve the desired performance improvements. On the other hand, the instrumentation of the vehicle suspension typically consists only in accelerometers, which are used to measure the vertical accelerations. However, velocities and/or displacements are required to implement the most common control algorithms for semi-active suspension systems. For instance, Skyhook and Groundhook controllers require the knowledge of the suspension vertical velocities. In this article several vertical velocities estimation approaches are studied and compared. In practical applications, it is common to use simple integrators to estimate these variables; nonetheless, it is well known that integrator-based estimations present errors due to drift. In applications where high performance is required, a better estimation of the state variables of the suspension system is essential.

A proposal of fault detection using Linear Parameter Varying (LPV) systems is experimentally validated on embedded systems. The fault detection system is oriented to faulty sensors and / or actuators. The study case is a Quarter of Vehicle (QoV) with suspension using a controllable shock absorber which uses a SkyHook controller. The experimental testbed uses Hardware-in-the-Loop (HiL) to validate the approach. The HiL is an automotive Electronic Control Unit (ECU), and the QoV model is embedded in a Field-Programmable Gate Array (FPGA). Results exhibit the effectiveness of the approach which is consistent with numerical simulation. These results open the application of LPV approaches to commercial vehicles since it is easy of implementation for several features such as, low computation load, lumped parameter model and available for nonlinear dynamic systems.

A comparative analysis between three different semi-active suspension control techniques in a full vehicle model of a pick-up truck is presented. Each independent corner of the vehicle uses a Magneto-Rheological (MR) damper model. The MR damper model includes nonlinearities, hysteresis, and transient response between the manipulation and actuation. The damper model parameters have been obtained from experimental data provided from a BWI™ MR damper. Different tests were used to evaluate the semi-active control strategies by using the CarSim® software. The evaluated controllers, which are based on switching manipulation between the low and high damping force, are: 1) the hybrid controller, 2) Mix 1-sensor (Mix-1) and 3) Frequency Estimation-Based (FEB) controller. These selected controllers share the next features: the use of few sensors, free of models, and they do not require anti-saturation mechanisms.

In this paper a performance analysis of a Networked Control System (NCS) based in Controller Area Network (CAN) is presented. The analysis is done considering three variables of CAN: baud rate, priority of message and network load. These parameters directly affect the network delay and in consequence the feedback control performance. An active suspension model is considered and extensive experimental results have been performed to demonstrate the influence of these parameters in the quality of control performance. An experimental system which includes a pedagogic scale model with real car components was exploited.

This paper deals with the problem of ride and one feasible control strategy solution. Ride in this study is understood as the comfort of the passengers in forward travel in a cruise speed and exposed to road disturbances. This problem is usually addressed with appropriate damping calibration; however for different speeds and road conditions, even a well tuned suspension has limitations. The possibility of semi active solutions is therefore considered and a control strategy with heuristic properties is proposed for heave, pitch and roll motion in a separate fashion. It is the intention of this study to formulate laws separately that can be implemented for future integration.

The industrial communication network field has experienced a great growth throughout the years due to the complexity achieved by the automation systems in several areas (industrial control, automotive, aircrafts, ships, home automation, etc.). An autotronics laboratory for learning automotive communication network CAN (Controller Area Network), automotive electronic and automotive control systems in the context of an industrial collaboration agreement is presented. Several workshops are described in order to illustrate the autotronics educational project based on active learning methods. Results are evaluated based on ABET criteria.