doc. Ing. Kateřina Hyniová, CSc.

Article

Department of Digital Design

: Generally, passenger ride comfort can be interpreted as an attenuation of sprung mass acceleration or as peak minimization of sprung mass vertical displacement, while good handling can be characterized as an attenuation of unsprung mass acceleration. This effort devoted to passive suspension design is ineffective because improvements to ride comfort are achieved at the expense of handling and vice versa. Instead, the best result can be achieved by active suspension, i.e. when an additional force can act on the system and simultaneously improve both of these conflicting requirements. Another important goal of the control design is to maintain robustness of the closed loop system. In the paper, fuzzy logic is used to simulate active suspension control of a one-half-car model. Velocity and acceleration of the front and rear wheels and undercarriage velocity above the wheels are taken as input data of the fuzzy logic controller. Active forces improving vehicle driving, ride comfort, and handling properties are considered to be the controlled actuator outputs. The controller design is proposed to minimize chassis and wheels deflection when uneven road surfaces, pavement points, etc. are acting on tires of running cars. As a result, a comparison of an active suspension fuzzy control and a spring/damper passive suspension is shown using MATLAB simulations.

Proceedings paper

Department of Digital Design

: Generally, passenger ride comfort can be interpreted as attenuation of sprung mass acceleration or as peak minimization of sprung mass vertical displacement, while good handling can be characterized as attenuation of unsprung mass acceleration. This effort devoted to passive suspension design is ineffective because improvements to ride comfort are achieved at the expense of handling and vice versa. Instead, the best result can be achieved by active suspension, i.e. when an additional force can act on the system and simultaneously improve both of these conflicting requirements. Another important goal of the control design is to maintain the robustness of the closed-loop system. In the paper, fuzzy logic is used to simulate active suspension control of a one-half-car model. Velocity and acceleration of the front and rear wheels and undercarriage velocity above the wheels are taken as input data of the fuzzy logic controller. Active forces improving vehicle driving, ride comfort, and handling properties are considered to be the controlled actuator outputs. The controller design is proposed to minimize chassis and wheel deflection when uneven road surfaces, pavement points, etc. are acting on the tires of running cars. As a result, a comparison of an active suspension fuzzy control and a spring/damper passive suspension is shown using MATLAB simulations.

Article

Department of Digital Design

The paper deals with innovations in vehicle suspension technology developed in Josef Bozek´s Research Center of Combustion Engines and Automobiles at CTU in Prague, Czech Republic. A unique innovative suspension system that uses a linear electric motor as a controlled actuator has been designed. Many experiments on energy management in the system have been accomplished. In order to verify various control strategies and to test different ways of energy consumption optimization we designed and constructed a unique one-quarter-car test stand. To realize simulation and practical experiments at the test stand it is necessary to find a proper experimental road disturbance signal to excite the active suspension system. The disturbance signal is applied on one more linear motor that is placed under a wheel of the one-quarter-car test stand to excite the active suspension system. The paper deals with the way and results of experimental verification of vehicle active suspension behavior when robust control is applied and also with the energy management strategy that is used in the system. A modified H-infinity controller that enables to set energy management strategy is mentioned in the paper. At the close of the paper, some experiments taken on the one quarter-car model and their evaluation are discussed.

Proceedings paper

Department of Digital Design

In the paper, energy recuperation and management in automotive suspension systems with linear electric motors controlled using a proposed H∞ controller to obtain a variable mechanical force for a car damper is presented. Vehicle suspensions in which forces are generated in response to feedback signals by active elements obviously offer increased design flexibility compared to the conventional suspensions using passive elements such as springs and dampers. The main advantage of the proposed solution using a linear AC motor is the possibility to generate desired forces acting between the unsprung and sprung masses of the car, providing good insulation of the car sprung mass from the road surface disturbances. In addition, under certain circumstances using linear motors as actuators enables to transform mechanical energy of the vertical car vibrations to electrical energy, accumulate it, and use it when needed. Energy flow control (management) enables to reduce or even eliminate the demands concerning the external power source.

