KR20140024595A - Operation reliability improving method of smart parking assist system - Google Patents

Abstract

The present invention relates to a method for improving the reliability of operating an automatic parking assist system. The method comprises the following steps: 1) obtaining information necessary for calculating a wheel speed (S100); 2) verifying check value and sequence number about the information necessary for calculating the wheel speed after the first step (S200); and 3) performing a first validity check after the second step (S300). The reliable wheel speed is obtained by the present invention and the invention prevents electric power steering (EPS) from suddenly operating and vibrating, in advance, using the wheel speed. [Reference numerals] (AA) Start; (BB,DD) Dissatisfaction; (CC,EE) Satisfaction; (FF) End; (S100) Obtaining information necessary for calculating a wheel speed; (S1000) Providing the information of the non-operation of the automatic parking assist system; (S200) Varifying check value and sequence number about the information necessary for calculating the wheel speed; (S300) Primary validity check; (S400) Confirming the check value and sequence number via calculation; (S500) Secondary validity check; (S600) Third validity check; (S610) Calculating the wheel speed; (S620) Obtaining the wheel speed vehicle speed received from a CAN; (S630) [Wheel speed - vehicle speed] > 2KPH; (S700) Using the calculated wheel speed; (S800) Providing valid information capable of the parking assist system; (S900) Process without calculating the wheel speed

Description

Operation Reliability Improving Method of Smart Parking Assist System

The present invention relates to a wheel speed calculation method for improving operation reliability of Electronic Power Steering (EPS) when using an automatic parking assist system.

Currently, when a driver uses an automatic parking assistance system, information that enables the driver to be turned on / off uses the vehicle speed sent from the engine and the wheel speed sent from an electric stability control (ESC).

When the driver operates the automatic parking assistance system and parks the vehicle using the axel and the brake, the automatic parking assistance system does not operate when the vehicle speed increases beyond the prescribed range.

These vehicle speeds used in the automatic parking assistance system can satisfy the Automotive Safety Integrity Level (ASIL) D because only the vehicle speed itself is sent to the CAN (Controller Area Network) without the check-sum of the vehicle speed. none.

For reference, the vehicle speed sent from the engine through the current CAN signal and the wheel speed sent from the electronic safety control unit (ESC) satisfy the automotive safety integrity level (ASIL) B.

However, such a conventional automatic parking assistance system may introduce noise into a vehicle speed emitted by the CAN signal, or electromagnetic waves may flow into a CAN line, thereby distorting the vehicle speed.

In addition, when using the wheels that have not been validated, a problem occurs in which the automatic parking assistance system is temporarily deactivated by the wrong wheels or the driver feels the instantaneous starting and vibration of the electronic power steering (EPS).

When the vehicle is recognized at a low speed due to the inflow of electromagnetic waves and noise while driving at a high speed, and the parking assistance system is operated, a self-steer that operates the steering wheel automatically while the vehicle is at high speed is operated. There is a problem that a big accident can occur.

In addition, since these vehicle speeds and wheel speeds currently received from CAN do not have a check-sum, it is unreliable that the vehicle speeds and wheel speeds are valid values, and the regulation and the Automobile Safety Integrity Level (ASIL) D proposed by ISO26262 also apply. There is a problem that cannot be satisfied.

The technical problem to be achieved by the present invention is to provide a method of improving the operation reliability of the automatic parking assistance system that can be checked in the valid speed (Check-sum) in the vehicle speed and wheel received from the can (CAN) to a valid value will be.

The present invention provides a check value and a sequence number for a first step (S100), which is a process of acquiring information necessary for calculating the wheel speed, and information necessary for calculating the wheel speed, which is performed after the first step (S100). Auto parking, comprising a second step (S200), which is a process of checking a sequence number), and a third step (S300), which is a first validation process performed after the second step (S200). Provides a method for improving operational reliability of the auxiliary system.

In addition, the present invention proceeds when the first validity is satisfied in the third step (S300), and the fourth step (S400) and the fourth step (S400), which is a process of confirming a check value and a sequence number through calculation. It further comprises a fifth step (S500) that is a secondary validation process that proceeds after rough.

The present invention proceeds when the second validity of the fifth step (S500) is satisfied, and proceeds after the sixth step (S610) and the sixth step (S610), which is a wheel speed calculation process. The reference value represents the absolute value of the difference between the wheel speed and the vehicle speed that proceeds after the sixth step (S620) and the sixth step (S620) of acquiring the vehicle speed received from the calculated wheel speed and the CAN. It further comprises a sixth step (S600) is a third validation process including a sixth step (S630) that is a process of determining whether or not exceeding 2KPH (Kilo per Hour).

