Center Of Gravity Height Research Articles

Estimation of Tire Load and Vehicle Parameters Using Intelligent Tires Combined With Vehicle Dynamics

This article focuses on the estimation of static/ dynamic tire load and vehicle parameters using intelligent tires and vehicle dynamics. This study is conducted to improve and ensure the performance of advanced vehicle control using accurate vehicle and tire states. The contact angle between tire and road surface is calculated by an intelligent tire and is used for tire load estimation. The tire load estimation results are validated by the flexible ring tire model. For a fast sampling rate and high robustness, a new estimation algorithm, which combines intelligent tire and vehicle dynamics, is proposed in this article. Not only the tire load but also the vehicle parameters, such as total mass, center of gravity point (CG point), and center of gravity height (CG height), are estimated by the proposed estimation algorithm. The proposed estimation algorithm is verified by an indoor test using Flac trac (tire test system) and a real-time test using AutoBox III. In short, the estimation algorithm proposed in this article can estimate static/dynamic tire load and vehicle parameters with a fast sampling rate and high robustness.

Hydrodynamic Study and Performance Analysis of the OC4-DeepCWind Platform by CFD Method

(1) The RAOs of OC4-DeepCWind platform motions are more sensitive to the low-frequency wave than the high-frequency wave. The nonlinear motion responses for platform heave and pitch motions are comparatively remarkable. (2) The pitch motion of OC4-DeepCWind platform is much more apparently influenced by the height of center of gravity (COG) than surge and heave motions. The lower COG height within a suitable range leads to a smaller fluctuation amplitude of platform pitch motion in waves. (3) A large horizontal displacement abruptly occurs to the OC4-DeepCWind platform when one mooring line is failure. The risk of failure for the other mooring lines significantly increases. To better understand the hydrodynamic performance of a floating support platform in various wave environments, a two-phase CFD solver naoe-FOAM-SJTU based on the open source CFD toolbox OpenFOAM is applied to investigate the hydrodynamic characteristics and motion performance of the OC4-DeepCWind platform. Moreover, the restoring force and moment of mooring lines are simulated using the solver in time domain. The studies of grid sensitivity and time step refinement are first conducted to determine an appropriate time step and mesh size. Then hydrodynamic responses of the floater in free-decay tests are analyzed and compared with experimental data, and the motion performance of the platform in regular waves with different parameters is also investigated. In addition, the platform motion responses with one mooring line broken and different heights of center of gravity are explored. It is shown that simulation results have good agreement with published data, and several conclusions can be drawn through the study. The RAOs of platform motions are found to be more sensitive to the low-frequency wave than the high-frequency wave. Nonlinear motion responses are comparatively remarkable in platform heave and pitch motions. Besides, the lower height of center of gravity within a suitable range is benefit to the stability of floating platform. Survival condition with broken mooring line should be paid enough attention to avoid the failure of other mooring lines.

Effects of fatigue on biomechanics of forehand smash in badminton

Sports fatigue will cause deformation of actions. In this study, badminton was analyzed, and the influence which was brought by fatigue was studied from the perspective of biomechanics. The forehand smash of professional badminton athletes under normal and fatigue states was tested. The biomechanical indexes of athletes were obtained by infrared remote shooting test system and plantar pressure test system for comparison. The results showed that the forehand smash effect of athletes was significantly worse under fatigue state, the maximum gravity center height decreased to 1.22 ± 0.14 m, and the maximum gravity center speed decreased to 2.33 ± 0.12 m/s, which showed significant decreases compared to the normal state (P< 0.05). Moreover the maximum velocity of the right upper arm, right forearm, elbow joint, wrist joint and knee joint decreased significantly (P< 0.5), the maximum angle of the right hip joint, knee joint and left ankle joint also decreased significantly. The pressure of the inner side of the forefoot and the pressure in the middle of the forefoot increased (P< 0.05). The biomechanical analysis of forehand smash under fatigue condition reveals the relationship between fatigue and movement, which provides some scientific bases for the reasonable control of sports load.

