Intelligent Tire Based Pressure Monitoring Algorithm

Author(s):  
Seyedmeysam Khaleghian ◽  
Saied Taheri

Intelligent tire is a relatively new technology that provides useful tire-road contact information by directly monitoring the interaction between the tire and the road. Different types of sensors are attached to the tire inner-liner for this purpose; the sensor data then will be used to estimate the tire-road contact parameters as well as to monitor the tire conditions. In this study, a tri-axial accelerometer was used and a two-steps intelligent tire based pressure monitoring algorithm was developed in this study. First, the angular velocity of the wheel was estimated based on the parameters extracted from the acceleration components through a trained neural network. Then the estimated wheel angular velocity from the first step was used along with the acceleration components to estimate the power of radial acceleration. The estimated power was compared to the actual one and the tire pressure condition was judged to be “normal” or “low”. To train the neural networks, the experimental data collected using an instrumented vehicle was used. A VW Jetta 2003 was used for this purpose and instrumented with appropriate sensors; intelligent tires, steering wheel sensor to measure the steering angle, steering velocity and steering torque, encoders to measure the angular speed of the wheels and an Inertial Measurement Unit (IMU) to measure the vehicle linear and angular acceleration. Another set of experimental data with different tire pressures and different vehicle velocity was then used to validate the algorithm; good agreements were observed between the estimated tire pressures and the actual ones.

Author(s):  
Vicky Mudeng ◽  
Barokatun Hassanah ◽  
Yun Tonce Kusuma Priyanto ◽  
Okcy Saputra ◽  
◽  
...  

Mobile transportation robots using two wheels have now been investigated. The work within this study is to design and simulate two-wheeled robots, thus it can maintain its balance. Many control methods are used to determine satisfactory control optimization, therefore a proper response is obtained by sensor recitation corresponding with the reaction of a Direct Current (DC) motor. Recently, two-wheeled transportation robot is a Segway model. In this study, we apply a Proportional Integral Derivative (PID) controller as a control system in a self-balancing robot with a working principle is similar to an inverted pendulum. In the next study, the PID controller and the whole system are applied in the microcontroller board. The angular velocity of two DC motors used as a plant can be adjusted by Pulse Width Modulation (PWM) through a motor driver. An Inertial Measurement Unit (IMU) sensor is utilized to detect the angular acceleration and angular velocity of the self-balancing robot. The phase design is constructed by planning the robot dimension, mechanical system, and an electronic system. Particularly, this study performs mathematical modeling of the robot system to obtain the transfer function. In addition, we simulate the PID parameter with multiplication between the basic parameter and several fixed constants. The simulation results indicate that the robot can maintain its balance and remains perpendicularly stable for balancing itself.


Sensors ◽  
2020 ◽  
Vol 20 (18) ◽  
pp. 5197
Author(s):  
Beomjun Kim ◽  
Yunju Baek

Advances in vehicle technology have resulted in the development of vehicles equipped with sensors to acquire standardized information such as engine speed and vehicle speed from the in-vehicle controller area network (CAN) system. However, there are challenges in acquiring proprietary information from CAN frames, such as the brake pedal and steering wheel operation, which are essential for driver behavior analysis. Such information extraction requires electronic control unit identifier analysis and accompanying data interpretation. In this paper, we present a system for the automatic extraction of proprietary in-vehicle information using sensor data correlated with the desired information. First, the proposed system estimates the vehicle’s driving status through threshold-, random forest-, and long short-term memory-based techniques using inertial measurement unit and global positioning system values. Then, the system segments in-vehicle CAN frames using the estimation and evaluates each segment with our scoring method to select suitable candidates by examining the similarity between each candidate and its estimation through the suggested distance matching technique. We conduct comprehensive experiments of the proposed system using real vehicles in an urban environment. Performance evaluation shows that the estimation accuracy of the driving condition is 84.20%, and the extraction accuracy of the in-vehicle information is 82.31%, which implies that the presented approaches are quite feasible for automatic extraction of proprietary in-vehicle information.