According to the present invention, the 6th-1-1 step (S611) and the 6-1-1 step (S611) are the process of acquiring the current and previous pulse counts. 6-1-2 which is a process of calculating the distance that is progressed after passing through 6-1-2 step S612 and 6-1-2 step S612, which is a process of counting the pulse change amount that proceeds after It comprises a step S613.

In the present invention, the wheel speed calculation process of step 6-1 (S610) is a process of acquiring the current and previous time stamps that are performed after the step 6-1-3 (S613). S614), a 6-1-5 step (S615) which is a process of counting the amount of change of the timestamp that proceeds after the 6-1-4 step (S614), and the 6-1-5 step ( Step 6-1, which is a process of calculating the time that proceeds after passing through S615) step 6-1-6 (S616) and step 6-1-6 (S616), wherein the wheel speed that proceeds after It further comprises -7 step (S617).

In the present invention, the process of acquiring the information necessary for calculating the wheel speed includes a wheel pulse count, a total number of pulses connected to a wheel of the vehicle, a circumferential length of the wheel, Timestamp Count and Timestamp Resolution are obtained.

Through the present invention, it is possible to make reliable wheels, and the use of such wheels produces an effect of preventing instantaneous oscillation and vibration of the electronic power steering (EPS).

In addition, it is possible to block the root cause of the occurrence of the self-steer described as a problem of the prior art, thereby enhancing the safety aspect of the driver, and the electronic power steering (when using the automatic parking assistance system). The operating reliability of EPS) can also be improved.

In addition, the effect of satisfying the Automobile Safety Integrity Level (ASIL) D as defined in ISO26262 is generated.

1 is a flow chart showing a method of improving operation reliability of the automatic parking assist system.
2 is a flow chart calculation.

Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings. In the drawings, the same reference numerals are used to designate the same or similar components throughout the drawings. In the following description of the present invention, a detailed description of known functions and configurations incorporated herein will be omitted when it may make the subject matter of the present invention rather unclear.

1 is a flowchart illustrating a method of improving operation reliability of an automatic parking assist system, and FIG. 2 is a flowchart in a wheel calculation.

The method of improving the operation reliability of the present invention, the automatic parking assistance system is required for the wheel speed calculation after the first step (S100) and the first step (S100), which is a process of acquiring the information necessary for the calculation of the wheel speed through a start step. A second step (S200), which is a process of checking a check value and a sequence number of information, and a third step, which is a first validation process performed after the second step (S200) (S300) and the fourth step (S400) and the fourth step (S400) which is a process of checking the check value and the sequence number through the calculation that proceeds when the first validity is satisfied in the third step (S300) A fifth step (S500) which is a second validation process performed after rough processing, a sixth step (S600) which is a third validation process performed when the second validity is satisfied in the fifth step (S500), In the sixth step S600, the third degree of validity is satisfied. The seventh step (S700), which is a process of using the calculated wheel speed, which is carried out at the right, and the eighth step (S800), which is a process of providing valid information for operating the parking assistance system, which is performed after the seventh step (S700). ), And does not calculate the wheel speed that proceeds when any one of the first validity of the third step (S300), the second validity of the fifth step (S500) or the third validity of the sixth step (S600) is dissatisfied. It includes a ninth step (S900) that is not a process and a tenth step (S1000) and the end step of providing a non-operational information of the automatic parking assist system that proceeds after the ninth step (S900).

In the process of acquiring the information required for calculating the wheel speed, which is the first step (S100), five pieces of information presented below are acquired to calculate the wheel speed, and the electronic safety control unit (ESC) can store the five pieces of information. Send it to the automatic parking assistance system through the communication line.

The five pieces of information are: 1. Wheel Pulse Count, 2. Total number of pulses connected to the wheel of the vehicle, 3. The circumferential length of the wheel, 4. Timestamp Count and 5. Timestamp Resolution.

The wheel pulse count is a number that increases when the sensor recognizes a pulse change according to the rotation of the wheel, and the timestamp count recognizes an increase in the pulse and indicates time count information thereof. The timestamp resolution indicates time information on an interval of timestamp counts.

The five pieces of information can be used to calculate the wheel speed during the third validation process, and when the electronic safety control unit (ESC) sends this information to the CAN, it checks whether the information is valid or not. ) And Sequence Number.

The second step (S200) is a process of checking the five pieces of information, check value, and sequence number, and in this process, the five pieces of information necessary for calculating the wheel speed in the electronic safety controller (ESC) and It also provides check values and sequence numbers, enabling primary validation of information exported to CAN.

