System And Method For Monitoring Vehicle Mass Tamper Events

• US 20130124007A1
• Filed: 01/12/2011
• Published: 05/16/2013
• Est. Priority Date: 02/15/2010
• Status: Active Grant

• Current Assignee: Transport Certification Australia, Ltd.
• Original Assignee: Transport Certification Australia, Ltd.
• Inventors: Karl, Charles, Cai, David Dajia, Davis, Lloyd, Blanksby, Chris
• Granted Patent: US 9,020,658 B2
• Time in Patent Office: Days
• US Class Current: 701/1
• CPC Class Codes: G01G 19/086 wherein the vehicle mass is dynamically estimated
• CPC Class Codes: G06F 17/00 Digital computing or data processing equipment or methods, specially adapted for specific functions information retrieval, database structures or file system structures therefor G06F16/00

Abstract

A system for detecting a mass tamper event affecting a vehicle mass record for a vehicle being monitored includes a body bounce frequency estimator configured to estimate body bounce frequency for the vehicle and a mass estimator configured to estimate a vehicle mass, m, according to the equation (I), where k is a constant relating to a suspension system in the vehicle and ω_b is the estimated body bounce frequency. A first comparator compares the estimated vehicle mass value with an alternative vehicle mass value and identifies a mass tamper event when the estimated vehicle mass value differs from the alternative vehicle mass value by more than a pre-determined amount. An interface communicates mass tamper event data to a remote device. A system and method for recording vehicle mass data are also provided.

$\begin{array}{cc}m=\frac{k}{{\omega }_b^2}& \left(I\right)\end{array}$

Claims

1-48. -48. (canceled)

49. A system for detecting a mass tamper event affecting a vehicle mass record for a vehicle being monitored, the system including:

a. a body bounce frequency estimator configured to estimate body bounce frequency for the vehicle;

b. a mass estimator configured to estimate a vehicle mass, m, according to the equation

50. A system for detecting a mass tamper event according to claim 49 wherein the pre-determined amount is about 2-7%.

51. A system for detecting a mass tamper event according to claim 50 wherein the pre-determined amount is about 2-5% for a tighter tolerance.

52. A system for detecting a mass tamper event according to claim 50, wherein the pre-determined amount is about 3-7% for a looser tolerance.

53. A system for detecting a mass tamper event according to claim 49, further including an on-board mass-monitoring unit (OBMU) configured to generate dynamic mass data during a period of operation of the vehicle, wherein the body bounce frequency estimator uses the dynamic mass data to determine body bounce frequency for the vehicle or an axle group of the vehicle.

54. A system for detecting a mass tamper event according to claim 53 wherein the dynamic mass data is sampled from the OBMU at a sampling frequency of at least 20 Hz, preferably at least 28 Hz and more preferably at least 30 Hz.

55. A system for detecting a mass tamper event according to claim 53, including a data storage element, wherein the device is configurable to store a subset of time-marked dynamic mass data records corresponding to a period of vehicle operation in which a tamper event is detectable.

56. A system for detecting a mass tamper event according to claim 49, further including an axle hop frequency estimator configured to estimate an axle hop frequency for the vehicle during a period of operation of the vehicle, and a second comparator configured to compare the estimated axle hop frequency with a predetermined range of axle hop frequencies and identifying a tamper event when the estimated axle-hop frequency is outside the predetermined range.

57. A system for detecting a mass tamper event according to claim 56 wherein the predetermined range is 10 to 15 Hz and more preferably, 12 to 14 Hz.

58. A system for detecting a mass tamper event according to claim 49, wherein the alternative vehicle mass value is obtained from static mass data recorded by a vehicle operator or other human or machine interface, or derived from dynamic mass data values obtained during a period of operation of the vehicle using a calculation selected from the group including:

a mean of dynamic mass data values;

a median of dynamic mass data values; and

a rolling average of dynamic mass data values.

59. A system for detecting a mass tamper event according to claim 58 including a third comparator configured to compare a derived mass value with a static mass value and to identify a mass tamper event when the derived mass value and the static mass value differ by more than an acceptable amount.

60. A system for detecting a mass tamper event affecting a vehicle mass record for a vehicle being monitored, the system including:

a. an on-board mass monitoring unit (OBMU) configured to generate dynamic mass data during a period of operation of the vehicle;

b. a mass deriving element configured to derive a mass value using the dynamic mass data; and

c. a mass comparator configured to compare the derived mass value with a static mass value and to identify a mass tamper event when the derived mass value and the static mass value differ by more than an acceptable amount.

61. A system for detecting a mass tamper event according to claim 60 including:

a. a body bounce frequency estimator configured to estimate body bounce frequency for the vehicle or an axle group of the vehicle using the dynamic mass data;

b. a mass estimator configured to estimate a vehicle mass, m, according to the equation

62. A system for detecting a mass tamper event according to claim 61 wherein the pre-determined amount is about 2-7%, and preferably about 2-5% for a tighter tolerance or about 3-7% for a looser tolerance.

63. A system for detecting a mass tamper event according to claim 60, including an axle hop frequency estimator configured to estimate an axle hop frequency for the vehicle during a period of operation of the vehicle, and a second comparator configured to compare the estimated axle hop frequency with a predetermined range of axle hop frequencies and identifying a tamper event when the estimated axle-hop frequency is outside the predetermined range.

