Abstract

ABSTRACT:A device (100) in a vehicle (1000), adapted to determine a velocity (Vestimated) of the own vehicle (1000) is disclosed. The device comprises, a first time stamp generation means (10), adapted to generate a first time stamp (1010) corresponding to at least one point (500, 550) located in the vicinity of the vehicle (1000), a second time stamp generation means (20), adapted to generate a second time stamp (1020) corresponding to the at least one point (500, 550) located in the vicinity of the vehicle (1000) and a velocity determining means (50), determining the velocity of the vehicle (1000) depending on the first time stamp (1010) and the second time stamp (1020). (Figure 1)

Information

Application ID	4153/CHE/2011
Invention Field	PHYSICS
Date of Application	2011-11-30
Publication Number	25/2013

Applicants

Name	Address	Country	Nationality
ROBERT BOSCH ENGINEERING AND BUSINESS SOLUTIONS LIMITED	123, INDUSTRIAL LAYOUT, HOSUR ROAD, KORMANGALA, BANGALORE - 560 095	India	India
ROBERT BOSCH GMBH	STUTTGART, FEUERBACH	Germany	Germany

Inventors

Name	Address	Country	Nationality
SANDIPTO NEOGI	123, INDUSTRIAL LAYOUT, HOSUR ROAD, KORMANGALA, BANGALORE - 560 095	India	India
RAGHAVENDRA S K	123, INDUSTRIAL LAYOUT, HOSUR ROAD, KORMANGALA, BANGALORE - 560 095	India	India

Specification

FIELD OF THE INVENTION

The current invention relates to determining a velocity of a vehicle. The invention shows a device equipped in a vehicle and using proximity sensors located on the vehicle to determine the velocity of the vehicle, especially when the vehicle is in a park pilot mode or when the vehicle is a autonomously guided vehicle.

BACKGROUND OF THE INVENTION

Proximity sensors are used in a park pilot system in a vehicle for determining an empty slot in a parking area where the vehicle can be parked. The park pilot system in the vehicle requires the velocity of the vehicle in decision making regarding the parking of the vehicle. Currently, the velocity of the vehicle is obtained from the speed sensors located in the vehicle. The speed sensors in existing vehicles are always an integral part of the vehicle (proprioceptive sensors).

Proximity sensors are also used for recording the speed of a vehicle travelling on a road. Typically the proximity sensors are located by the side of the road or are placed under a bridge which crosses over the road. The speed so recorded by proximity sensors can be used by the speed enforcement departments or can be displayed to a driver of the vehicle. The speed recording is done for controlling the speed of the vehicle that is being driven.

DESCRIPTION OF THE INVENTION

The core of the current invention is a device equipped in a vehicle and determining the velocity of the vehicle. According to the present invention, this is done by the features of the independent claims.
The device of the current invention estimates velocity from measurements of signals whose variation is due to a variation of a physical situation (like the vehicle moving past other objects). This invention relies primarily on exteroceptive sensors. The device is equipped in the vehicle and the velocity of the own vehicle is advantageously determined in contrast to prior art, wherein a stationary object determines the velocity of some other moving vehicle.

The device comprises a first time stamp generation means, adapted to generate a first time stamp corresponding to at least one point located in the vicinity of the vehicle, a second time stamp generation means, adapted to generate a second time stamp corresponding to the at least one point located in the vicinity of the vehicle and a velocity determining means, determining the velocity of the vehicle depending on the first time stamp and the second time stamp.

The first time stamp generation means and the second time stamp generation means can be a proximity sensor measuring a distance between the vehicle and the at least one point in the vicinity of the vehicle or a visual sensor capturing images of the at least one point in the vicinity of the vehicle. The at least one point in the vicinity of the vehicle could advantageously be another vehicle parked by the side of the road or a lamp post by the side of the road etc. The first time stamp by first time stamp generation means and the second time stamp by the second time stamp generation means are generated as a result of at least one event corresponding to the point in the vicinity of the vehicle.

In one aspect of the current invention, the event is a change in the distance measured between the vehicle and the point in the vicinity of the vehicle, in case of the proximity sensor. For a visual sensor this could be the image itself, which acts as the event. The velocity of the vehicle is determined by the velocity determining means depending on a time count derived from the first time stamp and the second time stamp. Since the first time stamp and second time stamp are generated as a result of the event corresponding to the point in the vicinity of the vehicle, a difference value of the first time stamp and second time stamp advantageously shows a relation with the velocity of the vehicle. The velocity is further derived depending on a distance between the first time stamp generation means and the second time stamp generation means. The distance between the first time stamp generation means and the second time stamp generation means is a constant for a particular measurement of the time stamps.