Author(s):  
Qingya Wu ◽  
Qingzhong Jia ◽  
Jiayuan Shan ◽  
Xiuyun Meng

A novel inertial measurement unit scheme with five accelerometers and two gyros (5A2G) is proposed in this paper to achieve high precision measurement in high dynamic environment. The three channels are decoupled during the angular velocity calculation procedure to ensure the precision and efficiency. The yawing and pitching angular velocities are directly measured by gyros, while only the rolling angular velocity is inferred indirectly from the rolling angular information vector composed of rolling angular acceleration and quadratic component of rolling angular velocity. Based on the proposed scheme, the configuration ascertainment problem for acquiring the required installation parameters of accelerometers is transformed into a constraint optimization problem with the objective of minimizing the error of rolling angular information vector. A single channel rolling angular velocity calculation model is then established on the basis of the optimal configuration and the extended Kalman filter algorithm is utilized for state estimation. Simulations are implemented and results indicate that the optimal 5A2G scheme is feasible for high-speed rotating ammunition.


2021 ◽  
Vol 14 (1) ◽  
pp. 126
Author(s):  
Fan Yang ◽  
Lei Liang ◽  
Changqing Wang ◽  
Zhicai Luo

The satellite gravity mission GRACE(-FO) has not yet reached its designed baseline accuracy. Previous studies demonstrated that the deficiency in the sensor system or the related signal processing might be responsible, which in turn motivates us to keep revising the sensor data processing, typically the spacecraft’s attitude. Many efforts in the past have been made to enhance the attitude modeling for GRACE, for instance, the latest release reprocesses the attitude by fusing the angular acceleration with the star camera/tracker (SC) measurements, which helps to reduce the error in Level-2 temporal gravity fields. Therefore, in addition to GRACE, revising GRACE-FO attitude determination might make sense as well. This study starts with the most original raw GRACE-FO Level-1A data including those from three SCs and one IMU (Inertial Measurement Unit) sensors, and manage to generate a new publicly available Level-1B attitude product called HUGG-01 covering from June 2018 to December 2020, using our independently-developed software. The detailed treatment of individual payload is present in this study, and an indirect Kalman filter method is introduced to fuse the multiple sensors to acquire a relatively stable and precise attitude estimation. Unlike the direct SC combination method with a predefined weight as recommended in previous work, we propose an involvement of each SC measurement in the Kalman filter to enable a dynamic weight adjustment. Intensive experiments are further carried out to assess the HUGG-01, which demonstrate that the error level of HUGG-01 is entirely within the design requirement, i.e., the resulting KBR pointing variations are well controlled within 1 mrad (pitch), 5 mrad (roll) and 1 mrad (yaw). Moreover, comparisons with the official JPL-V04 attitude product demonstrate an equivalent performance in the low-to-middle spectrum, with even a slightly lower noise level (in the high spectrum) than JPL-V04. Further analysis on KBR range-rate residuals and gravity recovery on Jan 2019 indicates that, i.e., RMS of the difference (HUGG-01 minus JPL-V04) for the range rate is less than 3.234×10−8 m/s, and the amplitude of geoid height difference is approximately 0.5 cm. Both differences are below the sensitivity of the state-of-the-art satellite gravity mission, demonstrating a good agreement between HUGG-01 and JPL-V04.


Author(s):  
Farid K. Moghadam ◽  
Amir R. Nejad

Abstract Drivetrain bearings are seen as the most common reason of the wind turbine drivetrain system failures and the consequent downtimes. In this study, the angular velocity error function is used for the condition monitoring of the bearings and gears in the wind turbine drivetrain. This approach benefits from using the sensor data and the dedicated communication network which already exist in the turbine for performance monitoring purposes. Minor required modification includes an additional moderate sampling frequency encoder without any need of adding an extra condition monitoring system. The additional encoder is placed on the low speed shaft and can also be used as the backup for the high speed shaft encoder which is critical for turbine control purposes. A theory based on the variations of the energy of response around the defect frequency is suggested to detect abnormalities in the drivetrain operation. The proposed angular velocity based method is compared with the classical vibration-based detection approach based on axial/radial acceleration data, for the faults initiated by different types of excitation sources. The method is experimentally evaluated using the data obtained from the encoders and vibration sensors of an operational wind turbine.