The check value represents a value for the five pieces of information, and the sequence number is a number representing the order in which the information is delivered.

In the third step (S300), the first validation checks the check value and the sequence number. When noise and electromagnetic waves flow into the CAN line, the information and check value required to calculate the wheel speed are calculated. And since the sequence number is distorted together, it is possible to determine the validity of the information by confirming the expected check value and sequence number.

For example, among the values for the five pieces of information, 2. the total number of pulses connected to the wheel of the vehicle, 3. the circumference of the wheel, and 5. the timestamp resolution Since it is always a constant value in the same vehicle, it is a way to check this.

On the other hand, the fourth step (S400) that proceeds when the first validity is satisfied in the third step (S300) receives the information that has been validated first, and whether the check value and the sequence number is a valid value once again This is the process of checking through calculation.

That is, it is a process of checking whether the check values representing the values of the five pieces of information are in a valid range by checking whether the sequence numbers are sequentially transmitted.

If the information obtained through the calculation in the fourth step (S400) is confirmed as valid information through the second validation, which is the fifth step (S500), the third validation is performed, which is the sixth step (S600).

The sixth step (S600) is to obtain the calculated wheel speed and the vehicle speed received from the can (CAN) after the 6-1 step (S610) that is the wheel speed calculation process and the 6-1 step (S610). The absolute value of the difference between the wheel speed and the vehicle speed after the sixth step (S620) and the sixth step (S620) exceeds 2KPH (Kilo per Hour), which is a reference value indicating two kilometers per hour. And a step 6630 (S630), which is a process of determining whether it is.

The wheel speed calculation process in step 6-610 (S610) requires the five pieces of information, and step 6-1-1 (S611) in which the current and previous pulse counts are acquired through the start-up step as shown in FIG. ), And the 6-1-2 step (S612) and the 6-1-2 step (S612) that is a process of counting the pulse change amount that proceeds after passing through the 6-1-1 step (S611) 6-1-3 (S613), which is a process of calculating a distance, which is performed later, and 6-1-3, which is a process of acquiring current and previous time stamps that are performed after the 6-1-3 (S613). Step 6-1-5 (S615), which is a process of counting a change amount of the timestamp that proceeds after the fourth step S614 and the 6-1-4 step S614, and the six-1--1- Step 6-1-6 (S616), which is a process of calculating the time that proceeds after the fifth step (S615), and Process of calculating the wheel speed that proceeds after the step 6-1-6 (S616), 6-1-7 step S617, phase After the 6-1-7 step (S618) and the 6-1-8 step (S618), which is a process of changing the unit of the wheel that proceeds after the 6-1-7 step (S617) It includes a termination process.

In the 6-1-1 step (S611), the process of acquiring the current and previous pulse counts is a process of acquiring the number of the current pulse and the previous pulse since the pulses are numbered for each pulse formed around the wheel.

The 6-1-2 step S612 is a process of obtaining a pulse count by minus a previous pulse from a current pulse.

In the process of calculating the distance in the 6-1-3 step (S613), the pulse change amount obtained in the 6-1-2 step (S612) is divided by the total number of pulses, and the circumferential length of the wheel (unit: mm) is again obtained. The process of multiplying.

In terms of the equation,

Distance = pulse change * (1 / pulse total) * wheel circumference

to be.

The process of acquiring the current and previous time stamps in the 6-1-4 step S614 is a process of acquiring a time stamp in the current pulse and a time stamp in the previous pulse.

The process of counting the change amount of the time stamp in step 6-1-5 (S615) is a process of obtaining a value by minus the previous time stamp from the current time stamp.

The process of calculating the time in step 6-1-6 (S616) is a process of multiplying the timestamp resolution (unit: usec) by the amount of time stamp change acquired in step 6-1-5 (S615).

If we express this as

Time = timestamp variation * timestamp resolution

to be.

The 6-1-7 step S617 is a process of calculating the wheel speed and dividing the distance obtained in the 6-1-3 step S613 by the time obtained in the 6-1-6 step S616. to be.

In the process of changing the unit of the wheel in the 6-1-8 step (S618), since the unit of the wheel obtained in the 6-1-7 step (S617) is mm / usec, multiply it by 3600 to km / h. It is a process of converting to, and if necessary, convert it to Mile / h.

Through the above process, the wheel speed of the sixth step S610 is calculated.

The speed calculated in the state where the second validity test is performed through the third step S300 and the fifth step S500 satisfies the automotive safety integrity level ASIL D defined by ISO26262.

