Hydropneumatic Suspension Efficiency in Terms of Teleoperated UGV Research

More often Unmanned Ground Vehicles (UGV) support or replace human in dangerous tasks performing. Usually this operations are realizing in hard conditions in rough terrain. UGVs effectively use determines its ability to obstacle negotiating, to reach high adhesion force, drawbar pull and extra longitudinal and lateral stability of UGV. Variety missions determining of use in UGVs reconfigurable and control suspension system. It is able to meet this requirement thanks to use hydropneumatic components in them suspension system. However currently it is very hard to developed characteristic of such a suspension systems. In literature there is no clear guidelines for suspension systems of teleoperated UGVs. This paper presents results of hydropneumatic suspension system research on heavy UGV.

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Hybrid Modelling and Sliding Mode Control of Semi-Active Suspension Systems for Both Ride Comfort and Road-Holding

Symmetry ◽

10.3390/sym12081286 ◽

2020 ◽

Vol 12 (8) ◽

pp. 1286

Author(s):

Ayman Aljarbouh ◽

Muhammad Fayaz

Keyword(s):

Hybrid Model ◽

Ride Comfort ◽

Sliding Mode ◽

Active Suspension ◽

Suspension System ◽

Vehicle Suspension ◽

Suspension Systems ◽

Active Suspension Systems ◽

System Components ◽

And Control

Rigorous model-based design and control for intelligent vehicle suspension systems play an important role in providing better driving characteristics such as passenger comfort and road-holding capability. This paper investigates a new technique for modelling, simulation and control of semi-active suspension systems supporting both ride comfort and road-holding driving characteristics and implements the technique in accordance with the functional mock-up interface standard FMI 2.0. Firstly, we provide a control-oriented hybrid model of a quarter car semi-active suspension system. The resulting quarter car hybrid model is used to develop a sliding mode controller that supports both ride comfort and road-holding capability. Both the hybrid model and controller are then implemented conforming to the functional mock-up interface standard FMI 2.0. The aim of the FMI-based implementation is to serve as a portable test bench for control applications of vehicle suspension systems. It fully supports the exchange of the suspension system components as functional mock-up units (FMUs) among different modelling and simulation platforms, which allows re-usability and facilitates the interoperation and integration of the suspension system components with embedded software components. The concepts are validated with simulation results throughout the paper.

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Traversability Assessment and Trajectory Planning of Unmanned Ground Vehicles with Suspension Systems on Rough Terrain

Sensors ◽

10.3390/s19204372 ◽

2019 ◽

Vol 19 (20) ◽

pp. 4372 ◽

Cited By ~ 3

Author(s):

Kai Zhang ◽

Yi Yang ◽

Mengyin Fu ◽

Meiling Wang

Keyword(s):

Trajectory Planning ◽

Tracking Error ◽

Assessment Method ◽

Rough Terrain ◽

Ground Vehicles ◽

Ground Vehicle ◽

Suspension Systems ◽

Vehicle Motion ◽

Initial Path ◽

Method Of Lagrange Multipliers

This paper presents a traversability assessment method and a trajectory planning method. They are key features for the navigation of an unmanned ground vehicle (UGV) in a non-planar environment. In this work, a 3D light detection and ranging (LiDAR) sensor is used to obtain the geometric information about a rough terrain surface. For a given SE(2) pose of the vehicle and a specific vehicle model, the SE(3) pose of the vehicle is estimated based on LiDAR points, and then a traversability is computed. The traversability tells the vehicle the effects of its interaction with the rough terrain. Note that the traversability is computed on demand during trajectory planning, so there is not any explicit terrain discretization. The proposed trajectory planner finds an initial path through the non-holonomic A*, which is a modified form of the conventional A* planner. A path is a sequence of poses without timestamps. Then, the initial path is optimized in terms of the traversability, using the method of Lagrange multipliers. The optimization accounts for the model of the vehicle’s suspension system. Therefore, the optimized trajectory is dynamically feasible, and the trajectory tracking error is small. The proposed methods were tested in both the simulation and the real-world experiments. The simulation experiments were conducted in a simulator called Gazebo, which uses a physics engine to compute the vehicle motion. The experiments were conducted in various non-planar experiments. The results indicate that the proposed methods could accurately estimate the SE(3) pose of the vehicle. Besides, the trajectory cost of the proposed planner was lower than the trajectory costs of other state-of-the-art trajectory planners.

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A novel approach to design and control of an active suspension using linear pump control–based hydraulic system

Proceedings of the Institution of Mechanical Engineers Part D Journal of Automobile Engineering ◽

10.1177/0954407019882223 ◽

2019 ◽

Vol 234 (5) ◽

pp. 1224-1248

Author(s):

Jeongwoo Lee ◽

Kwangseok Oh ◽

Kyongsu Yi

Keyword(s):

Vehicle Dynamics ◽

Hydraulic System ◽

Cost Effective ◽

Active Suspension ◽

Linear Motor ◽

Suspension System ◽

Suspension Systems ◽

Active Suspension Systems ◽

Actuator System ◽

And Control

This paper presents a novel design and control method of an active suspension system using a linear pump control–based hydraulic system for a cost-effective application. Various active suspension systems have been proposed and applied to vehicles due to its ability to improve ride comfort and handling performance even though these active suspension systems are not popular because of their complexity, high cost, heavyweight, and low power efficiency. A new type of active suspension actuator system was designed and validated herein based on the methods of actuator sizing and modified control scheme to address the aforementioned issues. System power capability has been analyzed under various dynamics and road conditions. Active suspension actuator components have been designed based on the results. The electro-hydraulic system is powered by a battery to reduce the energy consumption of the system; hence, it is operated by torque on demand. A double-acting linear hydraulic motor pump with a dual rack and pinion has been proposed for hydraulic force control with a simple on/off switch operation. The actuator force has been controlled by continuous linear motor pump displacement control via torque control using a three-phase synchronous brushless alternative current motor. Dynamic performance evaluation of the actuator system has been conducted using AMESIM and actual rig test. Active height and roll control algorithms for the enhancement of vehicle dynamics considering actuator dynamics have also been developed and validated through the rig and real vehicle tests. The evaluation results showed that the linear motor pump–based active suspension system performs as well as the previous complicated hydraulic active suspension system. The new active system proposed in this study was able to improve the vehicle dynamics using cost-effective actuation system significantly.

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