64. A system for detecting a mass tamper event according to claim 63 wherein the predetermined range is 10 to 15 Hz and more preferably, 12 to 14 Hz.

65. A system for detecting a mass tamper event according to claim 60, wherein the derived mass value is determined using a calculation method selected from the group including:

mean of dynamic mass data values;

a median of dynamic mass data values; and

a rolling average of dynamic mass data values.

66. A method for detecting a mass tamper event affecting a mass record for a vehicle being monitored, including the steps of:

a. processing data obtained during a period of operation of the vehicle to provide an estimate of body bounce frequency ω

_b for the vehicle;

b. estimating vehicle mass, m, according to the equation;

67. A method for detecting a mass tamper event according to claim 66 wherein the processed data is dynamic mass data obtained during the period of vehicle operation from an on board mass-monitoring unit (OBMU) fitted to the vehicle.

68. A method for detecting a mass tamper event according to claim 66, wherein the pre-determined amount is about 2-7% and preferably about 2-5% for a tighter tolerance or about 3-7% for a looser tolerance.

69. A method for detecting a mass tamper event according to claim 67 wherein the dynamic mass data is sampled from the OBMU at a sampling frequency which is at least double an axle hop frequency of the vehicle.

70. A method for detecting a mass tamper event according to claim 67, wherein the dynamic mass data is sampled from the OBMU at a sampling frequency of at least 20 Hz, preferably at least 28 Hz and more preferably at least 30 Hz.

71. A method for detecting a mass tamper event according to claim 67, including the step of storing a subset of the dynamic mass data containing mass values corresponding to a period of vehicle operation during which a mass tamper event is detectable.

72. A method for detecting a tamper event according to claim 71 including the step of transmitting to a remote device the subset of the dynamic mass data as evidence of a mass tamper event.

73. A method for detecting a mass tamper event according to claim 66, including the step of processing the data to estimate axle hop frequency for the vehicle and comparing the estimated axle hop frequency with a pre-determined range of axle hop frequencies, wherein a tamper event is detected when the estimated axle hop frequency is outside the pre-determined range.

74. A method according to claim 73 wherein the pre-determined range of axle hop frequencies is 10-15 Hz and preferably 12-14 Hz.

75. A method for detecting a mass tamper event affecting a vehicle mass record for a vehicle being monitored, including the steps of:

a. collecting dynamic mass data from an on board mass-monitoring unit (OBMU);

b. deriving a mass value using the dynamic mass data;

c. comparing the derived mass value with a static mass value provided by the vehicle'"'"'s driver; and

d. identifying a mass tamper event when the derived mass value and the static mass value differ by more than an acceptable amount.

76. A method according to claim 75, wherein the derived mass value is determined using a calculation method selected from the group including:

a mean of dynamic mass data values;

a median of dynamic mass data values; and

a rolling average of dynamic mass data values.

77. A method according to claim 75, including the steps of:

e. processing the dynamic mass data values to provide an estimate of body bounce frequency ω

_b for the vehicle;

f. estimating vehicle mass, m, according to the equation;

78. A method for detecting a mass tamper event according to claim 77, wherein the pre-determined amount is about 2-7% and preferably about 2-5% for a tighter tolerance or about 3-7% for a looser tolerance.

79. A method for detecting a mass tamper event according to claim 75, wherein the dynamic mass data is sampled from the OBMU at a sampling frequency of at least twice an axle hop frequency of the vehicle, such as at least 20 Hz, preferably at least 28 Hz and more preferably at least 30 Hz.

80. A method for detecting a mass tamper event according to claim 75 including the step of storing a subset of the dynamic mass data containing mass values corresponding to a period of vehicle operation during which a mass tamper event is detectable.

81. A method for detecting a tamper event according to claim 80 including the step of transmitting to a remote device the subset of dynamic mass data evidencing a mass tamper event.

82. A method for detecting a mass tamper event according to claim 75, including the steps of processing the dynamic mass data to estimate an axle hop frequency for the vehicle and comparing the estimated axle hop frequency with a pre-determined range of axle hop frequencies, wherein a tamper event is detected when the estimated axle hop frequency is outside the pre-determined range.

83. A method according to claim 82 wherein the pre-determined range of axle hop frequencies is 10-15 Hz and preferably 12-14 Hz.

84. A system for recording vehicle mass including:

a. one or more on-board mass monitoring units (OBMUs) configured to generate dynamic mass data during a period of operation of the vehicle;

b. a user interface having input means operable by the user to capture from the dynamic mass data a static mass value; and

c. a storage element configured to store one or more captured static mass values.

85. A system for recording vehicle mass according to claim 84 wherein the storage element is configured to store dynamic mass data values at regular intervals.

86. A system for recording vehicle mass according to claim 84, wherein the system is configurable to store one or both of dynamic mass values and static mass values for each of a plurality of axle groups in a vehicle.

87. A system for detecting a mass tamper event incorporating the system for recording vehicle mass according to claim 84.

88. A method for recording vehicle mass including the steps of:

a. monitoring output from an on board mass-monitoring unit (OBMU) associated with the vehicle and generating dynamic mass data during a period of vehicle operation;

b. receiving an input from a user of the vehicle and causing a processor to capture from the dynamic mass data a static mass value; and

c. storing the static mass value in a storage element.

89. A method for recording vehicle mass according to claim 88 including the step of storing in the storage element a set of dynamic mass values captured from the dynamic mass data at regular intervals during a period of vehicle operation.