The sixth step (S620) is a process of acquiring a wheel speed satisfying the vehicle safety integrity level ASIL D and a vehicle speed sent from a CAN.

The third step (S630) is a process of determining whether the absolute value of the difference between the wheel speed and the vehicle speed is greater than 2KPH (Kilometer per Hour). The process proceeds to the process of not calculating the wheel speed, which is the ninth step S900, in which case, the third level validation is not satisfactory in the sixth step S600.

In addition, when the absolute value does not exceed 2KPH, which is 2 kilos per hour in step 6-3 (S630), the process proceeds to using the calculated wheel speed, which is the seventh step (S700). In S600, the third validity check is satisfied.

According to the present invention, the effect of examining stability checks for not only the wheel speed but also the vehicle speed information is generated through the sixth step S600.

Through the present invention, it is possible to make reliable wheels, and the use of such wheels produces an effect of preventing instantaneous oscillation and vibration of the electronic power steering (EPS).

In addition, it is possible to block the root cause of the occurrence of the self-steer described as a problem of the prior art, thereby enhancing the safety aspect of the driver, and the electronic power steering (when using the automatic parking assistance system). The operating reliability of EPS) can also be improved.

In addition, the effect of satisfying the Automobile Safety Integrity Level (ASIL) D as defined in ISO26262 is generated.

The foregoing description is merely illustrative of the technical idea of the present invention and various changes and modifications may be made by those skilled in the art without departing from the essential characteristics of the present invention. Therefore, the embodiments disclosed in the present invention are intended to illustrate rather than limit the scope of the present invention, and the scope of the technical idea of the present invention is not limited by these embodiments. The scope of protection of the present invention should be construed according to the following claims, and all technical ideas falling within the scope of the same shall be construed as falling within the scope of the present invention.

S100: first step S200: second step
S300: third step S400: fourth step

Claims (6)

A first step (S100), which is a process of acquiring information necessary for calculating the wheel speed;
A second step (S200) which is a process of checking a check value and a sequence number of information necessary for calculating the wheel speed after the first step (S100); and
Third step (S300) which is the first validation process performed after the second step (S200)
Method for improving the operation reliability of the automatic parking assist system, characterized in that comprises a. The method according to claim 1,
A fourth step (S400) which proceeds when the first validity is satisfied in the third step (S300) and is a process of checking a check value and a sequence number through calculation;
Method for improving the operation reliability of the automatic parking assistance system, characterized in that further comprises a fifth step (S500) which is a second validation process that proceeds after the fourth step (S400). The method according to claim 2,
Proceeds when the second validity of the fifth step (S500) is satisfied,
Step 6-1 (S610) which is a wheel speed calculation process,
A 6-2 step (S620) of acquiring the calculated wheel speed and the vehicle speed received from the can (CAN) after the 6-1 step (S610);
Third step validation process including a step 6-3 (S630) which is a process of determining whether the value represented by the absolute value of the difference between the wheel speed and the vehicle speed that proceeds after the step 6-2 (S620) exceeds the reference value How to improve the operation reliability of the automatic parking assistance system, characterized in that further comprises a sixth step (S600). The method of claim 3,
The wheel speed calculation process in step 6-1 (S610)
Step 6611-S611, which is a process of acquiring the current and previous pulse counts;
Step 6-1-2 (S612) which is a process of counting the pulse change amount that proceeds after the step 6-1-1 (S611) and
Method 6-1-3, characterized in that it comprises a 6-1-3 step (S613) which is the process of calculating the distance that proceeds after passing through the 6-1-2 step (S612). The method of claim 4,
The wheel speed calculation process in step 6-1 (S610)
Step 6-1-4 which is a process of acquiring the current and previous time stamps (S614),
A 6-1-5 step S615 which is a process of counting a change amount of the timestamp that proceeds after the 6-1-4 step S614;
6-1-6 (S616) which is a process of calculating the time that proceeds after the 6-1-5 step (S615) and
Improving operation reliability of the automatic parking assistance system, characterized in that it further comprises a 6-1-7 step (S617) that is a process for calculating the wheel speed after the 6-1-6 step (S616). Way. 6. The method according to any one of claims 1 to 5,
The process of acquiring the information necessary for calculating the wheel speed includes a wheel pulse count, a total number of pulses connected to a wheel of the vehicle, a circumferential length of the wheel, and a timestamp count. (Timestamp Count) and Timestamp Resolution (timestamp resolution) is obtained, the operation reliability improvement method of the automatic parking assist system.

Images