Motorcycle Analytical Modeling Including Tire–Wheel Nonuniformities for Ride Comfort Analysis

2017 ◽  
Vol 45 (2) ◽  
pp. 101-120 ◽  
Author(s):  
Matheus de B. Vallim ◽  
José M. C. Dos Santos ◽  
Argemiro L. A. Costa
Keyword(s):  
Degrees Of Freedom ◽  
Analytical Modeling ◽  
Ride Comfort ◽  
Experimental Tests ◽  
Rotational Frequency ◽  
Analytical Models ◽  
Vertical Force ◽  
Lumped Mass ◽  
Multi Body ◽  
4 Degrees Of Freedom

ABSTRACT The transmission of vibrations in motorcycles and their perception by the passengers are fundamental in comfort analysis. Tire nonuniformities can generate self-excitations at the rotational frequency of the wheel and contribute to the ride vibration environment. In this work a multi-body motorcycle model is built to evaluate the ride comfort with respect to tire nonuniformities. The aim is to obtain a multi–degrees-of-freedom dynamic model that includes both the contributions of the motorcycle and tire–wheel assembly structures. This representation allows the tire nonuniformities to predict the vertical force variations on the motorcycle and can be used through a root mean square acceleration evaluation for ride comfort analysis. The motorcycle model proposed is a 10-degrees-of-freedom system, where each tire–wheel is a 4-degrees-of-freedom model. The tire–wheel assemblies include two types of nonuniformities: lumped mass imbalance and radial run-out. Simulations of analytical models are compared with experimental tests.

A new coordinated control strategy for tracked vehicle ride comfort

2017 ◽  
Vol 232 (3) ◽  
pp. 330-341 ◽  
Author(s):  
Jianfeng Li ◽  
Amir Khajepour ◽  
Yanjun Huang ◽  
Hong Wang ◽  
Chen Tang ◽  
...  
Keyword(s):  
Control Strategy ◽  
Degrees Of Freedom ◽  
Target Location ◽  
Ride Comfort ◽  
Sliding Mode ◽  
Coordinated Control ◽  
Magnetorheological Damper ◽  
Vertical Acceleration ◽  
Tracked Vehicle ◽  
Multi Body

To improve tracked vehicle ride comfort and minimize weapon's vibration, a coordinated control strategy is developed for tracked vehicles' semi-active suspension systems. A model with eight degrees-of-freedom for a tracked vehicle equipped with magnetorheological dampers is established, and is followed by the formulation of a sliding mode controller. The proposed control algorithm is a localized-based controller that can change its target location in the tracked vehicle to where it is needed most. A co-simulation system model including a six-wheel tracked vehicle multi-body dynamics model, coordinated control strategy, and magnetorheological damper force allocator is developed to analyze the ride performance under bump and random road excitations. The simulation results demonstrate that the proposed strategy is very effective in improving the vehicle's ride performance and is much better than the traditional skyhook controllers. The innovation of this paper can be concluded as the coordinated control strategy can simultaneously improve vertical acceleration and pitch acceleration for the hull, which is of great importance for combat situations.

Modeling and Simulation of Motorcycle Ride Comfort Based on Bump Road

2010 ◽  
Vol 139-141 ◽  
pp. 2643-2647 ◽  
Author(s):  
Dong Mei Yuan ◽  
Xiao Mei Zheng ◽  
Ying Yang
Keyword(s):  
Degrees Of Freedom ◽  
Ride Comfort ◽  
Lagrange Equation ◽  
Equations Of Motion ◽  
Vertical Displacement ◽  
Dynamics Model ◽  
Body Dynamics ◽  
Space Formulation ◽  
Simulation Results ◽  
Multi Body

Through analyzing the motion when motorcycle runs on the bump road, the 5-DOF multi-body dynamics model of motorcycle is developed, the degrees of freedom include vertical displacement of sprung mass, rotation of sprung mass, vertical displacement of driver, and vertical displacement of front and rear suspension under sprung mass. According to Lagrange Equation, the differential equations of motion and state-space formulation are derived. Then bump road is simulated by triangle bump, and input displacement is programmed by MATLAB. With the input of bump road, motorcycle ride comfort is simulated, and the simulation results are verified by experiment results combined with two channels tire-coupling road simulator. It indicates that the simulation results and experiment results match well; the 5-DOF model has guidance for development of motorcycle ride comfort.

scholarly journals A novel forestry chassis with an articulated body with 3 degreesof freedom and installed luffingwheel-legs