The effects of handle height, load's CoG height and load on lifting tasks

The effect of the load's center of gravity (CoG) on manual materials handling tasks received little attention in literature. The motivation of this study was to examine the effects of handle height, load's CoG height and load on lifting tasks. Eighteen participants performed 27 lifting tasks, including 3 handle heights (10, 30, 50 cm) by 3 load's CoG heights (10, 30, 50 cm) by 3 loads (7, 14, 21 kg). The lifting time, maximum box tilt angle, muscular activity (brachioradialis, biceps brachii, deltoid, and erector spinae), maximum CoP velocity, and lifting difficulty were measured. The results showed that lifting time and maximum box tilt angle decreased with increasing handle height. Middle handle height (30 cm) resulted in the lowest muscular activity, maximum CoP velocity, and lifting difficulty. Low load's CoG height decreased lifting time, maximum box tilt angle, muscular activity, and lifting difficulty, however, it also increased maximum CoP velocity. In addition, high load increased lifting time, maximum box tilt angle, muscular activity, maximum CoP velocity, and lifting difficulty.

The optimization of automated goods dynamic allocation and warehousing model

In the development of modern logistics, the role of automated cargo warehousing is gradually reflected, which is essential for the automatic distribution of goods. This paper briefly introduced the automatic location allocation model and the particle swarm optimization (PSO) algorithm used to optimize the model. At the same time, it introduced the concept of genetic operator and multi-group co-evolution to improve the algorithm, and then the simulation analysis of standard PSO and improved PSO was performed on MATLAB software. The results showed that the improved PSO iterated fewer times and get better solution sets; compared with the manual allocation scheme, the improved PSO calculation reduced more warehousing time, lowered more center of gravity height, and improved shelf stability. In summary, the improved PSO algorithm can effectively optimize the automated goods dynamic allocation and warehousing model.

Combining ability of cytoplasmic male sterility on yield and agronomic traits of sorghum for grain and biomass dual-purpose use

Sorghum [Sorghum bicolor (L.) Moench] is a high-yielding C4 crop used not only to produce grains for food, feed, and industrial uses but also biomass (i.e., leaf and stem) for biofuel production. To take better advantage of its heterosis for both grain and biomass dual-purpose use, the combining ability of 34 cytoplasmic male sterile lines (female) were tested with 3 cytoplasmic male fertile restore lines (male) using the North Carolina design (NCⅡ) at Zhuozhou (Hebei province) and Jiexiu (Shanxi province) in northern China for two years (2017 and 2018). The hybrids exhibited a grain yield of 0.3 ∼ 14.0 t ha−1 and had an aboveground biomass yield (AGBY) of 9.6 ∼ 109.9 t ha−1 across both sites in 2017 and 2018. The genotype and site × genotype interactions significantly affected the yield and agronomic traits. With respect to their grain and biomass dual-purpose use, the tested 34 female lines revealed that plant height, gravity center height, productive tiller rate, and harvest index were strongly general combining ability (GCA) sensitive. Stem width, days to maturity, AGBY, and grain width were medium GCA-sensitive; and grain yield, 100-grain weight, days between heading and maturity, and grain bulk density were weakly GCA-sensitive. The GCA effect on grain yield was positive and significantly correlated with productive tiller rate, AGBY, and harvest index. The GCA effect on AGBY had a positive, significant correlation with plant height, gravity center height, productive tiller rate, and days to maturity; but the effect was negatively correlated with 100-grain weight and grain width. For tested traits, the additive gene effects strongly predominated over the non-additive genes for tested traits. Plant height was the most GCA-sensitive trait and the most important for biomass production. Female lines AMP418, AMP431, AMP434, AMP443, AMP495, AMP496 and the male line X097 were selected as being high-GCA effect germplasm. These selections from newly introduced cytoplasmic male sterile lines hold promise for accelerating the genetic improvement of sorghum for its dual-purpose use as grain for food and biomass for biofuel.

An Integrated Observer for Real-Time Estimation of Vehicle Center of Gravity Height

This paper introduces a new integrated observer for estimating the vehicle center of gravity (CG) height in real time. It can assist the vehicle in monitoring the real-time rollover risk and improving the performance of vehicle safety control systems. The proposed integrated observer consists of three parts: a linearized recursive least square (LRLS) algorithm on vehicle longitudinal motion, an adaptation law on vehicle lateral motion, and observer synthesis. First, the LRLS algorithm performs estimation of vehicle mass and CG height during longitudinal braking and exploits the characteristic that normalized longitudinal tire stiffness is the same in the front and rear axles. Second, the adaptation law, accompanied by a roll angle observer, estimates CG height on the vehicle lateral motion based on Lyapunov stability analysis. It includes the following contributions: verification of robustness to the vehicle mass estimation error and prevention of integration drift. Finally, in the observer synthesis, the final estimation of CG height combining the above two results is derived. The overall estimation algorithm has high practicality due to the following features. 1) CG height can be obtained on both longitudinal and lateral motions of the vehicle. This point leads to a fast convergence rate in CG height estimation. 2) The fact that it does not cause any computational burden issues in real-time implementation is also a great advantage in terms of practicality. 3) It utilizes only readily available sensors. An experimental study with various driving scenarios evaluates the effectiveness of the proposed algorithm in real-car application.

