scholarly journals On the Tripped Rollovers and Lateral Skid in Three-Wheeled Vehicles and Their Mitigation

Vehicles ◽  
2021 ◽  
Vol 3 (3) ◽  
pp. 357-376
Author(s):  
Martín-Antonio Rodríguez-Licea
Keyword(s):  
Soft Soil ◽  
Stability Control ◽  
Measurement Unit ◽  
Common Lyapunov Function ◽  
Problem Resolution ◽  
Active Safety Systems ◽  
Propulsion Control ◽  
Main Components ◽  
Safety Systems ◽  
Wheeled Vehicles

Active safety systems for three-wheeled vehicles seem to be in premature development; in particular, delta types, also known as tuk-tuks or sidecars, are sold with minimal protection against accidents. Unfortunately, the risk of wheel lifting and lateral and/or longitudinal vehicle roll is high. For instance, a tripped rollover occurs when a vehicle slides sideways, digging its tires into soft soil or striking an object. Unfortunately, research is mostly aimed at un-tripped rollovers while most of the rollovers are tripped. In this paper, models for lateral skid tripped and un-tripped rollover risks are presented. Later, independent braking and accelerating control actions are used to develop a dynamic stability control (DSC) to assist the driver in mitigating such risks, including holes/bumps road-scenarios. A common Lyapunov function and an LMI problem resolution ensure robust stability while optimization allows tuning the controller. Numerical and HIL tests are presented. Implementation on a three-wheeled vehicle requires an inertial measurement unit, and independent ABS and propulsion control as main components.

scholarly journals Vehicle Sideslip Angle Estimation Using Two Single-Antenna GPS Receivers

2010 ◽  
Author(s):  
Jong-Hwa Yoon ◽  
Huei Peng
Keyword(s):  
Low Cost ◽  
Longitudinal Velocity ◽  
Stability Control ◽  
Estimation Accuracy ◽  
Measurement Unit ◽  
Sideslip Angle ◽  
Gps Receivers ◽  
Single Antenna ◽  
Active Safety Systems ◽  
Safety Systems

Knowing vehicle sideslip angle accurately is critical for active safety systems such as Electronic Stability Control (ESC). Vehicle sideslip angle can be measured through optical speed sensors, or dual-antenna GPS. These measurement systems are costly (∼$5k to $100k), which prohibits wide adoption of such systems. This paper demonstrates that the vehicle sideslip angle can be estimated in real-time by using two low-cost single-antenna GPS receivers. Fast sampled signals from an Inertial Measurement Unit (IMU) compensate for the slow update rate of the GPS receivers through an Extended Kalman Filter (EKF). Bias errors of the IMU measurements are estimated through an EKF to improve the sideslip estimation accuracy. A key challenge of the proposed method lies in the synchronization of the two GPS receivers, which is achieved through an extrapolated update method. Analysis reveals that the estimation accuracy of the proposed method relies mainly on vehicle yaw rate and longitudinal velocity. Experimental results confirm the feasibility of the proposed method.

scholarly journals Model-Based Slippage Estimation to Enhance Planetary Rover Localization with Wheel Odometry

2021 ◽  
Vol 11 (12) ◽  
pp. 5490
Author(s):  
Anna Maria Gargiulo ◽  
Ivan di Stefano ◽  
Antonio Genova
Keyword(s):  
Inertial Measurement Unit ◽  
Correction Method ◽  
Harsh Environments ◽  
Measurement Unit ◽  
Planetary Rovers ◽  
Model Based ◽  
Accurate Knowledge ◽  
And Control ◽  
Wheeled Vehicles ◽  
Rover Localization

The exploration of planetary surfaces with unmanned wheeled vehicles will require sophisticated software for guidance, navigation and control. Future missions will be designed to study harsh environments that are characterized by rough terrains and extreme conditions. An accurate knowledge of the trajectory of planetary rovers is fundamental to accomplish the scientific goals of these missions. This paper presents a method to improve rover localization through the processing of wheel odometry (WO) and inertial measurement unit (IMU) data only. By accurately defining the dynamic model of both a rover’s wheels and the terrain, we provide a model-based estimate of the wheel slippage to correct the WO measurements. Numerical simulations are carried out to better understand the evolution of the rover’s trajectory across different terrain types and to determine the benefits of the proposed WO correction method.

