Showing papers on "Rear-end collision published in 2015"

Development of a Deceleration-Based Surrogate Safety Measure for Rear-End Collision Risk

Abstract: A surrogate safety measure can be used for preventing hazardous roadway events by evaluating the potential safety risk by using information on the driving environment gathered from vehicles. In this paper, the deceleration-based surrogate safety measure (DSSM) is proposed as a safety indicator for rear-end collision risk evaluation based on the safety conditions and the decision-making process during human driving. The DSSM shows how drivers deal with collision risk differently in acceleration and deceleration phases. The proposed surrogate safety model has been validated for severe deceleration behavior, which is a driver-critical behavior in high-risk situations of collision based on microscopic vehicle trajectory data. The results indicate that there is a strong relationship between the proposed surrogate safety measures and crash potential. The measure could be used for collision warning and collision avoidance systems. It has a merit in that it reflects the characteristics of both vehicle (e.g., mechanical braking capability) and driver (e.g., preference for certain acceleration rates).

Autonomous rear-end collision avoidance using an electric power steering system

Abstract: A step towards fully autonomous vehicles can be achieved by autonomous collision avoidance. This paper presents the development and implementation of a rear-end collision avoidance system which consists of novel linear threat assessment, projected escape path planning with non-zero initial condition, reference generation and linear path control by an electric steering actuator using dynamic inversion. The linear threat assessment continuously calculates threat metrics associated with collision avoidance by either steering or braking. The escape path planner continuously estimates a path with constraints on the peak lateral acceleration and the required lateral deviation. The reference generator then estimates the states for avoidance according to the available friction. Linear state feedback control is applied for path following to avoid a collision in both straight-road scenarios and curved-road scenarios. The proposed approach is evaluated in simulations, and in practice on a C-segment Ford vehicle. A u...

Applying telecommunications methodology to road safety for rear-end collision avoidance

Abstract: This work aims at applying telecommunications methodologies to road safety for preventing rear-end collisions. This contribution can be considered as a pilot study to verify and assess the reliability of a new model and procedure for collision warning system based on low-cost inter-vehicular communications (only a cheap radio transmitter/receiver mounted on each vehicle is needed), where Global Positioning Systems (GPS) and other distance vector-based networks are not employed. A signal processing method, namely the binomial test, aimed at detecting approaching sources in infrastructure-less vehicular communications is here proposed and discussed. The detection probability of the method is evaluated versus several driving conditions, in terms of relative speeds and distances between vehicles. In addition, the Time To Collision (TTC), generally required before declaring a correct detection by existing collision systems implemented in recent vehicles, is evaluated for several driving scenarios characterized by different setting parameters. Our numerical results confirm the validity of such an approach in preventing rear-end collisions, allowing a fast detection of approaching sources.

Real-Time Lane Detection and Rear-End Collision Warning System on a Mobile Computing Platform

Abstract: Accident prevention systems have recently been a part of many modern cars to reduce injuries and casualties on the road. However, the high cost of components and equipment have limited such safety systems to higher-end and luxury vehicles. This paper proposes an economical method of using a smartphone application for real-time lane detection and rearend collision warning system for drivers on the road. The Android-based application uses image-processing algorithms coupled with the monoscopic camera on the smartphone as the main sensor to perform lane and vehicle detections. The novelty of this work lies in the use of the monocular vision of the camera to estimate the distance with the vehicle up ahead. The system is able to distinguish unintentional lane departure and if the driver is traveling too close to the vehicle ahead. An acoustic warning will notify the driver of a potential accident.

Automated Vehicle Response To Imminent Rear-End Collision

Abstract: A system for automated operation of a host-vehicle includes a vehicle-control device, an object-detection device, and a controller. The vehicle-control device is operable to control one or more of acceleration of the host-vehicle, braking of the host-vehicle, and steering of the host-vehicle. The object-detection device is operable to detect a rearward-vehicle located behind the host-vehicle. The controller is configured to determine when the object-detection device indicates that a rear-end collision into the host-vehicle by the rearward-vehicle is imminent, and operate the vehicle-control device to reduce the effect of the rear-end collision experienced by an operator of the host-vehicle when the rear-end collision is imminent.