A pre-defined relation between the velocity of the vehicle and the difference value of the first time stamp and second time stamp for a distance between the first time stamp generation means and the second time stamp generation means can be conveniently stored in a memory of the device of the current invention. During normal running of the vehicle, the difference value can be directly mapped to the velocity of the vehicle depending on the distance between the first time stamp generation means and the second time stamp generation means. Thus, the velocity is easily determined. In the context of the current invention, it has to be understood that the velocity of the vehicle which is a vector defines the speed of the vehicle either in a forward direction or a reverse direction.

The current invention further shows a method to determine the velocity of the vehicle. The method comprising the steps of, generating a first time stamp corresponding to at least one point located in the vicinity of the vehicle, from a first time stamp generation means located on the vehicle, generating a second time stamp corresponding to the at least one point located in the vicinity of the vehicle, from a second time stamp generation means located on the vehicle, determining the velocity of the vehicle depending on the first time stamp and the second time stamp.

SHORT DESCRIPTION OF THE DRAWINGS:

An exemplifying embodiment of the invention is explained in principle below with reference to the drawings. The drawings are,

Figure 1 shows a block diagram of the device of the current invention;

Figure 2 shows a typical city street scenario, showing an example of the operation of the device of current invention;

Figure 3a and 3b show a variation of the distance measured by the device of the current invention for the example of figure 2;

Figure 4a and 4b show a variation of the velocity of the vehicle and the value of sample counts; and

Figure 5 shows a relation between the estimated velocity of the vehicle and the measured value of sample count difference value.

DESCRIPTION OF THE EMBODIMENTS

Figure 1 shows a block diagram of the device 100 of the current invention which can be equipped in a vehicle. The device 100 has a first time stamp generation means 10 receiving a first information 101 and a second time stamp generation means 20 receiving a second information 102 corresponding to at least one point 500, 550 in the vicinity of the vehicle. The first time stamp generation means 10 generates a first time stamp 1010 depending on first information 101 and the second time stamp generation means 20 generates a second time stamp 1020 depending on second information 102. The first time stamp 1010 and the second time stamp 1020 are then received by a velocity determining means 50 and the velocity 201 of the vehicle is determined.

. Figure 2 shows an example of a typical scenario of a city road wherein the ego vehicle 1000 equipped with the device 100, is travelling. The ego vehicle 1000 assumes different positions, namely position A, position B and position C along with its forward movement. The first time stamp generation means 10 and the second time stamp generation means 20 can be proximity sensors located on the periphery of the vehicle detecting distance between the vehicle and the at least one point 500, 550 in the vicinity of the vehicle. The at least one point 500, 550 in the vicinity of the vehicle can be another vehicle parked by the side of the road or an empty parking slot in the road.

Typically, a park pilot system in a vehicle, of which the device 100 could be an element, works on the principle of detecting an empty slot for parking. The velocity of the vehicle 1000 is necessary for the park pilot system for estimating the length of the parking slot and additionally can be useful for automatically parking the vehicle 1000. The first time stamp generation means 10 and the second time stamp generation means 20 can be located on all four corners of the vehicle as shown in the figure 2. But, the device of the current invention works for a pair of time stamp generation means 10, 20 on any one side of the vehicle 1000, for example the right side. The time stamp generation means 10, 20 are separated by a length dR on the vehicle body.

The device can be extended by considering time stamps generated by both the sides (left and right) for better results. The time stamp generation means 10, 20 can be separated by a length dL when the left side of the vehicle is also considered. Another embodiment may use multiple sensors on any one side of the vehicle, capable of generating multiple events, and thus could be useful for better estimates of velocity and also act as a failure mitigation scheme in the event one of the sensors fail.

The proximity sensors 10, 20 of the current example continuously measure a distance D between the vehicle and the points 500, 550 in the vicinity of the vehicle. The distance D is measured for each sample of the operation of the proximity sensors 10, 20. The distance D varies for each point 500, 550 in the vicinity of the vehicle. For example as shown in figure 2, a distance Di is measured with respect to the point 550 and a distance D2 is measured with respect to the point 500 in the vicinity of the vehicle.

Figure 3a and figure 3b show a variation of the distance D measured by the proximity sensor 10, 20 for each sample of the operation of the device 100 for the example as shown in figure 2. The Y-axis shows the distance D measured by the proximity sensor and the X-axis shows the sample count N for each measurement. Now, since the vehicle is moving in a forward direction, the first time stamp generation means 10 (proximity sensor) detects the distance D with respect to the point 550 (Di) and then a distance is measured with respect to point 500 (D2) in the vicinity of the vehicle. This is shown by the curve 101.