Analysis and simplified modelling of simulation of tests for medium-duty truck collision with twin anti-ram bollards

An actual test of medium-duty truck collision with twin anti-ram bollards of steel tube is analysed and simulated with different mass-spring-damper models to study bollard design requirements. Test data is obtained from test report of a medium-duty truck crashed into two fixed twin bollards at speed 78.3 km/h. Maximum impact load and impact height at that time is important in the analysis. Bollard height should be close to or larger than the vehicle’s centre of gravity height to avoid climbing of the truck on the bollard. However, increasing impact height yields also increase in failure risk of bollard. Foundation is also critical in success of the bollard in successfully stopping the vehicle. The bollard should be fixed to the frame embedded in the concrete foundation so that the deformation in concrete be minimised. The bollard should be so stiff to stop the vehicle while most of the impact energy is absorbed by the vehicle through deformation of its frontal sections. A single-degree freedom linear mass-spring-damper model is the simplest model, but its results are not in line with test data. Single-degree non-linear model simulates the peak load but not the load history. However, using engine mass instead of truck mass in the single-degree model provides acceptable impact force data for the bollard. Two-degree freedom mass-spring damper linear model seems to simulate both truck’s and bollard’s deformation in a good manner. Non-linear analysis simulates the collision in a more realistic way, but it requires more data to be determined with testing.

A real-time optimal energy-saving walking pattern generator based on gradient descent method and linear quadratic control

ABSTRACTMany recent approaches have successfully generated a stable walking pattern for biped robots, but discussions about its optimization are relatively few. In this paper, a Center of Gravity (COG) trajectory optimization method is proposed to minimize the cost function of joint torque, joint limit, and joint speed limit. The linear quadratic control-based inverted pendulum controller optimizes the COG trajectories in sagittal and lateral directions with the COG height trajectory. The COG height trajectory is optimized by finding the derivative of the cost function with respect to the COG height offline. Then the proposed walking pattern generator builds the COG height trajectory database of different walking steps for online connection of a walking pattern. The walking pattern generator is verified by experiments and simulations of different step cycles with our humanoid robot, NINO, and it can clearly reduce the required joint torque of the robot while walking. In addition, compared with the fixed COG height trajectory, the energy consumption is reduced by 14% from the experimental results. Thus, the method succeeds in generating a more energy-saving walking pattern.

On the estimation of centre of gravity height in vertical jumping

The purpose of this study was to compare three different methods for the estimation of vertical jump height and to reveal errors in maximum height of the centre of gravity (CG) that emerged. Additionally, the problem of initial values, which are difficult to estimate for squat jumps and drop jumps, was addressed by suggesting a new method for the calculation of CG height of squat and drop jumps. To evaluate and compare the methods used to examine the vertical jump performance, 15 men performed four maximal vertical jumps of three different types: counter movement jump (CMJ), squat jump (SJ) and drop jump (DJ). Kinematic data and the vertical ground reaction force were recorded. Three methods were used for the evaluation of the jumps: flight time method (FT), impulse method based on the energy conservation law (IMP) and the double numerical integration of the ground reaction force (INT). The maximum CG height calculated from three-dimensional (3D) kinematics using automatic infrared (IR) marker tracking (Vicon [Oxford, UK], Plug in Gait model, Davis et al., 1991) was used as reference (golden standard). The results of the 3D kinematic analysis and the double integration of the vertical reaction force did not show significant differences. The jump heights determined by IMP and by FT were too low in relation to the real jump height due to the absence of the CG height at take off. Besides this, the flight time can be manipulated by the jumper, meaning that the flight time method is not suitable for CG height estimation of vertical jumps in scientific studies.

