Online aircraft velocity and normal acceleration planning for rough terrain following

2017 ◽  
Vol 121 (1244) ◽  
pp. 1561-1577
Author(s):  
Omid Kazemifar ◽  
Ali-Reza Babaei ◽  
Mahdi Mortazavi
Keyword(s):  
Dynamic Model ◽  
Vehicle Dynamics ◽  
Online Algorithm ◽  
Flight Path ◽  
Rough Terrain ◽  
Mountainous Areas ◽  
Level Flight ◽  
Terrain Following ◽  
Workload Reduction ◽  
Normal Acceleration

ABSTRACTThis paper attempts to develop an efficient online algorithm for terrain following in completely unknown rough terrain environments while incorporating aircraft dynamics in the guidance strategy. Unlike most existing works, the proposed algorithm does not generate the flight path directly. The algorithm employs acquired information from the vehicle onboard sensors and rapidly issues appropriate Guidance Commands (GCs) at every point along the way. A suitable dynamic model is developed which takes the lags in the vehicle dynamics into account. The flight path forms gradually as a result of applying the GCs to the vehicle dynamics. Terrain-conforming capability afforded by this approach allows for autonomous and safe low-level flight in unknown mountainous areas. It considerably enhances the autonomy level of the vehicle and in the case of manned aircraft could significantly lead to pilot workload reduction. The proposed scheme is proven to be promising for online applications.

Dynamic model of an air spring and integration into a vehicle dynamics model

2008 ◽  
Vol 222 (10) ◽  
pp. 1813-1825 ◽  
Author(s):  
F Chang ◽  
Z-H Lu
Keyword(s):  
Dynamic Model ◽  
Vehicle Dynamics ◽  
Simulation Method ◽  
Heat Transfer Process ◽  
Spring Model ◽  
Dynamics Model ◽  
Air Spring ◽  
Full Vehicle ◽  
Body Dynamics ◽  
Multi Body

It is worthwhile to design a more accurate dynamic model for air springs, to investigate the dynamic behaviour of an air spring suspension, and to analyse and guide the design of vehicles with air spring suspensions. In this study, a dynamic model of air spring was established, considering the heat transfer process of the air springs. Two different types of air spring were tested, and the experimental results verified the effectiveness of the air spring model compared with the traditional model. The key factors affecting the computation accuracy were studied and checked by comparing the results of the experiments and simulations. The new dynamic model of the air spring was integrated into the full-vehicle multi-body dynamics model, in order to investigate the air suspension behaviour and vehicle dynamics characteristics. The co-simulation method using ADAMS and MATLAB/Simulink was applied to integration of the air spring model with the full-vehicle multi-body dynamics model.

Bi-level Flight Path Planning of UAV Formations with Collision Avoidance

2018 ◽  
Vol 93 (1-2) ◽  
pp. 193-211 ◽  
Author(s):  
Egidio D’Amato ◽  
Massimiliano Mattei ◽  
Immacolata Notaro
Keyword(s):  
Path Planning ◽  
Collision Avoidance ◽  
Flight Path ◽  
Level Flight

Modeling of Track-Wheel-Terrain Interaction for Dynamic Simulation of Tracked Vehicles: Numerical Implementation and Further Results

2001 ◽  
Author(s):  
Zheng-Dong Ma ◽  
N. C. Perkins
Keyword(s):  
Finite Element Method ◽  
Vehicle Dynamics ◽  
Solution Algorithm ◽  
Adaptive Finite Element Method ◽  
Rough Terrain ◽  
Adaptive Finite Element ◽  
Numerical Implementation ◽  
Vehicle Model ◽  
Tracked Vehicles ◽  
Full Vehicle

Abstract This paper extends the methods and results of a previous paper (Ma and Perkins, 1999) on simulating track-wheel-terrain interaction for tracked vehicle dynamics. A new solution algorithm is described that includes an adaptive finite element method for remeshing the track model during simulation. Doing so produces a track model that more accurately describes the mechanics of a track as the vehicle negotiates rough terrain. The model and solution algorithm are illustrated using a full vehicle model of an M1A1 tank.

Substitute Model for Crawler Track Units

2017 ◽  
Author(s):  
Henry Graneß ◽  
Berthold Schlecht
Keyword(s):  
Vehicle Dynamics ◽  
Rough Terrain ◽  
Engineering Structures ◽  
Contact Patch ◽  
Gear Drive ◽  
Driving Speed ◽  
Wide Contact ◽  
D'alembert's Principle

Crawlers for mobilisation of working machines in rough terrain realize considerably high propel power. Furthermore, even heavy engineering structures cause only minor ground loading due to the wide contact patch of the crawler track plate. Typically, the driving speed of crawlers is low. Nevertheless, there is a significant speed droop during travel. The resulting vibrations and thus time variant loads eventuates in altered wear of the crawler’s components, as well as in damage of the travel gear drive and the superstructure of the vehicle. In this paper, a substitute model for crawler units is derived based on D’ALEMBERT’s principle. The model includes the most relevant phenomena of longitudinal crawler vehicle dynamics and hence permits to assess the time variant loads on the components thoroughly.