Proceedings paper

Department of Digital Design

In the paper, the design of a linear motor as an actuator in-vehicle active suspension systems will be presented. The attention is focused on several interesting design aspects of a non-traditional actuator (a linear synchronous permanent magnet motor with electronic commutation) controlled to obtain a variable mechanical force for a car active suspension. The main advantage of such a solution is the possibility to generate desired forces acting between the unsprung (wheel) and sprung (car body) masses of the car, providing good insulation of the car sprung mass from the road surface disturbances. In addition, under certain circumstances, it is possible to reduce or even eliminate the demands concerning the external power source.

Article

Department of Digital Design

In the paper, the design of a linear motor as an actuator in-vehicle active suspension systems will be presented. The attention is focused on several interesting design aspects of a non-traditional actuator (a linear synchronous permanent magnet motor with electronic commutation) controlled to obtain a variable mechanical force for a car active suspension. The main advantage of such a solution is the possibility to generate desired forces acting between the unsprung (wheel) and sprung (car body) masses of the car, providing good insulation of the car sprung mass from the road surface disturbances. In addition, under certain circumstances, it is possible to reduce or even eliminate the demands concerning the external power source.

Proceedings paper

Department of Digital Design

: In the paper, energy recuperation and management in automotive suspension systems with linear electric motors controlled using a proposed H∞ controller to obtain a variable mechanical force for a car damper is presented. Vehicle suspensions in which forces are generated in response to feedback signals by active elements obviously offer increased design flexibility compared to the conventional suspensions using passive elements such as springs and dampers. The main advantage of the proposed solution using a linear AC motor is the possibility to generate desired forces acting between the unsprung and sprung masses of the car, providing good insulation of the car sprung mass from the road surface disturbances. In addition, under certain circumstances using linear motors as actuators enables to transform mechanical energy of the vertical car vibrations to electrical energy, accumulate it, and use it when needed. Energy flow control (management) enables to reduce or even eliminate the demands concerning the external power source.

Article

Department of Digital Design

In the paper, energy recuperation and management in automotive suspension systems with linear electric motors controlled using a proposed H∞ controller to obtain a variable mechanical force for a car damper is presented. Vehicle suspensions in which forces are generated in response to feedback signals by active elements obviously offer increased design flexibility compared to the conventional suspensions using passive elements such as springs and dampers. The main advantage of the proposed solution using a linear AC motor is the possibility to generate desired forces acting between the unsprung and sprung masses of the car, providing good insulation of the car sprung mass from the road surface disturbances. In addition, under certain circumstances using linear motors as actuators enables to transform mechanical energy of the vertical car vibrations to electrical energy, accumulate it, and use it when needed. Energy flow control (management) enables to reduce or even eliminate the demands concerning the external power source.

Proceedings paper

Department of Digital Design

: It is often assumed that if practical difficulties are neglected, active systems could produce in principle arbitrary ideal behavior. This paper presents the factorization approach that is taken to derive limitations of achievable frequency responses for active vehicle suspension systems in terms of invariant frequency points and restricted rate of decay at high frequencies. The factorization approach enables us to determine complete sets of such constraints on various transfer functions from the load and road disturbance inputs for typical choices of measured outputs and then choose the “most advantageous” vector of the measurements from the point of view of the widest class of the achievable frequency responses. Using a simple linear two degree-of-freedom car suspension system model it will be shown that even using complete state feedback and in the case of in which the system is controllable in the control theory sense, there still are limitations to suspension performance in the fully active state.

Article

Department of Digital Design

It is often assumed that if practical difficulties are neglected, active systems could produce in principle arbitrary ideal behavior. This paper presents the factorization approach that is taken to derive limitations of achievable frequency responses for active vehicle suspension systems in terms of invariant frequency points and restricted rate of decay at high frequencies. The factorization approach enables us to determine complete sets of such constraints on various transfer functions from the load and road disturbance inputs for typical choices of measured outputs and then choose the “most advantageous” vector of the measurements from the point of view of the widest class of the achievable frequency responses. Using a simple linear two degree-of-freedom car suspension system model it will be shown that even using complete state feedback and in the case of in which the system is controllable in the control theory sense, there still are limitations to suspension performance in the fully active state.