iB1350: A Generation III.7 Reactor After the Fukushima Daiichi Accident

2016 ◽  
Author(s):  
Takashi Sato ◽  
Keiji Matsumoto ◽  
Kenji Hosomi ◽  
Keisuke Taguchi
Keyword(s):  
Cooling System ◽  
Boiling Water ◽  
Passive Safety ◽  
Active Safety ◽  
Water Reactor ◽  
Airplane Crash ◽  
Passive Safety Systems ◽  
Active Safety Systems ◽  
Fukushima Daiichi ◽  
Safety Systems

iB1350 stands for an innovative, intelligent and inexpensive boiling water reactor 1350. It is the first Generation III.7 reactor after the Fukushima Daiichi accident. It has incorporated lessons learned from the Fukushima Daiichi accident and Western European Nuclear Regulation Association safety objectives. It has innovative safety to cope with devastating natural disasters including a giant earthquake, a large tsunami and a monster hurricane. The iB1350 can survive passively such devastation and a very prolonged station blackout without any support from the outside of a site up to 7 days even preventing core melt. It, however, is based on the well-established proven Advance Boiling Water Reactor (ABWR) design. The nuclear steam supply system is exactly the same as that of the current ABWR. As for safety design it has a double cylinder reinforced concrete containment vessel (Mark W containment) and an in-depth hybrid safety system (IDHS). The Mark W containment has double fission product confinement barriers and the in-containment filtered venting system (IFVS) that enable passively no emergency evacuation outside the immediate vicinity of the plant for a severe accident (SA). It has a large volume to hold hydrogen, a core catcher, a passive flooding system and an innovative passive containment cooling system (iPCCS) establishing passively practical elimination of containment failure even in a long term. The IDHS consists of 4 division active safety systems for a design basis accident, 2 division active safety systems for a SA and built-in passive safety systems (BiPSS) consisting of an isolation condenser (IC) and the iPCCS for a SA. The IC/PCCS pools have enough capacity for 7-day grace period. The IC/PCCS heat exchangers, core and spent fuel pool are enclosed inside the containment vessel (CV) building and protected against a large airplane crash. The iB1350 can survive a large airplane crash only by the CV building and the built-in passive safety systems therein. The dome of the CV building consists of a single wall made of steel and concrete composite. This single dome structure facilitates a short-term construction period and cost saving. The CV diameter is smaller than that of most PWR resulting in a smaller R/B. Each active safety division includes only one emergency core cooling system (ECCS) pump and one emergency diesel generator (EDG). Therefore, a single failure of the EDG never causes multiple failures of ECCS pumps in a safety division. The iB1350 is based on the proven ABWR technology and ready for construction. No new technology is incorporated but design concept and philosophy are initiative and innovative.

The Stability Control of Soft Soil Foundations of Urban Roads According to the Surface Subsidence Monitoring Data

2013 ◽  
Vol 859 ◽  
pp. 222-227
Author(s):  
Hong Jun Liu ◽  
Jin Hua Tan ◽  
Xue Wen Su ◽  
Hao Wu
Keyword(s):  
Soft Soil ◽  
Stability Control ◽  
Surface Subsidence ◽  
Monitoring Data ◽  
Research Results ◽  
The Road ◽  
Future Design ◽  
Left And Right ◽  
Soil Foundation ◽  
The Stability