Since the two points 500 and 550 are at different distances D1, D2 respectively from the vehicle the curve 101 shows the variation. Similarly, the second time stamp generation means 20 generates the curve 102. The transition from the point 550 to 500 in the distance D measurement gives an event 1010,1020 with respect to the first time stamp generation means 10 and second time stamp generation means 20 respectively. Since the second time stamp generation means 20 is following the first time stamp generation means 10, the event 1020 occurs at a later sample count than the first event 1010.

The difference n1, n2 between the sample counts at which the first event 1010 occurs and the second event 1020 occurs, depends on the speed at which the vehicle is travelling. Also, the samples are obtained at a pre-defined interval of time, the difference value nl, n2 can be related to a time t1, t2. Higher the speed of the vehicle, lower is the time count. Hence nl < n2 (which translates to tl< t2) denotes that the vehicle is travelling at a higher speed in the example of figure 3a, than the speed in the example of 3b. The first event 1010 and the second event 1020 can also be translated to be the first time stamp 1010 and the second time stamp 1020.

Further since the distance D measured by the first time stamp generation means 10 occurs before the distance measured by the second time stamp generation means 20, it can be easily determined that the vehicle is moving in a forward direction. Hence with the determination of the speed of the vehicle the direction of travel (forward or rearward) can also be determined and hence the velocity.

Figure 4a and figure 4b show the variation vl, v2, v3, v4 of the velocity of the vehicle with respect to the sample count difference values nl, n2, n3, n4 which are related to a time count tl, t2, t3, t4 respectively.

The curve 800 shows the variation for a fixed length drl between the first time stamp generation means 10 and the second time stamp generation means 20. Figure 4b further shows a variation 800, 801, 802 at different fixed length value drl, dr2, dr3 between the two time stamp generation means 10, 20 (proximity sensors) respectively. The length drl, dr2, dr3 is a fixed value for a particular measurement of distance D by the first time stamp generation means 10 and the second time stamp generation means 20.

The variation of the velocity vl, v2, v3, v4 for different sample count values nl, n2, n3, n4 is dependent on the length between the two proximity sensors 10, 20. The variation curves 800, 801, 802 can be conveniently pre-stored in a memory of the device 100. Then depending on the measured sample count difference value nmeasured as shown in figure 5, the velocity determination means 50 determines the velocity vestimated of the vehicle 1000 along with the knowledge of the fixed length dR between the proximity sensors and from the pre- stored variation curve 800, 801, 802.

In case of a visual sensor, the images taken of the points 500, 550 by two visual sensors 10, 20 located on the periphery of the vehicle can be compared to generate the event 1010, 1020 and hence the time stamps.

The device 100 of the current invention can also be used on autonomously guided vehicle such as lawn mower or in automatic vehicles used in industrial production plants. Further, the method of the current invention can also be extended not just for the velocity of a vehicle but also for determining the rotating speed of a rotating device on which the device 100 of the current invention can be located.

Additionally the device 100 of the current invention can be coupled with other sensors like yaw angle sensor, compass sensor or gyroscope etc. In this way it is possible to improve/correct the estimation of the velocity of the vehicle even when the vehicle is not moving in a straight line past the stationary objects, but at an angle to the objects. Further, more accurate information about the direction of travel of the vehicle can be derived by using such additional sensors along with the device 100 of the current invention.

It must be understood that the embodiments explained in the above detailed description in only illustrative and does not limit the scope of this invention. The scope of this invention is limited only by the scope of the claims. Many modification and changes in the embodiments aforementioned are envisaged and are within the scope of this invention.

WE CLAIM:

1. A device (100) equipped in a vehicle (1000), adapted to determine a velocity (vestimeted) of
said vehicle (1000), comprising,

- a first time stamp generation means (10), adapted to generate a first time stamp
(1010) corresponding to at least one point (500, 550) located in the vicinity of said vehicle
(1000),

- a second time stamp generation means (20), adapted to generate a second time
stamp (1020) corresponding to said at least one point (500, 550) located in the vicinity of
said vehicle (1000),

- a velocity determining means (50), determining the velocity of said vehicle (1000)
depending on said first time stamp (1010) and said second time stamp (1020).

2. The device (100) as claimed in claim 1, wherein said first time stamp generation means (10) and said second time stamp generation means (20) is one of a visual sensor or a proximity sensor.