Invited/Awarded proceedings paper

Department of Digital Design

— In the paper, energy recuperation and energy flow distribution in automotive suspension systems with linear electric motors controlled using a proposed H∞ controller to obtain a variable mechanical force for a car damper is presented. Vehicle suspensions in which forces are generated in response to feedback signals by active elements obviously offer increased design flexibility compared to the conventional suspensions using passive elements such as springs and dampers. The main advantage of the proposed new solution using a linear AC motor is the possibility to generate desired forces acting between the unsprung and sprung masses of the car, providing good insulation of the car sprung mass from the road surface disturbances. In addition, under certain circumstances using linear motors as actuators enables to transform mechanical energy of the vertical car vibrations to electrical energy, accumulate it, and use it when needed. Energy flow control enables to reduce or even eliminate the demands concerning the external power source.

Article

Department of Digital Design

In the paper, energy recuperation and energy flow distribution in automotive suspension systems with linear electric motors controlled using a designed H∞ controller to obtain a variable mechanical force for a car active damper is presented. Vehicle suspensions in which forces are generated in response to feedback signals by active elements obviously offer increased design flexibility compared to the conventional suspensions using passive elements such as springs and dampers. The main advantage of the specified new solution using a linear AC motor is the possibility to generate desired forces acting between the unsprung and sprung masses of the car, providing good insulation of the car sprung mass from the road surface and load disturbances. In addition, under certain circumstances, the application of linear motors as actuators enables to transform mechanical energy of the vertical car vibrations to electrical energy, accumulate it, and use it when needed. Energy flow control enables to reduce or even eliminate the demands concerning the external power source.

Article

Department of Digital Design

The paper deals with a variable multifunctional simulation tool that enables to design and assemble animated models of various technological processes controlled by externally connected fuzzy logic unit. It enables to verify the correctness of fuzzy controller settings in the future control of real technological processes in practice. This tool represents an effective, innovative, and creative concept important to understanding control approach of technological processes modelling as an insight to behaviour of real industrial processes and their control which is based on fuzzy logic. On the base of this animated simulation, real technological processes control can be realized successfully according to producer demands afterwards. Models of technological processes assembled by this simulation tool can be then externally controlled by various control strategies (traditional PID controllers, ON-OFF controllers, PLC controllers, fuzzy logic controllers etc.) via a proper real controller connected to the computer. In the paper, two-conveyor-belt system for product packing is shown. The goal consists in control of synchronization of products and boxes placed on individual conveyor belts in order to pack the product into the box. The main concern here is to improve dynamic performance and control efficiency with the help of assembling an animated model of the controlled technological process and its external control by a fuzzy logic unit.

Proceedings paper

Department of Digital Design

The paper deals with a variable multifunctional simulation tool that enables to design and assemble animated models of various technological processes controlled by externally connected fuzzy logic unit. It enables to verify the correctness of fuzzy controller settings in the future control of real technological processes in practice. This work represents an effective, innovative, and creative concept important to understanding control approach of technological processes modelling as an insight to behaviour of real industrial processes and their control which is based on fuzzy logic. On the base of this animated simulation, real technological processes control can be realized successfully according to producer demands afterwards.

Proceedings paper

Department of Digital Design

: In the paper, fuzzy logic is used to simulate active suspension control of a one-half-car model. Velocity and acceleration of the front and rear wheels and undercarriage velocity above the wheels are taken as input data of the fuzzy logic controller. Active forces improving vehicle driving, ride comfort and handling properties are considered to be the controller outputs. The controller design is proposed to minimize chassis and wheels deflection (sky-hook concept) when uneven road surfaces, pavement points, etc. are acting on tires of the running car. As a result, a comparison of an active suspension fuzzy control and a spring/damper passive suspension is shown using MATLAB simulations.