A CAN protocol based embedded system to avoid rear-end collision of vehicles

Abstract: Driver and passenger safety is one of the prime concerns in modern day vehicle. Alarming statistics of accidents and increased number of vehicles on road demands for an intelligent safety mechanism that helps the driver in handling immediate precarious situations like sudden probability of a rear- end collision. The work proposes a mechanism that not only computes the deceleration of vehicle due to braking and displays the braking intensity through an array of LED but also involves monitoring the braking intensity levels and communicate it to the vehicles that are following it in lambertian range of IR transmitter module to avoid any collision pre-hand, due to any situation that may arise and cause immediate deceleration of the vehicle ahead. An ARM Cortex MO microcontroller will be interfaced with an accelerometer that senses the deceleration levels, a LED array to display the braking intensity and an IR transceiver module for inter-vehicle communication that would transmit pulses whose frequency is modulated proportional to the braking intensity level. To take decision and automatically control the motion of the following vehicle, a collision avoidance system consisting of CortexMO microcontroller is implemented that warns the drier using a buzzer and messages the active and passive safety mechanisms to be activated using CAN protocol and takes control decisions according to an algorithm designed to handle the situation.

Rear-end collision early warning method and system

Abstract: The invention, which belongs to the technical field of positioning, discloses a rear-end collision early warning method and system. The early warning method comprises: current position information and speed information of a vehicle are obtained; current position information and speed information of an adjacent vehicle are obtained; according to the current position information of the vehicle and the current position information of the adjacent vehicle, the distance between the two vehicles is calculated; on the basis of the current speed information of the vehicle and the current speed information of the adjacent vehicle, a rear-end collision safety distance is calculated; and according to the distance between the vehicle and the adjacent vehicle as well as the rear-end collision safety distance, whether the vehicle is at a rear-end collision risk is determined; if so, early warning information is outputted. With the method, early warning of possible rear-end collision occurrence can be carried out under the circumstances that no distance sensor for measuring the distances between two vehicles directly is used, so that the cost is lowered. The method and system can be applied to various road environments.

Genetic algorithm optimization-based vehicle rear-end collision fuzzy control method

Abstract: The invention discloses a genetic algorithm optimization-based vehicle rear-end collision fuzzy control method. The genetic algorithm optimization-based vehicle rear-end collision fuzzy control method is performed by a dual-input and single-output fuzzy controller. Relative distance error ds and relative speed error dv are selected to serve as input variables of the fuzzy controller, and accelerated speed Fad control amount which is actually output serves as an output variable. A genetic algorithm optimization fuzzy control rule is used, so that the performance of a vehicle control system is improved, the response speed is high, the avoidance of occurrence of a rear-end collision accident is facilitated, the energy consumption of a vehicle is reduced, and the control effect on collision avoidance is achieved.

Expressway all-weather rear-end collision prevention pre-warning method

Abstract: The invention provides an expressway all-weather rear-end collision prevention pre-warning method. The method comprises the arrangement of an internet instant communication system. The system comprises a mobile internet, a plurality of vehicle mounted mobile intelligent terminals, and a plurality of expressway monitoring center mounted intelligent terminals. Each vehicle mounted mobile intelligent terminal detects the travel data of the vehicle through a satellite positioning system in combination of an electronic map. In each monitoring center mounted intelligent terminal, a worker marks on the electronic map data of the center, and these data are transmitted to the system through the mobile internet. At the same time, the intelligent terminals also receive data emitted from other intelligent terminals of the system through the mobile internet and compare the data with data of the intelligent terminals. If the vehicle mounted mobile intelligent terminal detects that the vehicle has the likelihood of hitting a vehicle ahead or being hit by a vehicle behind, a voice warning can be made immediately to remind the driver to take early measures. When the monitoring center mounted intelligent terminal finds a vehicle traveling at an abnormal speed within its administrative territory, the worker in the monitoring center can actively inquire the driver of reasons by voice so as to prevent a rear-end accident.

