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Benjamin Schwarz - One of the best experts on this subject based on the ideXlab platform.

  • The wheel-individually steerable front axle of the research vehicle “SpeedE” – virtual design and achieved performance of the first prototype
    Proceedings, 2014
    Co-Authors: Benjamin Schwarz
    Abstract:

    The Institute for Automotive Engineering at RWTH Aachen University (ika), is currently developing, constructing, and implementing the research vehicle SpeedE as an open research and innovation platform for research and industry. On research focus of the SpeedE concept, amongst others, is the innovative front suspension. Not only is the front axle’s steer-by-wire system able to steer each wheel individually, but it is also able to achieve steering angles of up to 90°. These requirements lead to an unconventional setup of the axle replacing the tie rod and the rack and pinion steering gear of a double wishbone suspension by two steering actuators consisting of an electric motor and a strain wave reduction gear located at the outer kinematic hardpoint of the upper control arm and mounted to the wishbone through a Cardan Joint.

  • the wheel individually steerable front axle of the research vehicle speede virtual design and achieved performance of the first prototype
    2014
    Co-Authors: Benjamin Schwarz
    Abstract:

    The Institute for Automotive Engineering at RWTH Aachen University (ika), is currently developing, constructing, and implementing the research vehicle SpeedE as an open research and innovation platform for research and industry. On research focus of the SpeedE concept, amongst others, is the innovative front suspension. Not only is the front axle’s steer-by-wire system able to steer each wheel individually, but it is also able to achieve steering angles of up to 90°. These requirements lead to an unconventional setup of the axle replacing the tie rod and the rack and pinion steering gear of a double wishbone suspension by two steering actuators consisting of an electric motor and a strain wave reduction gear located at the outer kinematic hardpoint of the upper control arm and mounted to the wishbone through a Cardan Joint.

Ion Bulac - One of the best experts on this subject based on the ideXlab platform.

Pp Valentini - One of the best experts on this subject based on the ideXlab platform.

  • Effect of elasticity and manufacturing tolerances on the kinematic and dynamic performances of a Cardan Joint
    2015
    Co-Authors: Pennestrì E, Pp Valentini
    Abstract:

    Cardan Joint is a very widely used assembly in many mechanical fields [1]. It is comprised of an input and output shafts with two forks and a cross. Each fork hole is connected to a cross pin by means of a revolute Joint. In transmission simulations, it is often included using a “black box” approach, by adding coupling relationships between the relative velocities of the connected shafts. On the other side, in many applications, it is also necessary to model and simulate the Joint in details in order to assess the internal reaction forces between pins and holes. The most severe complication is that the Cardan Joint is an overconstrained system. In standard multibody simulations in which the kinematic restraints are modeled introducing constraint equations, this may lead to the indeterminacy of the reaction forces. Moreover, in an overconstrained system, it is impossible to take into account the effect of manufacturing and assembling errors that are always present in the actual parts. In fact, the presence of these errors is somewhat managed by the clearances and elasticity of the components which are in general neglected in a rigid body model with kinematic constraint equations. Scientific literature often reports study on universal Joints by simplifying the mechanism deleting the overabundant constraints [2-6]. Other studies in multibody dynamics introduce the presence of clearances in revolute and cylindrical for overcoming the redundancies [7]. In order to avoid all these problems and to produce a multibody model able to take into account the effects of elasticity and manufacturing errors, a specific modeling technique has been used. All the kinematic pin-hole constraints have been replaced by penalty systems of two intelligent nonlinear piecewise springs by using the approach proposed by Brutti et al. [8] According to this approach, the springs have variable stiffness and damping characteristics in order to take into account different types of contact (line contact, single point contact, two-point contact). Moreover, the Joint forks and cross pins have been modeled using the discrete flexible multibody techniques by splitting the rigid beam-shaped bodies into several smaller bodies connected by matrix spring elements that simulate the elastic compliance of the structure. Several design scenarios have been simulated including geometrical and dimensional errors of components. In particular, four errors have been included: position error on the alignment of the holes of one of the fork, angular misalignment between the holes of one of the fork, angular misalignment on the alignment of two perpendicular pins of the cross, position error of one of the pin of the cross. The influence of these errors on the performance of the Joint have been evaluated in terms of kinematic parameters (velocity and acceleration of the output shaft with respect to the input one) and in terms of dynamic parameters (forces between pin and holes). The results are presented in graphs and tables using dimensionless influence parameters. They can be used for the optimization of the allocation of tolerances and for improving the design of Cardan Joint in specific field such as high-speed mechanisms, precision devices, high-efficiency driveline, etc