A Study of Center of Gravity in Different Phases of Selected Soccer Kicks

The center of gravity (CG) of the human body is a hypothetical point around which the force of gravity appears to act. CG need not lie within the physical bounds of an object. Human beings do not remain fixed in the anatomical position and the precise location of the CG changes constantly with every new position of the body and limbs. CG plays an important role in maintaining balance, equilibrium, and breaking inertia during the performance of a sports technique. Purpose of this study is to discover the pattern and make the comparison of CG height and CG velocity changes in the execution of frequently used soccer kicks within and between the kicks by the male players. Five male players played for the Bangladesh National Football teams were selected as subject and their age was between 16-19 years. A Cannon EOS7D with the capacity of 55 f/sec camera placed on sagittal plane at the backside of the kick 5.00 meters away and at 1.13 meter of height to capture kicking actions of the players on Coronal/Frontal plane. The best frame was selected out of 3 trials. 2D motion Analysis Software Kinovea 0.8.25 was employed for the quantitative analysis of the video clips. Changing of the CG height position in percentage was studied in three different phases i.e. Ground contact, Ball contact, and Follow-through in reference to erect standing CG height of the players. In addition, CG velocity changes were also studied in ball contact and follow-through phases. This study demonstrates that the male soccer players demonstrate inconsistency in CG height reduction in performing all three phases (Ground Contact, Ball Contact, & Follow-through) in all selected five kicks (Push Pass, Instep Kick, Lofted Kick, Chip Shot, and In-swerve Kick), but highest reductions have been located in the ball contact phase of all the kicks. Players change CG height in the same manner among the five selected kicks in each of the phases distinctly. Players experience CG height drop in Instep Kick differently between ball contact and ground contact phases. Players display higher mean CG velocity in ball contact phase than follow-through phase in Push Pass but remaining other kicks exhibit opposite actions. Players display CG velocity in all selected soccer kicks in the same manner at ball contact and follow-through phases. Players change CG velocity differently between Push Pass and Instep Kick, In-swerve Kick, Lofted Kick at follow-through phase.

Alpine Skiing Robot Using a Passive Turn with Variable Mechanism

Recently, the number of alpine ski junior players in Japan has drastically decreased. The causes include a decrease in ski areas and instructors, along with difficulty of early childhood alpine ski guidance. The alpine ski competition is not simply a glide on a slope. It requires understanding of ski deflection and skier posture mechanics. Therefore, a passive ski robot without an actuator was developed for junior racers of the alpine ski competition to facilitate understanding of the turn mechanism. Using this robot can elucidate factors affecting ski turns, such as the position of the center of gravity (COG) and the ski shape. Furthermore, a mechanism for changing the COG height, the edge angle and the ski deflection is added to the passive turn type ski robot. The developed ski robot can freely control the turn by changing those parameters during sliding.

The Rollover Risk in Delta Tricycles: A New Rollover Index and Its Robust Mitigation by Rear Differential Braking

Although there are efforts to electrify and diversify small vehicles, active safety on motorcycles and tricycles (also known as auto rickshaw, tuk-tuk, mototaxi, etc.) has been relegated until a few years ago. For instance, the electric tricycles (even the combustion ones) marketed today do not have an active safety system that prevents or mitigates the risk of rollover, despite how prone they are to such a situation. The concern for the increase in its marketing is latent and, unfortunately, there are very few related studies. In this article, we present the obtaining and validation of a new rollover index for tricycles demonstrating its effectiveness in predicting and detecting the risk, even statically, by means of a simple quantity. In addition, a controller for the mitigation of the risk of rollover is presented which, by means of a Lyapunov type analysis, it is shown to be robust to changes in parameters, such as the center of gravity height, using a polytopic representation of the system and a differential braking strategy on the rear wheels. Numerical simulations, including video simulation captures, of the operation of the rollover mitigation system using widely recognized commercial software, are also presented. This work can be extended to vehicles with a suspension system or for trikes without autocamber.

Application of paclobutrazol: a strategy for inducing lodging resistance of wheat through mediation of plant height, stem physical strength, and lignin biosynthesis.

Lodging is a major constraint contributing to poor grain yield and quality of wheat (Triticum aestivum L.) worldwide. The use of plant growth regulators is becoming a foremost agro-chemical approach for minimizing the risk of lodging in cereal crops. The present study was conducted to examine the effects of the paclobutrazol application on culm physical strength, lignin content, and lodging resistance of wheat. Wheat seeds were soaked in paclobutrazol at the concentrations of 0 (CK, as control), 200 (PB1), 300 (PB2), and 400 (PB3) mgL-1. Our results showed that paclobutrazol resulted in a dose-dependent decrease of plant height, internode length, and center of gravity height. Paclobutrazol treatments evidently increased the culm diameter, culm filling degree, and wall thickness of basal internodes, resulting in greater stalk-breaking strength and lodging resistance index (CLRI), where their maximum values were obtained with PB1 treatment. In addition, the activities of lignin-related enzymes were improved by paclobutrazol, particularly at low concentration, which increased the lignin accumulation of the basal internodes of wheat, subsequently improving the capability of stalk lodging resistance. Moreover, the correlation analysis revealed significant correlations between stem diameter, culm filling degree, and lignin with stalk bending strength and CLRI. The paclobutrazol concentration ≥ 300mgL-1 (PB2 and PB3 treatments) showed inhibitive effects on various culm morphological traits. These results suggest that not only the plant height, but also the lignin contents and physical strength of internodes are closely related with the lodging resistance of wheat, and reduction in plant height along with improved culm morphological characteristics and higher lignin accumulation in basal internodes could effectively relieve the risk of lodging.