Rear vehicle rear-end collision early warning device based on image recognition

Abstract: The utility model discloses a rear vehicle rear-end collision early warning device based on image recognition. The rear vehicle rear-end collision early warning device comprises a front vehicle body. An early warning device is installed at the tail of the front vehicle body and composed of a lamp driving circuit and an early warning indicator lamp, a camera shooting a front vehicle is installed in the front of the front vehicle body, and a vehicle-mounted terminal is connected to the output end of the camera. The vehicle-mounted terminal comprises a DSP chip module, a navigation system module, a speed measurement module, a display module and a center control module. The output end of the vehicle-mounted terminal is connected with the early warning device. According to the rear vehicle rear-end collision early warning device, movement of the front vehicle is recognized through the machine vision technology, so that intelligence is achieved, active safety protection can be carried out, possibly-caused injures are prevented in advance, the chain collision probability caused when rear-end collision happens is eliminated or lowered, the safety is greatly improved, collision accidents are prevented, and the rear vehicle rear-end collision early warning device has the advantages of being high in precision, wide in vision range and capable of effectively detecting obstacles and reducing the misinformation probability.

Protection method and device for rear-end collision

Abstract: The invention provides a protection method and device for rear-end collision. According to the method and device, the personal injury caused by rear-end collision can be reduced. The method comprises the steps that in the driving process of an automobile, through a radar, the following back distance is detected; whether the following back distance is smaller than the distance threshold value or not is judged, and if the following back distance is smaller than the distance threshold value, the collision time is calculated according to the following back approach speed and the following back distance; whether the collision time is smaller than the time threshold value or not is judged, and if the collision time is smaller than the time threshold value, an air bag arranged on an automobile rear bumper is detonated, and after the air bag is supported to be open, a strip-shaped inflation bag is formed on the outer side of the automobile rear bumper.

Research on Safety Distance Mathematical Model of Pro-Active Head Restraint in Rear-end Collision Avoidance System

Abstract: Pro-active head restraint is a new automotive safety device with both active safety and passive safety characteristics. It can make a pre-estimation of the occurrence possibility of rear-end collision. Thus, the whiplash injury can be effectively reduced or even prevented. One of the key elements in rear-end collision avoidance system is to establish an effective safety distance mathematical model. Based on the running state of front car, the related calculation models of safety distance are established by means of dynamical and kinematical analysis of vehicle braking process and following process. Taken randomness and dynamic characteristics of parameters into consideration, the fuzzy relations between these parameters should be validated by means of fuzzy theory. Thus, it may accord with the actual driving conditions. By using the MATLAB software, the study shows that safety distance model and the methods used to determine parameters are reasonable, and the false alarm can be effectively minimized.

Rear-end collision prevention image projection and display safety system and processing method thereof

Abstract: The invention provides a rear-end collision prevention image projection and display safety system. The rear-end collision prevention image projection and display safety system comprises a vehicle distance collecting device, a control terminal and a display device; the vehicle distance collecting device is in communication connection with the control terminal, the control terminal is in communication connection with the display device, and the display device comprises a projector and a projection curtain; and the projector is installed at a vehicle chair pillow of a rear seat of a car, the control terminal is in communication connection with the projector, the projection curtain is installed on a rear windshield, and the projector projects images to the projection curtain. A processing method of the rear-end collision prevention image projection and display safety system includes the step that after the vehicle distance between a vehicle and a vehicle behind the vehicle is collected, the real-time vehicle distance is projected to the rear windshield to remind the vehicle behind the vehicle to pay attention to safety traffic. The rear-end collision prevention image projection and display safety system and the processing method have the beneficial effects that the defects in a traditional rear-end collision prevention system OLED display screen are effectively avoided, and the defect that a rear-end collision prevention image display device is not human-friendly is overcome.

On the potential of accelerating an electrified lead vehicle to mitigate rear-end collisions

Abstract: This paper analyzes the potential safety benefit from autonomous acceleration of an electrified lead vehicle to mitigate or prevent being struck from behind. Safety benefit was estimated based on the expected reduction in relative velocity at impact in combination with injury risk curves. Potential issues and safety concerns with the operation and implementation of such a system in the real world are discussed from an engineering and human factors stand point. In particular, the effect of the pre-collision acceleration in reducing whiplash injury risk due to change in head posture and reduction of crash severity is also discussed. In general, this study found that autonomously accelerating an electrified lead vehicle can mitigate and prevent rear-end collisions and significantly increase the safety benefits from existing systems such as autonomous emergency braking.