  • WITH MANUFACTURING TOLERANCES- Part II
    2008
    Co-Authors: Of Cardan A Joint, L. Vita, E. Pennestrì, Pp Valentini
    Abstract:

    Abstract: This second part of the paper summarizes the methodology for dynamic and mechanical efficiency analysis of a Cardan Joint. The numerical results have been also experimentally validated

  • WITH MANUFACTURING TOLERANCES- Part I
    2008
    Co-Authors: Of Cardan A Joint, L. Vita, E. Pennestrì, Pp Valentini
    Abstract:

    Abstract: A Cardan Joint with manufacturing errors is usually modeled as an RCCC linkage. This first part, after a brief review of dual numbers, summarizes the main equation for the kinematic and static analysis of an RCCC linkage

  • Kinematics, Dynamics and Mechanical Efficiency of a Cardan Joint with Manufacturing Tolerances – Part II
    2006
    Co-Authors: Pennestrì E, Pp Valentini, Vita L
    Abstract:

    This paper deals with the description of innovative methodologies for simulation the dynamic behavior of a Cardan Joint assembly taking into account dimensional errors in revolute Joints. Particular attention has been paid to the computation of mechanical efficiency. This is the second part of a two-part paper

  • A Multibody Dynamic Model of a Cardan Joint with Experimental Validation
    2005
    Co-Authors: Pp Valentini, M. Cavacece, R. Stefanelli, L. Vita
    Abstract:

    Abstract. This investigation deals with the mechanical efficiency of Cardan Joints. The model includes also the effects due to manufacturing and mounting errors and the influence of rotation speed and angular configuration of the Cardan Joint on the efficiency. The Joint has been modeled as an RCCC spatial linkage and the full dynamic analysis has been performed. The equations of motion have been deduced by means both of dual vectors algebra and of classic multibody approach. The results have been compared with experimental ones.

L. Vita - One of the best experts on this subject based on the ideXlab platform.

  • WITH MANUFACTURING TOLERANCES- Part I
    2008
    Co-Authors: Of Cardan A Joint, L. Vita, E. Pennestrì, Pp Valentini
    Abstract:

    Abstract: A Cardan Joint with manufacturing errors is usually modeled as an RCCC linkage. This first part, after a brief review of dual numbers, summarizes the main equation for the kinematic and static analysis of an RCCC linkage

  • WITH MANUFACTURING TOLERANCES- Part II
    2008
    Co-Authors: Of Cardan A Joint, L. Vita, E. Pennestrì, Pp Valentini
    Abstract:

    Abstract: This second part of the paper summarizes the methodology for dynamic and mechanical efficiency analysis of a Cardan Joint. The numerical results have been also experimentally validated

  • A Multibody Dynamic Model of a Cardan Joint with Experimental Validation
    2005
    Co-Authors: Pp Valentini, M. Cavacece, R. Stefanelli, L. Vita
    Abstract:

    Abstract. This investigation deals with the mechanical efficiency of Cardan Joints. The model includes also the effects due to manufacturing and mounting errors and the influence of rotation speed and angular configuration of the Cardan Joint on the efficiency. The Joint has been modeled as an RCCC spatial linkage and the full dynamic analysis has been performed. The equations of motion have been deduced by means both of dual vectors algebra and of classic multibody approach. The results have been compared with experimental ones.

  • mechanical efficiency analysis of a Cardan Joint
    ASME 2004 International Design Engineering Technical Conferences and Computers and Information in Engineering Conference, 2004
    Co-Authors: M. Cavacece, Pp Valentini, E. Pennestrì, L. Vita
    Abstract:

    This investigation concerns with the mechanical efficiency of Cardan Joints. The model includes also the effects due to manufacturing and mounting errors and the influence of rotation speed on the efficiency. The Joint has been modeled as an RCCC spatial linkage and the full dynamic analysis performed by means of dual vectors algebra.Copyright © 2004 by ASME

Vita L - One of the best experts on this subject based on the ideXlab platform.