Article

Department of Digital Design

In the paper, fuzzy logic is used to simulate active suspension control of a one-half-car model. Velocity and acceleration of the front and rear wheels and undercarriage velocity above the wheels are taken as input data of the fuzzy logic controller. Active forces improving vehicle driving, ride comfort and handling properties are considered to be the controller outputs. The controller design is proposed to minimize chassis and wheels deflection (sky-hook concept) when uneven road surfaces, pavement points, etc. are acting on tires of the running car. As a result, a comparison of an active suspension fuzzy control and a spring/damper passive suspension is shown using MATLAB simulations.

Article

Department of Digital Design

Generally, passenger ride comfort can be interpreted as an attenuation of sprung mass acceleration or as peak minimization of sprung mass vertical displacement, while good handling can be characterized as an attenuation of unsprung mass acceleration. This effort devoted to passive suspension design is ineffective because improvements to ride comfort are achieved at the expense of handling and vice versa. Instead, the best result can be achieved by active suspension, i.e. when an additional force can act on the system and simultaneously improve both of these conflicting requirements. Another important goal of the control design is to maintain robustness of the closed loop system. In the paper, fuzzy logic is used to simulate active suspension control of a one-half-car model.

Proceedings paper

Department of Digital Design

The paper deals with a variable multifunctional simulation tool that enables to design and assemble animated models of various technological processes controlled by externally connected fuzzy logic unit. It enables to verify the correctness of fuzzy controller settings in the future control of real technological processes in practice. This work represents an effective, innovative, and creative concept important to understanding control approach of technological processes modelling as an insight to behaviour of real industrial processes and their control which is based on fuzzy logic. On the base of this animated simulation, real technological processes control can be realized successfully according to producer demands afterwards. Models of technological processes assembled by this simulation tool can be then externally controlled by various control strategies (traditional PID controllers, PLC controllers, fuzzy logic controllers etc.) via a proper controller connected to the computer. In the paper, two-conveyor-belt system for product packing is shown. The goal consists in control of synchronization of products and boxes placed on individual conveyor belts in order to pack the product into the box into. The main concern here is to improve dynamic performance and control efficiency with the help of assembling an animated model of the controlled technological process and its external control by fuzzy logic unit.

Proceedings paper

10.1051/itmconf/20170903003

Department of Digital Design

Suspension system influences both the comfort and safety of the passengers. In the paper, energy recuperation and management in automotive suspension systems with linear electric motors that are controlled by a designed H∞ controller to generate a variable mechanical force for a car damper is presented. Vehicle shock absorbers in which forces are generated in response to feedback signals by active elements obviously offer increased design flexibility compared to the conventional suspensions with passive elements (springs and dampers). The main advantage of the proposed solution that uses a linear AC motor is the possibility to generate desired forces acting between the unsprung (wheel) and sprung (one-quarter of the car body mass) masses of the car, providing good insulation of the car sprung mass from the road surface roughness and load disturbances. As shown in the paper, under certain circumstances linear motors as actuators enable to transform mechanical energy of the vertical car vibrations to electrical energy, accumulate it, and use it when needed. Energy flow control enables to reduce or even eliminate the demands on the external power source. In particular, the paper is focused on experiments with active shock absorber that has been taken on the designed test bed and the way we developed an appropriate input signal for the test bed that as real road disturbance acts upon the vibration absorber and the obtained results are evaluated at the end. Another important point the active suspension design should satisfy is energy supply control that is made via standard controller modification, and which allows changing amount of energy required by the system. Functionality of the designed controller modification was verified taking various experiments on the experiment stand as mentioned in the paper.