Active emergency steering system and method for preventing vehicle rear-end collision

Abstract: An active emergency steering system for preventing vehicle rear-end collision comprises a first sensor component, a second sensor component, a third sensor component, a judgment unit and an execution unit. The judgment unit judges the collision time of an existing vehicle and a preceding vehicle and the steering time of the existing vehicle steering to the emergency steering direction according to the information of the first sensor component to the third sensor component, comparison between the collision time and the steering time is conducted, and the judgment unit makes the existing vehicle to steer actively and emergently according to a comparison result, so that the existing vehicle is avoided from being collided with the preceding vehicle. According to the active emergency steering system and method for preventing the vehicle rear-end collision, the conditions around the existing vehicle and the conditions of the existing vehicle itself can be automatically analyzed, when collision between the existing vehicle and the preceding vehicle can not be avoided through a brake of the existing vehicle, the system can assist a driver in reducing occurrence of rear-end accidents through steering, and therefore the safety performance of the vehicle is improved.

A model-based rear-end collision avoidance algorithm for heavy commercial road vehicles

Abstract: A rear-end collision is one of the most frequent accidents occurring on roadways. In this paper, a model-based longitudinal collision avoidance algorithm is developed for heavy commercial road vehi...

Modeling and Analysis of Train Rear-End Collision Accidents Based on Stochastic Petri Nets

Abstract: We proposed a model of the train rear-end collision accidents based on stochastic Petri nets (SPN) theory. By isomorphic Markov chain model of the proposed accident model, we provide the quantitative analysis of the train rear-end collision accidents. Fuzzy random method is also applied to analyze the performance of the proposed model. In addition, according to the data extracted from a large amount of historical data of the accident statistics, we present a case analysis and discussion. It showed that the results of the proposed train rear-end accident model based on SPN are reasonable in practical applications and can be used to effectively analyze the accidents and prevent loss, and the results may be a reference to the department of railway safety management.

Preceding vehicle rear-end collision prevention automatic alarm system and method for vehicle

Abstract: The invention relates to the field of vehicle active safety, in particular to a preceding vehicle rear-end collision prevention automatic alarm system for a vehicle The preceding vehicle rear-end collision prevention automatic alarm system for the vehicle comprises an accelerator pedal detection module, a vehicle-mounted computer and a vehicle brake lamp, wherein the vehicle-mounted computer is connected with the accelerator pedal detection module and the vehicle brake lamp; the detection module is used for detecting whether an accelerator pedal is completely released in real time after the vehicle is started; the vehicle-mounted computer is capable of controlling the vehicle brake lamp to give an alarm when the accelerator pedal is completely released Accordingly, the invention also provides a preceding vehicle rear-end collision prevention automatic alarm method for a vehicle According to the invention, after a user completely releases an accelerator, the brake lamp is controlled to give an alarm, the gap from releasing the accelerator to pedaling a brake pedal by the user is filled, a rear vehicle is timely informed of the condition that a preceding vehicle is slowed down, and is prompted to keep a safe driving distance, a certain response time is provided for the rear vehicle, the rear-end collision is effectively prevented, and the driving safety is improved Meanwhile, more worry-saving and convenient driving experience is also provided for the user

Rear-end collision preventing system and method

Abstract: The embodiment of the invention discloses a rear-end collision preventing system and method and belongs to the field of traffic safety protective devices The rear-end collision preventing system comprises a signal acquisition unit for acquiring the driving data information, relative to a rear vehicle, of a vehicle, a control unit, and an alarm unit for reminding the driver of the vehicle and warning the rear vehicle, wherein the signal acquisition unit and the alarm unit are connected with the control unit respectively The rear-end collision preventing system and method, provided by the invention, can monitor the driving data information, relative to the rear vehicle, of the vehicle in real time, judge that whether the distance from the rear vehicle to the vehicle can cause rear-end collision threat to the vehicle according to the driving data information, warn the driver of the vehicle and warning the rear vehicle according to the practical situation, and prevent the rear-end collision accident in a more intelligent and effective manner

Warning device used for avoiding rear-end collision again after car accident or car breakdown

Abstract: The invention relates to a warning device used for avoiding rear-end collision again after a car accident or a car breakdown. The warning device can be started manually after the car accident or the car breakdown and can be started automatically when the car accident happens. The warning device comprises a power source device, a wireless warning transmitting circuit, a wireless warning receiving circuit, a control circuit and the like. The warning device has the advantages that after the car accident or the car breakdown, the warning device can be started manually or automatically to transmit wireless warning signals to rear cars, and the rear cars can receive the wireless warning signals immediately and give alarms, so that the rear cars can be informed of the car accident or the car breakage in the front and can take relevant measures to avoid rear-end collision.