2018 ◽  
Vol 10 (1) ◽  
pp. 168781401774710 ◽  
Author(s):  
Yue Zhu ◽  
Jiangming Kan ◽  
Wenbin Li ◽  
Feng Kang
Keyword(s):  
Complex Terrain ◽  
Mechanical Model ◽  
Degrees Of Freedom ◽  
Ride Comfort ◽  
Hydraulic Cylinder ◽  
The Other ◽  
Dynamics Simulation ◽  
Forest Industry ◽  
Body Dynamics ◽  
Multi Body

One of the challenging problems in the forest industry is to develop a chassis that is well-adapted to the complex terrain conditions in the forest. In this article, a novel forestry chassis with an articulated body with 3 degrees of freedom and installed luffing wheel-legs (FC-3DOF&LW) is proposed, and the mechanical model of the luffing wheel-leg is built. Based on the mechanical model, the hydraulic cylinder velocity that involves the wheel-leg luffing is calculated. The process of surmounting the obstacle is presented by multi-body dynamics simulation. To demonstrate the improvement of ride comfort, the other simulation of the chassis with an articulated body with 3 degrees of freedom (FC-3DOF) is contrasted in multi-dynamics software. The final result shows that curves of barycenter displacement for FC-3DOF&LW with the front and rear frames are well matched when the front frame surmounts the obstacle; in particular, the barycenter displacement is almost stable when the rear frame surmounts the obstacle. The maximum rotated angle of the articulated joint reaches almost 37° without the luffing wheel-leg, whereas it is only 4° with FC-3DOF&LW, a decrease of 89.1%. Moreover, the acceleration trend for FC-3DOF&LW is more stable than that for FC-3DOF.

Influence of balanced suspension on handling stability and ride comfort of off-road vehicle

2020 ◽  
pp. 095440702097619
Author(s):  
Qiang Chen ◽  
Xian-Xu Frank Bai ◽  
An-Ding Zhu ◽  
Di Wu ◽  
Xue-Cai Deng ◽  
...  
Keyword(s):  
Ride Comfort ◽  
Dynamic Performance ◽  
Experimental Tests ◽  
Installation Space ◽  
Dynamics Model ◽  
Vehicle Performance ◽  
Body Dynamics ◽  
Pneumatic Suspension ◽  
New Type ◽  
Multi Body

Handing stability and ride comfort, basic indexes to evaluate vehicle performance, usually cannot be guaranteed simultaneously. Given the contradiction between the two indexes, a new type of suspension – balanced suspension, has attracted wide attentions for years. Balanced suspensions are a device that converts the movement of a wheel into force at the other wheels through a mechanical or hydraulic structure, which might improve ride comfort/handling stability while maintaining the handling stability/ride comfort. As the hydraulically interconnected suspension and hydro-pneumatic suspension show disadvantages of high cost and high installation space requirement, a specific balanced suspension which is connected through a mechanical structure is presented and thoroughly analyzed in this paper. The balanced suspension connects the front and rear suspension motion of the vehicle by means of the lever mechanical connection structure to obtain the comprehensive performance of enhanced vehicle’s ride comfort and handling stability. The half-vehicle mathematical model for ride comfort and the multi-body dynamics model for handling stability are established for the comparison and analysis of the dynamic performance of vehicle when the balanced suspension on and off. In addition, experimental tests of the modified vehicle prototypes when the balanced suspension on and off on the ride comfort and handling stability are conducted. Similar with the simulation results, experimental tests show that the handling stability is nearly unchanged while the ride comfort improves about 15.9% when the balanced suspension is on.

A Comparison of Quarter, Half and Full Vehicle Models With Experimental Ride Comfort Data

2015 ◽  
Author(s):  
Herman A. Hamersma ◽  
Schalk Els
Keyword(s):  
Degrees Of Freedom ◽  
Ride Comfort ◽  
Center Of Mass ◽  
Vehicle Body ◽  
Vehicle Model ◽  
Full Vehicle ◽  
Computational Capability ◽  
Quarter Car ◽  
Multi Body ◽  
Vertical Translation

The ride comfort of a vehicle is one of the first parameters used to evaluate its performance. Ride comfort has been one of the important research topics since the dawn of the automobile. With the improvement in computational capability, vehicle engineers have modeled vehicles with increasing complexity. Initially vehicles were simplified to quarter car models, where a quarter of the vehicle was modeled with two degrees of freedom (the vertical translation of the sprung and unsprung masses). The “pitch-bounce” model has four degrees of freedom, representing the pitch rotation and vertical translation (bounce) of the vehicle body and chassis and the vertical translation of the front and rear axles and wheels. Finally, with the development of multi-body systems (MBS) software, there is the possibility to model the full vehicle with suspension kinematics and numerous degrees of freedom. The full vehicle model used for this study has 15 unconstrained degrees of freedom and experimentally determined center of mass and inertias. This paper compares the response of a quarter car, pitch-bounce and full vehicle model with the measured response of an actual vehicle.