Proceedings paper

Department of Digital Design

— Suspension systems influence both the comfort and safety of passengers and protect road surface from damage, too. In the paper, energy recuperation and management in automotive suspension systems with linear electric motors that are controlled by a designed robust H∞ controller to generate a variable mechanical force for a car damper is presented. The robust controller is necessary to design for the suspension system because the vehicle parameters often vary in a wide range. Especially the body mass varies for every single drive. Vehicle shock absorbers in which forces are generated in response to feedback signals by active elements obviously offer increased design flexibility compared to the conventional suspensions with passive elements (springs and dampers). The main advantage of the proposed solution that uses a linear AC motor is the possibility to generate desired forces acting between the unsprung (wheel) and sprung (one-quarter of the car body mass) masses of the car, providing good insulation of the car sprung mass from the road surface roughness and load disturbances. As shown in the paper, under certain circumstances linear motors as actuators enable to transform mechanical energy of the vertical car vibrations to electrical energy, accumulate it, and use it later when needed. Energy consumption and accumulation control enables to reduce or even eliminate the demands on the external power source. In particular, the paper is focused on experiments with active shock absorber that has been taken on a unique verification device we designed and constructed as well as the way we developed an appropriate input signal for the test device that as a real road disturbances act upon the vibration absorber. Obtained results of various experiments are shown and evaluated at the end.

Article

Department of Digital Design

Suspension system is an important part of the car design, because it influences both the comfort and safety of the passengers. In the paper an active suspension using linear electric motor is designed. In particular, the article is focused on experiments with active suspension – developing an appropriate input signal for the test sand and evaluation of the results. Second important point of the active suspension design is energy demands of the suspension system. Modification of the standard controller which allows changing amount of energy required by the system has been designed. Functionality of the modification was verified taking various experiments.

Article

Department of Digital Design

The paper deals with a variable multifunctional simulation tool that enables to design and assemble animated models of various technological processes controlled by externally connected various types of real controllers. It enables to verify the correctness of controller settings in the future control of real technological processes in practice. This work represents an effective, innovative, and creative concept important to understanding control of technological processes mainly in education.

Proceedings paper

Department of Digital Design

The paper deals with a variable multifunctional simulation tool that enables to design and assemble animated models of various technological processes controlled by externally connected various types of real controllers. It enables to verify the correctness of controller settings in the future control of real technological processes in practice. This work represents an effective, innovative, and creative concept important to understanding control of technological processes mainly in education.

Article

Department of Digital Design

The paper deals with a variable multifunctional simulation tool that enables to design and assemble animated models of various technological processes controlled by externally connected various types of real controllers. It enables to verify the correctness of controller settings in the future control of real technological processes in practice. This work represents an effective, innovative, and creative concept important to understanding control of technological processes mainly in education.

Proceedings paper

Department of Digital Design

A laboratory model of the given technological process including PLC control has been designed at CTU in Prague . The model simulates principles of a sorting production line and is designed by means of conveyor belts and sorting sliding transporters. Boxes transported on the conveyor belts are filled up with various subjects and sorted on the base of their color. Control of the model is manual or automatic. Each element in the model is individually controllable as well as velocity of the conveyor belts and movement direction of the sliding transporters.

Article

Department of Digital Design

The research team has designed a unique innovative suspension system that uses a linear electric motor as a controlled actuator. We have undertaken many experiments on energy management in the system. In order to verify various control strategies and to test different ways of energy consumption optimization we designed and constructed a unique one-quarter-car test stand on which we have tested different control strategies In order to realize simulation and practical experiments at the test stand it is necessary to find a proper experimental road disturbance signal to excite the active suspension system The disturbance signal is applied on a one more linear motor that is placed under a wheel of the one-quarter-car model to excite the active suspension system The paper deals with the way and results of experimental verification of vehicle active suspension behavior when robust control is applied and also with energy management strategy that we used in the system.