Evaluation of Novel Concepts for Takeover Control Using Electronically Coupled Sidesticks

2020 ◽  
Vol 65 (1) ◽  
pp. 1-15
Author(s):  
Rodolfo S. Sampaio ◽  
Michael Jones ◽  
Christian Walko
Keyword(s):  
Control Systems ◽  
Flight Control ◽  
The State ◽  
Loss Of Control ◽  
Simulation Environment ◽  
Low Level ◽  
Level Flight ◽  
Mechanical Linkage ◽  
Workload Reduction ◽  
A Priority

The state of the of art in flight control systems geared toward dual-pilot helicopters is the use of active inceptor systems to replace the traditional mechanical linkage between pilot and copilot inceptors. This work investigates the introduction of priority functions, which act to actively decouple inceptors in one control station. This approach has the potential to assist pilots to take over control in low-level flight and aid to mitigate loss-of-control accidents that occur in such conditions. Takeover control maneuvers are tested in a dual-pilot helicopter simulation environment to evaluate two inceptor decoupling methods, namely a priority pushbutton (manual) and a priority force threshold (automatic). Results indicate that the takeover maneuvers were successfully performed in low-level flight without over control (inaccurate control inputs) when using both priority functions. The priority functions led to a workload reduction when compared to a benchmark configuration without inceptor decoupling. Positive ratings in usefulness and satisfaction scales indicate pilot acceptance of the priority functions tested.

Linear Vehicle Dynamics of the TowPlow, a Steerable Articulated Snowplow, and Its Kinematics-Based Steering Control

2015 ◽  
Vol 137 (8) ◽  
Author(s):  
Jae Young Kang ◽  
Steven A. Velinsky
Keyword(s):  
Dynamic Model ◽  
Dynamic Behavior ◽  
Vehicle Dynamics ◽  
Kinematic Analysis ◽  
Control Input ◽  
Steering Control ◽  
Dynamic Simulations ◽  
Linear Dynamic ◽  
Simulation Results ◽  
Stability Limits

The TowPlow is a novel type of snowplow, which consists of a conventional snowplow vehicle and a steerable, plow-mounted trailer. The system is used to plow two typical traffic lanes simultaneously. In this paper, a linear dynamic model is developed in order to investigate the dynamic behavior of this system and its stability limits. Dynamic simulations of various maneuvers are performed, and kinematics-based control is implemented to investigate performance of the trailer's corrective steering. The goal is to ensure that the trailer does not intrude into adjacent lanes during plowing operations while also ensuring that both lanes are sufficiently cleared. Even though the control input is obtained from kinematic analysis, which does not take forces and inertia into account, the simulation results clearly show that the corrective steering helps the TowPlow meet its performance goals.

A Web Based “Virtual Racing Car Championship” to Teach Vehicle Dynamics and Multidisciplinary Design

2011 ◽  
Author(s):  
Francesco Biral ◽  
Fabrizio Zendri ◽  
Enrico Bertolazzi ◽  
Paolo Bosetti ◽  
Marco Galvani ◽  
...  
Keyword(s):  
Optimal Control ◽  
Dynamic Model ◽  
Vehicle Dynamics ◽  
Multidisciplinary Approach ◽  
Dynamic Performance ◽  
Pole Position ◽  
Multidisciplinary Design ◽  
Web Based ◽  
Dynamics And Control ◽  
And Control

A web based VRCC (Virtual Racing Car Championship) application is here presented. The application is intended for educational purposes to teach students a variety of topics of the teaching course “Vehicle Dynamics and Control” in Mechatronics Master Degree Course; the present application forces students to understand the relevant parameters that govern the dynamic performance of racing cars. The application relies on an optimal control library, which is capable of calculating minimum lap times of a racing car on the basis of a comprehensive symbolic description of an open-wheel racing car dynamic model. Students are enrolled in a number of teams competing in a Championship to attain the minimum lap time (i.e., the pole position) on three circuits by choosing the appropriate setup of the racing car. The ranking is based on the best lap time obtained in the qualification session. The application stimulates students to adopt a multidisciplinary approach in a challenging and instructive environment, where they are in a position to apply a broad range of knowledges and abilities they have acquired during the Mechanotronics engineering course.

scholarly journals Turning dynamics analysis of a heavy articulated vehicle by the vehicle planar dynamic model with two steering input signals

2021 ◽  
Vol 4 (2) ◽  
pp. first
Author(s):  
TRAN Huu Nhan ◽  
Nguyễn Văn Hoàng
Keyword(s):  
Dynamic Model ◽  
Vehicle Dynamics ◽  
Single Track ◽  
Steering Angle ◽  
Input Signals ◽  
Articulated Vehicle ◽  
Force Components ◽  
The Stability ◽  
Safety Features ◽  
Lagrange’S Method

The vehicle planar single track dynamic model with two input steering angle parameters is derived by using Lagrange's method with the basis of equations for calculating the tire's force components. Dynamic analysis of a heavy articulated vehicle in case of turing is carried out by the vehicle planar dynamic model, in which two input steering angles are taken into account. Simulation with the selected velocity value to make sure that the stability according to the friction conditions at all axles of the vehicle is satisfied. Turning spacing, lateral forces at each axle of the vehicle are determined and analyzed for all three different cases of steering angles, respectively with steering angle of the semi-trailer is in the same direction, in the opposite direction and is locked or not steered in comparision with the steering angle of the tractor. The obtained results show that the derived model could employ to determine the planar kinematic and dynamic parameters, and analyze the dynamic safety features of an articulated vehicle, too. In addition, the derived mathematical model could also employ to develop a computational model that controls the planar articulated vehicle dynamics.

Sign in / Sign up

Export Citation Format

Share Document