Author(s):  
Bryan R Cobb ◽  
Abigail M Tyson ◽  
Steven Rowson

This study sought to evaluate the suitability of angular rate sensors for quantifying angular acceleration in helmeted headform impacts. A helmeted Hybrid III headform, instrumented with a 3-2-2-2 nine accelerometer array and angular rate sensors, was impacted (n = 90) at six locations and three velocities (3.1, 4.9, and 6.4 m/s). Data were low-pass filtered using Butterworth four-pole phaseless digital filters which conform to the specifications described in the Society of Automotive Engineers J211 standard on instrumentation for impact tests. Nine accelerometer array data were filtered using channel frequency class 180, which corresponds to a −3 db cutoff frequency of 300 Hz. Angular rate sensor data were filtered using channel frequency class values ranging from 5 to 1000 Hz in increments of 5 Hz, which correspond to −3 db cutoff frequencies of 8 to 1650 Hz. Root-mean-square differences in peak angular acceleration between the two instrumentation schemes were assessed for each channel frequency class value. Filtering angular rate sensor data with channel frequency class values between 120 and 205 all produced mean differences within ±5%. The minimum root-mean-square difference of 297 rad/s2 was found when the angular rate sensor data were filtered using channel frequency class 175. This filter specification resulted in a mean difference of 28 ± 297 rad/s2 (1.8% ± 8.6%). Condition-specific differences (α=0.05) were observed for 11 of 18 test conditions. A total of 4 of those 11 conditions were within ±5%, and 10 were within ±10%. Furthermore, the nine accelerometer array and angular rate sensor methods demonstrated similar levels of repeatability. These data suggest that angular rate sensor may be an appropriate alternative to the nine accelerometer array for measuring angular head acceleration in helmeted head impact tests with impactor velocities of 3.1–6.4 m/s and impact durations of approximately 10 ms.


1975 ◽  
Vol 42 (3) ◽  
pp. 552-556 ◽  
Author(s):  
A. J. Padgaonkar ◽  
K. W. Krieger ◽  
A. I. King

The computation of angular acceleration of a rigid body from measured linear accelerations is a simple procedure, based on well-known kinematic principles. It can be shown that, in theory, a minimum of six linear accelerometers are required for a complete definition of the kinematics of a rigid body. However, recent attempts in impact biomechanics to determine general three-dimensional motion of body segments were unsuccessful when only six accelerometers were used. This paper demonstrates the cause for this inconsistency between theory and practice and specifies the conditions under which the method fails. In addition, an alternate method based on a special nine-accelerometer configuration is proposed. The stability and superiority of this approach are shown by the use of hypothetical as well as experimental data.