Device for reminding front and back vehicles for preventing rear-end collision on expressway

Abstract: The invention discloses a device for reminding front and back vehicles for preventing rear-end collision on an expressway. The device for reminding the front and back vehicles comprises a light ray sensing array, which is used for detecting space of a target vehicle; a camera group, which is used for collecting a light-shown slogan of a tail light of a front vehicle; a sensor group, which is used for detecting the monitoring scale of the camera group; a data processing module, which is used for receiving the image data of the space and slogan of the tail light of the front vehicle, and the data backup of monitoring scale, and then converting the image information, distance information and the monitoring scale data to voice data; a data sending module; a man-machine operation interface; a voice broadcasting module. Through detecting the space of the target vehicle by visible light, setting the indicated slogan of the tail light of the automobile, identifying the slogan of the tail light of the front vehicle by the camera group while converting the data to voice information to broadcast, the driving comfort level and safety are greatly improved, and the purpose of preventing the rear-end collision is realized; besides, the device can vividly and directly display the light-shown language so as to provide warning information of safe driving for a driver of the back vehicle.

Train control system and train provided with same

Abstract: When rail car units running in the same direction are undergoing controlled separation during travel and the brake device of the rear train is behaving abnormally when the forward train has carried out brake control, the rear car may not be able to sufficiently decelerate, leading to a rear end collision with the forward car. In the event of a rear end collision, if the relative speed between the forward car and the rear car is equal to or less than a certain value, the impact force caused by the collision is comparable to the impact occurring in normal coupling, which does not affect the safety of the passengers nor cause trouble in the cars. Therefore, it will be necessary to implement speed control such that even if the deceleration of the rear car is delayed due to the above factor, the relative speed at the time of the rear end collision will be less than the certain value. The present invention provides a railcar brake control method in which a forward car and a rear car are separated during travel, said railcar brake control method being characterized in that when the forward car and the rear car are separated, a determination is made as to whether or not the brake device of each car is behaving abnormally on the basis of information regarding brake generating force of the forward car or the rear car, and when there is no abnormality, the distance between the forward car and the rear car is made equal to or more than a predetermined distance.

Rear-end collision prevention bike tail lamp

Abstract: The utility model discloses a rear-end collision prevention bike tail lamp. The rear-end collision prevention bike tail lamp comprises a shell. A power source module, a single-chip microcomputer control module, an ultrasonic ranging sensor module, LED lamp modules and a buzzer are arranged inside the shell. The power source module is connected with the single-chip microcomputer control module and the ultrasonic ranging sensor module. The single-chip microcomputer control module is connected with the ultrasonic ranging sensor module, the LED lamp modules and the buzzer. When a cyclist rides a bike in an environment with dark surrounding light, the rear-end collision prevention bike tail lamp can remind a vehicle behind the cyclist to keep safe distance if the distance between the vehicle and the cyclist is too short, the rear-end collision prevention bike tail lamp also reminds the cyclist to pay attention to the vehicle behind, and therefore the occurrence probability of an accident is lowered.

Dynamic Rear-End Collision Mitigation for a Vehicle About to be Struck

Abstract: Increases in sensing and computing capability in modern vehicles create opportunities for improving safety through active control of the vehicle motion. A system for mitigating rear-end collisions is introduced, focusing on the strategies a vehicle about to be struck could employ to reduce the severity of the crash. Due to high differential speeds and tight space constraints, the timing and precision of control inputs are critical, preventing human drivers from effectively employing these strategies. However, the results of the study presented in this paper suggest that there are relatively unobtrusive strategies that a single vehicle with some limited autonomy could use in joining a roadway queue that would improve the safety of the occupants.Copyright © 2015 by ASME

Introduction of Traffic Situation Management for a Rigid Truck, Tests Conducted on Object Avoidance by Steering within Ego Lane

Abstract: Awareness in traffic situations and manoeuvring efficiently through complex scenarios is a critical task to be managed for active safety and autonomous vehicle applications. This task could be assigned as a separate functionality layer due to its complexity. A reference development framework for autonomous heavy vehicle applications called Traffic Situation Management functionality layer is presented in this study. This functionality layer is then verified by developing a real time autonomous rear end collision avoidance function by steering based on the reference framework. The motion of the truck is restricted within the existing lane, representing situations where there is a partial lateral interference by other vehicles, with safe distance to manoeuvre both in the longitudinal and lateral directions. Lane markings are used as a reference to guide the vehicle within the ego lane during the avoidance manoeuvre. Based on the traffic scenario and ego vehicle states an escape path is generated. A simple feed-forward and PD based feedback controller is used to track the generated path. Physical tests are conducted on a 6X2 rigid heavy truck to verify the proposed function. Results indicate satisfactory performance of the avoidance function and safe margins during the test runs.