Mepiquat chloride application increases lodging resistance of maize by enhancing stem physical strength and lignin biosynthesis

Lodging is a major adversity which limits maize grain yields and quality, especially under dense population. The present study was conducted to determine the efficacy of mepiquat chloride, a potential anti-gibberellic plant growth retardant on plant height, the physical strength of stem, lignin content and its relationship with lodging resistant in maize crop. Maize seeds were dressed with mepiquat chloride at the rate of 0 (MC0), 2.0 (MC1), 2.5 (MC2), and 3.0 (MC3) g kg−1 during 2015–2016. Our results showed that mepiquat chloride treatments enhanced the culm physical strength, as revealed by enhanced rind puncture strength and stalk bending strength, increased dry weight per cm, stem diameter, and lignin accumulation resulting in strong lodging resistance. A significant and negative correlation was detected between stalk bending and rind puncture strength with lodging rate. Moreover, the lodging rate, plant height, internodes length and gravity center height were significantly reduced following a dose-response trend, and MC2 and MC3 treatments resulted in relatively shorter plants, compared to control treatment. In addition, the grain yield, lignin contents and activities of lignin-related enzymes were enhanced by mepiquat chloride, and the MC2 (2.5 g kg−1) treatment showed the best effect of all treatments. The correlation analysis revealed that lignin accumulation was negatively and significantly correlated with lodging rate of the maize crop. Our results imply that plant height obviously, as well as the culm physical strength and lignin are closely associated with the lodging resistance in maize, and the decreased plant height, enhanced culm morphological characteristics and lignin content could strengthen the resistance of crops to lodging.

Muscular activity and acceleration of box vibration in manual holding tasks: effects of load and height of the load's center of gravity

This study recruited 14 participants to examine the effects of load and height of the load's center of gravity (COG) on muscular activities of the brachioradialis, biceps brachii and erector spinae, and on box vibration acceleration (g) in manual holding tasks. Each participant was asked to hold a box in 12 conditions (4 loads × 3 heights of the load's COG). The results showed that muscular activities of the brachioradialis, biceps brachii and erector spinae significantly increased with load; however, they were not affected by the height of the load's COG. In addition, box vibration acceleration increased with load, and decreased with the height of the load's COG. The interaction effect of load and height of the load's COG on box vibration acceleration was also significant. This study recommends that the load magnitude should be decreased for the holding task that requires low vibration.

Modeling the effect of liquid movement on the center of gravity calculation of agricultural vehicles

Due to a high center of gravity (CG) location, agricultural vehicles are more vulnerable to overturns. The CG location can be calculated using the lifting axle method of ISO 16231-2:2015. But, as a vehicle is lifted, its liquid payloads are not entirely contained. The liquids will shift both in position and form, affecting the CG height calculation.A mathematical model was developed to predict the effect of liquid movement on the CG height calculation of a tilted vehicle. The model was validated using an agricultural utility tractor and a prototype. The developed model was applied to calculate the CG location considering the effect of the liquid shift.Results showed tilting produced a higher calculated center of gravity due to liquid movement, but by increasing the tilting angle, the calculated CG height decreased. The effect of the liquid shift on CG height measurement for the wagon with 16.0% liquid mass was 14.8% and for the tractor with 1.2% liquid mass was 0.41%. The model error was less than 1.3% for all tests. Considering the effect of the liquid shift in CG height calculation, the error in CG height calculation decreased from 11.9% to 2.6% for the wagon.

Shading Contributes to the Reduction of Stem Mechanical Strength by Decreasing Cell Wall Synthesis in Japonica Rice (Oryza sativa L.).