scholarly journals Development and assessment of a telesonography system for musculoskeletal imaging

2021 ◽  
Vol 5 (1) ◽  
Author(s):  
Mohammed Obaid ◽  
Qianwei Zhang ◽  
Scott J. Adams ◽  
Reza Fotouhi ◽  
Haron Obaid
Keyword(s):  
Degrees Of Freedom ◽  
Ultrasound Images ◽  
Ultrasound Probe ◽  
Rural And Remote ◽  
Significant Delay ◽  
Remote Communities ◽  
Internet Connection ◽  
Good For ◽  
4 Degrees Of Freedom

Abstract Background Telesonography systems have been developed to overcome barriers to accessing diagnostic ultrasound for patients in rural and remote communities. However, most previous telesonography systems have been designed for performing only abdominal and obstetrical exams. In this paper, we describe the development and assessment of a musculoskeletal (MSK) telesonography system. Methods We developed a 4-degrees-of-freedom (DOF) robot to manipulate an ultrasound probe. The robot was remotely controlled by a radiologist operating a joystick at the master site. The telesonography system was used to scan participants’ forearms, and all participants were conventionally scanned for comparison. Participants and radiologists were surveyed regarding their experience. Images from both scanning methods were independently assessed by an MSK radiologist. Results All ten ultrasound exams were successfully performed using our developed MSK telesonography system, with no significant delay in movement. The duration (mean ± standard deviation) of telerobotic and conventional exams was 4.6 ± 0.9 and 1.4 ± 0.5 min, respectively (p = 0.039). An MSK radiologist rated quality of real-time ultrasound images transmitted over an internet connection as “very good” for all telesonography exams, and participants rated communication with the radiologist as “very good” or “good” for all exams. Visualisation of anatomic structures was similar between telerobotic and conventional methods, with no statistically significant differences. Conclusions The MSK telesonography system developed in this study is feasible for performing soft tissue ultrasound exams. The advancement of this system may allow MSK ultrasound exams to be performed over long distances, increasing access to ultrasound for patients in rural and remote communities.

scholarly journals A New Approach of Soft Joint Based on a Cable-Driven Parallel Mechanism for Robotic Applications

Mathematics ◽  
2021 ◽  
Vol 9 (13) ◽  
pp. 1468
Author(s):  
Luis Nagua ◽  
Carlos Relaño ◽  
Concepción A. Monje ◽  
Carlos Balaguer
Keyword(s):  
Parallel Mechanism ◽  
Degrees Of Freedom ◽  
Kinematic Model ◽  
Experimental Tests ◽  
Humanoid Robots ◽  
Inverse Kinematic ◽  
Element Analysis ◽  
New Approach ◽  
Flexible Polymer ◽  
The Mathematical Model

A soft joint has been designed and modeled to perform as a robotic joint with 2 Degrees of Freedom (DOF) (inclination and orientation). The joint actuation is based on a Cable-Driven Parallel Mechanism (CDPM). To study its performance in more detail, a test platform has been developed using components that can be manufactured in a 3D printer using a flexible polymer. The mathematical model of the kinematics of the soft joint is developed, which includes a blocking mechanism and the morphology workspace. The model is validated using Finite Element Analysis (FEA) (CAD software). Experimental tests are performed to validate the inverse kinematic model and to show the potential use of the prototype in robotic platforms such as manipulators and humanoid robots.

Numerical and Experimental Approaches to Investigate the Stability of a Motorcycle Vehicle

2006 ◽  
Author(s):  
Federico Cheli ◽  
Marco Bocciolone ◽  
Marco Pezzola ◽  
Elisabetta Leo
Keyword(s):  
Degrees Of Freedom ◽  
Structural Parameters ◽  
Experimental Tests ◽  
Roll Angle ◽  
Longitudinal Motion ◽  
Reference Trajectory ◽  
Steering Angle ◽  
Steady State Condition ◽  
The Stability ◽  
Linearized Model

The study of motorcycle’s stability is an important task for the passenger’s safety. The range of frequencies involved for the handling stability is lower than 10 Hz. A numerical model was developed to access the stability of a motorcycle vehicle in this frequency range. The stability is analysed using a linearized model around the straight steady state condition. In this condition, the vehicle’s vertical and longitudinal motion are decoupled, hence the model has only four degrees of freedom (steering angle, yaw angle, roll angle and lateral translation), while longitudinal motion is imposed. The stability was studied increasing the longitudinal speed. The input of the model can be either a driver input manoeuvre (roll angle) or a transversal component of road input able to excite the vibration modes. The driver is introduced in the model as a steering torque that allows the vehicle to follow a reference trajectory. To validate the model, experimental tests were done. To excite the vehicle modes, the driver input was not taken into account considering both the danger for the driver and the repeatability of the manoeuvre. Two different vehicle configurations were tested: vehicle 1 is a motorcycle [7] and vehicle 2 is a scooter. Through the use of the validated model, a sensitivity analysis was done changing structural (for example normal trail, steering angle, mass) and non structural parameters (for example longitudinal speed).