Rear-end collision early-warning system and method based on visible light communication

Abstract: A rear-end collision early-warning system based on visible light communication, comprising a positioning module (4), an MCU (3), an optical communication modulation module (2), an LED lamp (1), a photosensitive receiver (5) and an HMI system (6). The positioning module (4), the optical communication modulation module (2), the photosensitive receiver (5) and the HMI system (6) are connected to the MCU (3) separately, and the LED lamp (1) is connected to the optical communication modulation module (2). Also disclosed is a rear-end collision early-warning method based on visible light communication. Rear-end collision early-warning systems based on visible light communication are mounted on a front vehicle (7) and a rear approaching vehicle (8) respectively, the rear approaching vehicle (8) sends information to the front vehicle (7) in an active manner, such that the front vehicle (7) can obtain more state information about the rear approaching vehicle (8), thereby ensuring the accuracy in rear-end collision early warning of the front vehicle (7). In addition, an appropriate TTC threshold can be selected for the rear-end collision early warning of the front vehicle (7) according to a vehicle model of the rear approaching vehicle (8), thereby making judgment more accurate.

An Intelligent Embedded Diagnostic System on CAN Protocol to Avoid Rear-End Collision of Vehicles

Abstract: Background/Objectives: In a modern day vehicle, the safety of drivers and passengers are of utmost significance. With increase of traffic on roads, there are increased cases of accidents and mishaps which call for a robust driver and passenger assisting systems that can overcome and handle these situations effectively. Methods/Statistical Analysis: The work proposes an intelligent embedded system that assists the driver in avoiding a rear end collision with its on board diagnostics. It is a mechanism that monitors the braking intensity of vehicle and depending upon its intensity alerts the other vehicles that are immediately following. The device on the following vehicle immediately is activated to take decisions to avoid the impending collision. An accelerometer interfaced to ARM Cortex M0 microcontroller is a part of the transmitter devices that calculates the rate of deceleration and notifies the device on following vehicle by displaying it on the rear LED arrays and transmitting messages through IR communication. The receiver device is responsible to decode the message and follow a control algorithm based on many other parameters to either decelerate or stop the vehicle notifying the driver immediately. The system also hosts an on board Diagnostic system over CAN protocol that assists the driver and the repair technician during servicing, thus reducing the debugging effort and facilitating easy. Findings: Literature survey states road accidents are very common in India due to human errors. Existing system are becoming advanced and they reached up to tracking the traffic by using GPS to avoid accidents. Various traffic managements systems are being developed. Proposed work introduces a new system which tells the intensity of braking in car, to the nearby cars in order to keep the driver alert, which helps in avoiding the accidents. Conclusion/Improvements: The proposed system has advantages over the other existing system in terms of response time and independency on external infrastructure. It is also cheap in terms of cost and reliable when tested in actual environment. The system does not intend to notify other running vehicles except the ones that are following it or is in the lambert Ian line of sight of the array of IR transmitter lined in the rear bumper. Hence it effectively helps in reducing the accidents due to human errors by alerting the driver in advance.

Vehicle body frame structure

Abstract: PROBLEM TO BE SOLVED: To provide a vehicle body frame structure which inhibits an engine from moving forward thereby protecting a crew compartment, etc. during a vehicle rear end collision in a rear engine type or mid engine type vehicle.SOLUTION: A vehicle frame structure 1 includes: a rear cross member 16 which is disposed along a vehicle width direction at the rear side of a vehicle cabin; rear side frames 17 which are disposed along a vehicle fore and aft direction at both sides when viewed in a vehicle width direction and connected with end parts of the rear cross member 16; and reinforcement frames 20, each of which is spanned between the rear cross member 16 and the rear side frame 17.