Low solar radiation caused by industrial development and solar dimming has become a limitation in crop production in China. It is widely accepted that low solar radiation influences many aspects of plant development, including slender, weak stems and susceptibility to lodging. However, the underlying mechanisms are not well understood. To clarify how low solar radiation affects stem mechanical strength formation and lodging resistance, the japonica rice cultivars Wuyunjing23 (lodging-resistant) and W3668 (lodging-susceptible) were grown under field conditions with normal light (Control) and shading (the incident light was reduced by 60%) with a black nylon net. The yield and yield components, plant morphological characteristics, the stem mechanical strength, cell wall components, culm microstructure, gene expression correlated with cellulose and lignin biosynthesis were measured. The results showed that shading significantly reduced grain yield attributed to reduction of spikelets per panicles and grain weight. The stem-breaking strength decreased significantly under shading treatment; consequently, resulting in higher lodging index in rice plant in both varieties, as revealed by decreased by culm diameter, culm wall thickness and increased plant height, gravity center height. Compared with control, cell wall components including non-structural carbohydrate, sucrose, cellulose, and lignin reduced quite higher. With histochemical straining, shading largely reduced lignin deposition in the sclerenchyma cells and vascular bundle cells compared with control, and decreased cellulose deposition in the parenchyma cells of culm tissue in both Wuyunjing23 and W3668. And under shading condition, gene expression involved in secondary cell wall synthesis, OsPAL, OsCOMT, OsCCoAOMT, OsCCR, and OsCAD2, and primary cell wall synthesis, OsCesA1, OsCesA3, and OsCesA8 were decreased significantly. These results suggest that gene expression involved in the reduction of lignin and cellulose in both sclerenchyma and parenchyma cells, which attribute to lignin and cellulose in culm tissue and weak mechanical tissue, consequently, result in poor stem strength and higher lodging risks.Highlights:(1) Shading decreases the stem mechanical strength of japonica rice by decreasing non-structural carbohydrate, sucrose, lignin, and cellulose accumulation in culms.(2) The decrease of carbon source under shading condition is the cause for the lower lignin and cellulose accumulation in culm.(3) The expression of genes involved in lignin and primarily cell wall cellulose biosynthesis (OsCesA1, OsCesA3, and OsCesA8) at the stem formation stage are down-regulated under shading condition, inducing defective cell wall development and poor lodging resistance.

Global modeling and simulation of vehicle to analyze the inertial parameters effects

This paper mainly studies the comparison of the global vehicle models and the effects of the inertial parameters due to the center of gravity (CG) positions when we consider that the vehicle has only one CG. This paper proposes a new nonlinear model vehicle model which considers both unsprung mass and sprung mass CG. The CG positions and inertial parameters effects are analyzed in terms of the published vehicle dynamics models. To this end, two 14 degree-of-freedom (DOF) vehicle models are developed and compared to investigate the vehicle dynamics responses due to the different CG height and inertial parameters concepts. The proposed models describe simultaneously the vehicle motion in longitudinal, lateral and vertical directions as well as roll, pitch and yaw of the vehicle about corresponding axis. The passive and active moments and the forces acting on the vehicle are also described and they are considered as a direct consequence of acceleration, braking and steering maneuvers. The proposed model [Formula: see text] takes both the CG of sprung mass, unsprung mass and total vehicle mass into account. The second model [Formula: see text] assumes that the vehicle is one solid body which has a single CG as reported in majority of literature. The two vehicle models are compared and analyzed to evaluate vehicle ride and handling dynamic responses under braking/acceleration and cornering maneuvers. Simulation results show that the proposed model [Formula: see text] could offer analytically some abilities and driving performances, as well as improved roll and pitch in a very flexible manner compared to the second model [Formula: see text].

Estimation of Center of Gravity Position for Distributed Driving Electric Vehicles Based on Combined H∞-EKF Method

It is essential to get the accurate knowledge of the center of gravity (CG) for the vehicle dynamics control systems, especially for distributed driving electric vehicles (DDEV), whose CG positions can be affected by the loading conditions. This paper focuses on a CG position estimator for a DDEV based on the combined H∞—extended Kalman filter (H∞—EKF) approach. The designed estimator consists of two parts: an H∞ estimator is used for filtering noisy states and an EKF is employed for estimating parameters. The H∞ filter minimizes the effects of undesirable noise in the filtered states with the disturbances whose statistics are unknown. Meanwhile, the EKF uses the filtered states from the H∞ filter and takes the parameters as random walks. Simulation results show that the proposed filter is capable of estimating the CG longitudinal location and the CG height with acceptable accuracy.