Proceedings paper

Department of Digital Design

In the paper, fuzzy logic is used to simulate active suspension control of a one -half-car model. Velocity and acceleration of the front and rear wheels and undercarriage velocity above the wheels are taken as input data of the fuzzy logic controller. Active forces improving vehicle driving, ride comfort and handling properties are considered to be the controller outputs. The controller design is proposed to minimize chassis and wheels deflection when uneven road surfaces, pavement points, etc. are acting on tires of running cars. As a result, a comparison of an active suspension fuzzy control and a spring/damper passive suspension is shown using MATLAB simulations.

Proceedings paper

Department of Digital Design

The paper deals with a variable multifunctional simulation tool that enables to design and assemble animated models of various technological processes controlled by externally connected fuzzy logic unit. It enables to verify the correctness of fuzzy controller settingsin the future controlof real technological processes in practice. On the base of this animated simulation , real technological processes controlcan be realized successfullyaccording to the producer demands afterwards.

Proceedings paper

Department of Digital Design

The opportunistic communication networks are special communication networks where no assumption is made on the existence of a complete path between two nodes wishing to communicate; the source and destination nodes needn't be connected to the same network at the same time. This assumption makes the routing in these networks extremely difficult. We proposed the novel opportunistic networking routing algorithm, which improves the basic opportunistic networking routing algorithm by application of machine learning. The HMM Autonomous Robot Mobility Models and Node Reachability Model are constructed from the observed data and used in a proposed routing scheme in order to compute the combined probabilities of message delivery to the destination node. In the proposed routing scheme, the messages are coppied between two nodes only if the combined probability of the message delivery to the destination node is higher than the preliminary defined limit value. The routing scheme was developed for the networks of autonomous mobile robots. The improvement about 70% in a network load is reported.

Invited/Awarded proceedings paper

Department of Digital Design

— Between 2010 and 2014, the research team of Josef Bozek Research Center of Combustion Engines and Automobiles at the Czech Technical University in Prague, Czech Republic, has developed innovations in vehicle suspension technology. The research team has designed a unique innovative suspension system that uses a linear electric motor as a controlled suspension actuator and provides desired forces between wheel and car body. We have undertaken many experiments on energy management in the system. In order to verify various control strategies and to test different ways of energy consumption optimization we designed and constructed a unique one-quarter-car test stand. The paper deals with the way and results of experimental verification of vehicle active suspension behavior when robust control is applied and also with energy management strategy that we used in the system.

Proceedings paper

Department of Digital Design

In this paper, a basic way to fuzzy logic unit utilization on vibration isolation device driver development is briefly described. In this paper, fuzzy logic is used to simulate active suspension of vibrations by linear electric motor on a one-quarter and one-half-car models. Fuzzy approach is one of the frequently used active research and development areas at the present time, particularly in the automobile industry because fuzzy logic can improve vehicle ride comfort and road handling performance. The ride comfort is improved by means of reduction of the body acceleration caused by the car body when road disturbances from uneven road surfaces, pavement points, cargo mass changes, etc. act on the tires of running cars. Velocity and acceleration of the front and rear wheels and undercarriage velocity above the wheels are taken as input data of the fuzzy logic controller. Active forces improving vehicle driving, ride comfort and handling properties are considered to be the controller outputs. The controller design is proposed to minimize chassis and wheels deflection when disturbances are acting on tires of running cars. As a result, a comparison of an active suspension fuzzy control and a spring/damper passive suspension is shown using MATLAB simulations.