Adaptive Control of a Sliding Seat Using Magnetorheological Energy Absorbers

2010 ◽  
Author(s):  
Min Mao ◽  
Norman M. Wereley ◽  
Alan L. Browne
Keyword(s):  
Adaptive Control ◽  
Degrees Of Freedom ◽  
Adaptive Controller ◽  
Degree Of Freedom ◽  
Lumped Mass ◽  
Adaptive Controllers ◽  
Bingham Number ◽  
Control Objective ◽  
Payload Mass ◽  
Energy Absorbers

Feasibility of a sliding seat utilizing adaptive control of a magnetorheological (MR) energy absorber (MREA) to minimize loads imparted to a payload mass in a ground vehicle for frontal impact speeds as high as 7 m/s (15.7 mph) is investigated. The crash pulse for a given impact speed was assumed to be a rectangular deceleration pulse having a prescribed magnitude and duration. The adaptive control objective is to bring the payload (occupant plus seat) mass to a stop using the available stroke, while simultaneously accommodating changes in impact velocity and occupant mass ranging from a 5th percentile female to a 95th percentile male. The payload is first treated as a single-degree-of-freedom (SDOF) rigid lumped mass, and two adaptive control algorithms are developed: (1) constant Bingham number control, and (2) constant force control. To explore the effects of occupant compliance on adaptive controller performance, a multi-degree-of-freedom (MDOF) lumped mass biodynamic occupant model was integrated with the seat mass. The same controllers were used for both the SDOF and MDOF cases based on SDOF controller analysis because the biodynamic degrees of freedom are neither controllable nor observable. The designed adaptive controllers successfully controlled load-stroke profiles to bring payload mass to rest in the available stroke and reduced payload decelerations. Analysis showed extensive coupling between the seat structures and occupant biodynamic response, although minor adjustments to the control gains enabled full use of the available stroke.

scholarly journals Light-assisted electrospinning monitoring for soft polymeric nanofibers

2020 ◽  
Vol 10 (1) ◽  
Author(s):  
Dario Lunni ◽  
Goffredo Giordano ◽  
Francesca Pignatelli ◽  
Carlo Filippeschi ◽  
Stefano Linari ◽  
...  
Keyword(s):  
Real Time ◽  
Electrospun Fiber ◽  
Correlation Coefficients ◽  
Experimental Tests ◽  
Electrospinning Process ◽  
Analytical Models ◽  
Diameter Distribution ◽  
Soft Systems ◽  
Light Coupling ◽  
Waveguide Length

Abstract A real-time tool to monitor the electrospinning process is fundamental to improve the reproducibility and quality of the resulting nanofibers. Hereby, a novel optical system integrated through coaxial needle is proposed as monitoring tool for electrospinning process. An optical fiber (OF) is inserted in the inner needle, while the external needle is used to feed the polymeric solution (PEO/water) drawn by the process. The light exiting the OF passes through the solution drop at the needle tip and gets coupled to the electrospun fiber (EF) while travelling towards the nanofibers collector. Numerical and analytical models were developed to assess the feasibility and robustness of the light coupling. Experimental tests demonstrated the influence of the process parameters on the EF waveguide properties, in terms of waveguide length (L), and on the nanofibers diameter distribution, in terms of mean $$\widehat{D}$$ D ^ and normalized standard deviation $$\chi$$ χ . Data analysis reveals good correlation between L and $$\widehat{D}, \chi$$ D ^ , χ (respectively maximum correlation coefficients of $${\rho }_{L,\widehat{D}}$$ ρ L , D ^ = 0.88 and $${\rho }_{L,\chi }$$ ρ L , χ = 0.84), demonstrating the potential for effectively using the proposed light-assisted technology as real-time visual feedback on the process. The developed system can provide an interesting option for monitoring industrial electrospinning systems using multi- or moving needles with impact in the scaling-up of innovative nanofibers for soft systems.

Sign in / Sign up

Export Citation Format

Share Document