3. The device (100) as claimed in claim 1, wherein said first time stamp (1010) by first time
stamp generation means (10) and said second time stamp (1020) by said second time stamp
generation means (20) are generated as a result of at least one event.

. 4. The device (100) as claimed in claim 2 and 3, wherein said at least one event in said proximity sensor (10, 20) is a change in distance (D) measured corresponding to said at least one point (500, 550) located in the vicinity of said vehicle (1000).

5. The device (100) as claimed in claim 2 and 3, wherein said at least one event in said visual sensor (10, 20) is at least one image captured corresponding to said at least one point (500, 550) located in the vicinity of said vehicle (1000).

6. The device (100) as claimed in claim 1, wherein the velocity of the vehicle (1000) is determined by said velocity determining means (50) depending on a time count (nl, n2, n3, n4, nmeasured) derived from said first time stamp (1010) and said second time stamp (1020).

7. The device (100) as claimed in claim 6, wherein said time count (n1, n2, n3, n4, nmeasured) is
an absolute difference value of said first time stamp (1010) and said second time stamp
(1020).

8. The device (100) as claimed in claim 1, wherein the velocity (vestimated) of the vehicle (1000) is further determined by said velocity determining means (50) depending on a distance (drl, dr2, dr3) between said first time stamp generation means (10) and said second time stamp generation means (20).

9. A method to determine a velocity (vestimated) of a vehicle (1000), comprising the steps,

- generating a first time stamp (1010) corresponding to at least one point (500, 550) located in the vicinity of said vehicle (1000), from a first time stamp generation means (10) located on said vehicle (1000),

- generating a second time stamp (1020) corresponding to said at least one point (500, 550) located in the vicinity of said vehicle (1000), from a second time stamp generation means (20) located on said vehicle (1000),

- determining the velocity (vestimated) of said vehicle (1000) depending on said first
time stamp (1010) and said second time stamp (1020).

Documents

Name	Date
4153-CHE-2011 FORM-3 30-11-2011.pdf	2011-11-30
4153-CHE-2011 FORM-2 30-11-2011.pdf	2011-11-30
4153-CHE-2011 POWER OF ATTORNEY 30-11-2011.pdf	2011-11-30
4153-CHE-2011 FORM-1 30-11-2011.pdf	2011-11-30
4153-CHE-2011 DRAWINGS 30-11-2011.pdf	2011-11-30
4153-CHE-2011 DESCRIPTION (COMPLETE) 30-11-2011.pdf	2011-11-30
4153-CHE-2011 CLAIMS 30-11-2011.pdf	2011-11-30
4153-CHE-2011 CORRESPONDENCE OTHERS 30-11-2011.pdf	2011-11-30
4153-CHE-2011 FORM-18 24-02-2014.pdf	2014-02-24
4153-CHE-2011 ABSTRACT 30-11-2011.pdf	2011-11-30
4153-CHE-2011-FER.pdf	2019-03-27
4153-CHE-2011 FORM-5 30-11-2011.pdf	2011-11-30
4153-CHE-2011-FER_SER_REPLY [26-09-2019(online)].pdf	2019-09-26
4153-CHE-2011-FORM 13 [26-09-2019(online)].pdf	2019-09-26
4153-CHE-2011-OTHERS [26-09-2019(online)].pdf	2019-09-26
4153-CHE-2011-DRAWING [26-09-2019(online)].pdf	2019-09-26
4153-CHE-2011-CLAIMS [26-09-2019(online)].pdf	2019-09-26
4153-CHE-2011-ABSTRACT [26-09-2019(online)].pdf	2019-09-26
4153-CHE-2011-US(14)-HearingNotice-(HearingDate-09-11-2022).pdf	2022-09-08
4153-CHE-2011-COMPLETE SPECIFICATION [26-09-2019(online)].pdf	2019-09-26
4153-CHE-2011-PatentCertificate23-12-2022.pdf	2022-12-23
4153-CHE-2011-Annexure [09-11-2022(online)].pdf	2022-11-09
abstract4153-CHE-2011.jpg	2012-11-24
4153-CHE-2011-CORRESPONDENCE [26-09-2019(online)].pdf	2019-09-26
4153-CHE-2011-RELEVANT DOCUMENTS [26-09-2019(online)].pdf	2019-09-26
4153-CHE-2011-Response to office action [23-11-2022(online)].pdf	2022-11-23
4153-CHE-2011-Annexure [23-11-2022(online)].pdf	2022-11-23
4153-CHE-2011-Response to office action [09-11-2022(online)].pdf	2022-11-09
4153-CHE-2011-IntimationOfGrant23-12-2022.pdf	2022-12-23

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