Proceedings paper

Department of Digital Design

In this paper, a basic way to fuzzy logic unit utilization on vibration isolation device driver development is briefly described. In this paper, fuzzy logic is used to simulate active suspension of vibrations by linear electric motor on a one-quarter and one-half-car models. Fuzzy approach is one of the frequently used active research and development areas at the present time, particularly in the automobile industry because fuzzy logic can improve vehicle ride comfort and road handling performance. The ride comfort is improved by means of reduction of the body acceleration caused by the car body when road disturbances from uneven road surfaces, pavement points, cargo mass changes, etc. act on the tires of running cars. Velocity and acceleration of the front and rear wheels and undercarriage velocity above the wheels are taken as input data of the fuzzy logic controller. Active forces improving vehicle driving, ride comfort and handling properties are considered to be the controller outputs. The controller design is proposed to minimize chassis and wheels deflection when disturbances are acting on tires of running cars. As a result, a comparison of an active suspension fuzzy control and a spring/damper passive suspension is shown using MATLAB simulations. At the Czech Technical University in Prague various alternative strategies and innovations to classical passive suspension systems improving ride comfort of passengers, providing steering stability, maximizing safety and improving handling properties of vehicles have been researched. In order to improve handling and comfort performance instead of a conventional static spring and damper system, a unique active suspension system has been developed. Certainly there are numerous variations and different configurations of vibration suspension. In this paper, fuzzy logic is used to simulate active linear electric motor suspension of vibrations in a one-quarter and a one-half-car model. It is one of the most active res

Article

Department of Digital Design

Between 2001 and 2012, the Josef Bozek Research Center of Combustion Engines and Automobiles at the Czech Technical University in Prague, Czech Republic, has been developing innovations in suspension technology. The research team has designed a unique suspension system that uses a linear electric motor as a controlled actuator and provides the desired forces between wheel and car body. Many experiments on energy management in the system have also been undertaken. In order to verify various control strategies and to test ways of optimizing energy consumption, a unique one-quarter-car test stand has been designed and constructed.

Article

Department of Digital Design

The main goal of the paper is to describe H∞ controlled active suspension design with respect to the management of the energy flow distribution. In the time of growing interest in the overall minimization of energy consumption, the presented paper could be taken as a contribution to these efforts. Especially in the application field of automotive vehicles, the energy consumption optimization plays an important role in the design process. In the paper, energy recuperation and management in automotive suspension systems with linear electric motors that are controlled by a designed H∞ controller to generate a variable mechanical force for a car damper is presented. Vehicle shock absorbers in which forces are generated in response to feedback signals by active elements obviously offer increased design flexibility compared to the conventional suspensions with passive elements (springs and dampers). In particular, the paper is focused on experiments with active shock absorber that has been taken on the designed test bed and the way we developed an appropriate input signal for the test bed that as real road disturbance acts upon the vibration absorber and the obtained results are evaluated at the end. Another important point the active suspension design should satisfy is energy supply control that is made via standard controller modification, and which allows changing amount of energy required by the system. Functionality of the designed controller modification was verified taking various experiments on the experiment stand as mentioned in the paper.

Proceedings paper

Department of Digital Design

The main goal of the paper is to describe H∞ controlled active suspension design with respect to the management of the energy flow distribution.As shown in the paper, under certain circumstances linear motors as actuators enable to transform mechanical energy of the vertical car vibrations to electrical energy, accumulate it, and use it when needed. Energy flow control enables to reduce or even eliminate the demands on the external power source. In particular, the paper is focused on experiments with active shock absorber that has been taken on the designed test bed .

Proceedings paper

Department of Digital Design

The paper aims to show that there are some frequency points and frequency ranges where the transfer functions have modulus strictly greater than one i.e. where road and load disturbance amplification occurs. On the base of the Bode integral theorems a proof will be given to show that the transfer functions must be greater in modulus to at least the same extend that it is less than one, when measured in terms of the area on a Bode magnitude plot. In such a case there is a possibility to shift frequency ranges where disturbance amplification occurs to a "more advantageous place" or to make magnitudes lower spreading the frequency range.

Article

Department of Digital Design

In the paper, fuzzy logic is used to control active suspension of a one-half-car model. Velocity and acceleration of the front and rear wheels and undercarriage velocity above the mentioned wheels are taken as input data of the fuzzy logic controller. Active forces improving vehicle driving, ride comfort and handling properties are considered to be the controller outputs. The controller design is proposed to minimize chassis and wheels deflection when uneven road surfaces, pavement points, etc. are acting on the tires of running cars. In the conclusion, a comparison of active suspension fuzzy control and spring/damper passive suspension is shown using MATLAB simulations.