Two typical monitoring sections are selected for obtaining the change law of the surface subsidence and the settlement after construction of soft soil foundations, and determining the reasonable unloading time. The research results show that the surface settlement rate is large during the filling stage, the rate decreases after the loading and gradually stabilized. The embankment midline settlement is larger than the settlement of the road shoulder which is concluded from the fact that the subsidence of the middle settlement plate is larger than those of the left and right plate. The surface subsidence rate is less than 5mm per month during the two month before unloading according to the data in the tables. The settlement after construction presumed from the middle plate is more significantly larger than that of left and right sides, hence, as the unloading basis of preloading drainage method in soft soil foundation treatment the settlement after construction which is calculated from the midline monitoring data of the road is appropriate. After 6 months the calculated post-construction settlements of the two sections are in the scope of the design requirement since they decrease with preloading time. The reliable basis is provided for the future design and construction of soft foundation in this area through the research results.

scholarly journals Investigation of the relationship between theoretical and actual turning radii of a tracked vehicle using mathematical modeling

2020 ◽  
Vol 1 (4) ◽  
pp. 80-91
Author(s):  
A.A. Stadukhin ◽  
Keyword(s):  
Center Of Mass ◽  
Weight Ratio ◽  
Traction Force ◽  
Plane Motion ◽  
Practical Significance ◽  
Tracked Vehicle ◽  
Literary Sources ◽  
Active Safety Systems ◽  
Turning Radius ◽  
Safety Systems

Introduction. Determination of the traction force and power required in a turn by a tracked ve-hicle is based on analytical dependencies given in classical literary sources. In this case, the de-pendence of the theoretical and actual turning radius is usually not described accurately enough. Subject of study. A study of the dependence of the theoretical and actual turning radius and the influence of the parameters of the undercarriage of the tracked vehicle, the characteristics of the support base and the mode of movement on it was made. Methodology and methods. The study was carried out using a specially developed stationary rotation tracked vehicle (TV) model, which differs by taking into account the redistribution of nor-mal reactions and implementation, allowing one to quickly carry out multifactorial experiments. The rotation of the TV in the model is described as a plane motion of a rigid body. In contrast to the classical approaches, the model allows one to study the rotation of the TV at a speed close to the critical drift. Results and scientific novelty. During computational experiments, the parameters of the chassis of the TV, the properties of the support base, as well as the speed of movement and the actual turn-ing radius were varied. It was found that the classical dependences of the actual and theoretical turning radius need to be refined when driving at a speed close to the critical drift, while the form of the dependence is determined by the height of the center of mass of the TV. Practical significance. These features should be taken into account both when assessing the speed of the vehicle and determining the required thrust-to-weight ratio, and when working on the development of active safety systems for tracked vehicles.

scholarly journals Three-axis air-bearing based platform for small satellite attitude determination and control simulation

2005 ◽  
Vol 3 (03) ◽  
Author(s):  
J. Prado ◽  
G. Bisiacchi ◽  
L. Reyes ◽  
E. Vicente ◽  
F. Contreras ◽  
...  
Keyword(s):  
Attitude Control ◽  
Attitude Determination ◽  
Center Of Mass ◽  
Measurement Unit ◽  
Simulation Platform ◽  
Air Bearing ◽  
Small Satellites ◽  
Main Components ◽  
Free Environment ◽  
And Control

A frictionless environment simulation platform, utilized for accomplishing three-axis attitude control tests in small satellites, is introduced. It is employed to develop, improve, and carry out objective tests of sensors, actuators, and algorithms in the experimental framework. Different sensors (i.e. sun, earth, magnetometer, and an inertial measurement unit) are utilized to assess three-axis deviations. A set of three inertial wheels is used as primary actuators for attitude control, together with three mutually perpendicular magnetic coils intended for desaturation purposes, and as a backup control system. Accurate balancing, through the platform’s center of mass relocation into the geometrical center of the spherical air-bearing, significatively reduces gravitational torques, generating a virtually torque-free environment. A very practical balancing procedure was developed for equilibrating the table in the local horizontal plane, with a reduced final residual torque. A wireless monitoring system was developed for on-line and post-processing analysis; attitude data are displayed and stored, allowing properly evaluate the sensors, actuators, and algorithms. A specifically designed onboard computer and a set of microcontrollers are used to carry out attitude determination and control tasks in a distributed control scheme. The main components and subsystems of the simulation platform are described in detail.

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