2001 ◽  
Vol 204 (3) ◽  
pp. 471-486 ◽  
Author(s):  
N. Copp ◽  
M. Jamon

The kinematic patterns of defense turning behavior in freely behaving specimens of the crayfish Procambarus clarkii were investigated with the aid of a video-analysis system. Movements of the body and all pereiopods, except the chelipeds, were analyzed. Because this behavior approximates to a rotation in place, this analysis extends previous studies on straight and curve walking in crustaceans. Specimens of P. clarkii responded to a tactile stimulus on a walking leg by turning accurately to face the source of the stimulation. Angular velocity profiles of the movement of the animal's carapace suggest that defense turn responses are executed in two phases: an initial stereotyped phase, in which the body twists on its legs and undergoes a rapid angular acceleration, followed by a more erratic phase of generally decreasing angular velocity that leads to the final orientation. Comparisons of contralateral members of each pair of legs reveal that defense turns are affected by changes in step geometry, rather than by changes in the timing parameters of leg motion, although inner legs 3 and 4 tend to take more steps than their outer counterparts during the course of a response. During the initial phase, outer legs 3 and 4 exhibit larger stance amplitudes than their inner partners, and all the outer legs produce larger stance amplitudes than their inner counterparts during the second stage of the response. Also, the net vectors of the initial stances, particularly, are angled with respect to the body, with the power strokes of the inner legs produced during promotion and those of the outer legs produced during remotion. Unlike straight and curve walking in the crayfish, there is no discernible pattern of contralateral leg coordination during defense turns. Similarities and differences between defense turns and curve walking are discussed. It is apparent that rotation in place, as in defense turns, is not a simple variation on straight or curve walking but a distinct locomotor pattern.


Author(s):  
Derek Nevins ◽  
Kasee Hildenbrand ◽  
Jeff Kensrud ◽  
Anita Vasavada ◽  
Lloyd Smith

Head impact sensors are increasingly used to quantify the frequency and magnitude of head impacts in sports. A dearth of information exists regarding head impact in un-helmeted sport, despite the substantial number of concussions experienced in these sports. This study evaluated the performance of one small form factor head impact sensor in both laboratory and field environments. In laboratory tests, sensor performance was assessed using a Hybrid III headform and neck. The headform assembly was mounted on a low-friction sled and impacted with three sports balls over a range of velocities (10–31 m/s) at two locations and from three directions. Measures of linear and angular acceleration obtained from the small form factor wireless sensor were compared to measures of linear and angular acceleration obtained by wired sensors mounted at the headform center of mass. Accuracy of the sensor varied inversely with impact magnitude, with relative differences across test conditions ranging from 0.1% to 266.0% for peak linear acceleration and 4.7% to 94.6% for peak angular acceleration when compared to a wired reference system. In the field evaluation, eight male high school soccer players were instrumented with the head impact sensor in seven games. Video of the games was synchronized with sensor data and reviewed to determine the number of false positive and false negative head acceleration event classifications. Of the 98 events classified as valid by the sensor, 20.5% (20 impacts) did not result from contact with the ball, another player, the ground or player motion and were therefore considered false positives. Video review of events classified as invalid or spurious by the sensor found 77.8% (14 of 18 impacts) to be due to contact with the ball, another player or player motion and were considered false negatives.


Author(s):  
S. Maier ◽  
T. Gostner ◽  
F. van de Camp ◽  
A. H. Hoppe

Abstract. In many fields today, it is necessary that a team has to do operational planning for a precise geographical location. Examples for this are staff work, the preparation of surveillance tasks at major events or state visits and sensor deployment planning for military and civil reconnaissance. For these purposes, Fraunhofer IOSB is developing the Digital Map Table (DigLT). When making important decisions, it is often helpful or even necessary to assess a situation on site. An augmented reality (AR) solution could be useful for this assessment. For the visualization of markers at specific geographical coordinates in augmented reality, a smartphone has to be aware of its position relative to the world. It is using the sensor data of the camera and inertial measurement unit (IMU) for AR while determining its absolute location and direction with the Global Navigation Satellite System (GNSS) and its magnetic compass. To validate the positional accuracy of AR markers, we investigated the current state of the art and existing solutions. A prototype application has been developed and connected to the DigLT. With this application, it is possible to place markers at geographical coordinates that will show up at the correct location in augmented reality at anyplace in the world. Additionally, a function was implemented that lets the user select a point from the environment in augmented reality, whose geographical coordinates are sent to the DigLT. The accuracy and practicality of the placement of markers were examined using geodetic reference points. As a result, we can conclude that it is possible to mark larger objects like a car or a house, but the accuracy mainly depends on the internal compass, which causes a rotational error that increases with the distance to the target.


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