Vehicle overturn monitor

• US 6,185,489 B1
• Filed: 06/12/1998
• Issued: 02/06/2001
• Est. Priority Date: 06/12/1998
• Status: Expired due to Fees

• Current Assignee: Roger Dean Strickler
• Original Assignee: Roger Dean Strickler
• Inventors: Strickler, Roger Dean
• Primary Examiner(s): Cuchlinski, Jr., William A.
• Assistant Examiner(s): Marc-Coleman, Marthe Y.
• Application Number:
  US09/096,292
• Time in Patent Office: 970 Days
• Field of Search: 701/1, 701/36, 701/38, 701/29, 701/35, 701/46, 340/440, 340/438, 180/268
• US Class Current: 701/29
• CPC Class Codes: B60G 17/0162 mainly during a motion involving steering operation, e.g. cornering, overtaking B60G17/0164 takes precedence
• CPC Class Codes: B60G 2400/102 vertical
• CPC Class Codes: B60G 2400/104 lateral or transversal with regard to vehicle
• CPC Class Codes: B60G 2400/63 Location of the center of gravity
• CPC Class Codes: B60G 2400/841 Wind
• CPC Class Codes: B60G 2600/044 Alarm means
• CPC Class Codes: B60G 2800/012 Rolling condition
• CPC Class Codes: B60G 2800/24 Steering, cornering
• CPC Class Codes: B60G 2800/704 predicting unorthodox driving conditions for safe or optimal driving
• CPC Class Codes: B60G 2800/9124 Roll-over protection systems, e.g. for warning or control
• CPC Class Codes: B60R 16/0233 Vehicle tilting, overturning or roll over

Abstract

A vehicle overturn monitor includes an input/display device that enables vehicle load information to be entered by positioning a left side and a right side critical angle display, cursor, or other indicator at a point on the display representative of a calculated critical angle β for each side of the vehicle, the critical angle display enabling a maximum safe speed to be determined based on posted curve radius and bank information using a chart of maximum speeds as a function of the curve radius, with the control device for each indicator turning a potentiometer that controls both the critical angle display and an input to a comparator that triggers an alarm, the second input to the comparator being provided by circuitry having as input a plurality of force or acceleration sensors that monitor the actual forces on the vehicle and control illumination of a second set of LEDs to provide a visual indication of the net force vector. The input/display device of the vehicle overturn monitor thus provides a continuous indication of how close the force vector on the vehicle is to the critical angle and a visual/audible warning of imminent danger, as well as an indication of the speed at which the curve may safely be entered, all based on the turning of a knob that moves a critical angle indicator to a point selected by inputting the location of the load into a simple mathematical formula.

Claims

1. A vehicle overturn monitor, comprising:

means for determining and displaying a critical angle at which a vehicle is likely to overturn, the critical angle having been predetermined based on input vehicle and load information;

means for displaying an angle of net dynamic forces on the vehicle during negotiation of the curve by continuously monitoring a net dynamic force vector resulting from said forces, said forces including forces resulting from crosswind pressure, vehicle vertical acceleration, and vehicle lateral acceleration, for comparison with the displayed predetermined critical angle;

means for automatically comparing said net dynamic force vector with the critical angle and alerting the operator of the vehicle when the net dynamic force vector approaches the critical angle; and

means for enabling the operator of a vehicle to easily determine safe speeds for negotiating a curve before the vehicle negotiates the curve based on said critical angle and on curve radii and bank information posted in a manner visible to the operator of the vehicle as the vehicle approaches the curve.

2. A vehicle overturn monitor including a device for providing a continuous display of overturn probability, comprising:

a critical angle display;

an operator input device for controlling the critical angle display;

at least one sensor for measuring a quantity corresponding to a dynamic force that contributes to a net dynamic force that may potentially cause the vehicle to overturn during negotiation of the curve if the direction of the net dynamic force exceeds the critical angle; and

a dynamic force display connected to the circuit for displaying a direction of a net dynamic force on the vehicle,

wherein the critical angle display and the dynamic force display are included in a display unit so as to permit an operator of a vehicle to continuously monitor how close the direction of the net dynamic force is to the critical angle, and thereby determine how close the vehicle is to turning over.

3. A monitor as claimed in claim 2, wherein the at least one sensor includes at least one sensor arranged to measure a lateral acceleration of the vehicle.

4. A monitor as claimed in claim 3, wherein the at least one sensor includes an additional sensor arranged to measure a wind pressure on the vehicle, further comprising a circuit arranged to calculate an acceleration of the vehicle corresponding to the measured wind pressure, and to add the measured lateral acceleration to the calculated acceleration corresponding to the wind pressure.

5. A monitor as claimed in claim 4, further comprising a circuit for calculating a wind speed based on the measured wind pressure, and a display device connected to the wind speed calculating circuit for displaying the calculated wind speed.

6. A monitor as claimed in claim 5, wherein the at least one sensor also includes a vertical acceleration sensor, wherein the circuit is further arranged to continuously combine a vertical acceleration measured by the vertical acceleration sensor with the sum of the measured lateral acceleration and the calculated wind pressure acceleration, and wherein the dynamic force display is arranged to continuously display a result of the combination.

7. A monitor as claimed in claim 6, wherein:

the lateral and vertical acceleration sensors are accelerometers arranged to output corresponding electrical signals whose magnitude is proportional to the respectively measured vertical and lateral accelerations,

the calculated wind pressure acceleration is represented by a corresponding electrical signal whose magnitude is proportional to the calculated wind pressure acceleration,

the measured lateral acceleration and the calculated wind pressure acceleration are combined by summing the corresponding electrical signals at a node in the circuit,

the measured vertical acceleration is supplied to a voltage divider network comprising a plurality of resistors connected together by connection points, the connection points each being connected to a first input of a respective comparator, an output of each respective comparator being connected to a visible indicator, and

a second input of each of the comparators being connected to the node at which the measured lateral acceleration and the calculated wind pressure acceleration are combined,

whereby a number of said visual indicators that are activated by outputs of said comparators corresponds to the relative magnitude of lateral and vertical forces, and therefore to a direction of said forces.

8. A monitor as claimed in claim 7, wherein

said critical angle is represented by a magnitude of an electrical signal adjustable by an operator input,

a reference electrical signal is supplied to a second voltage divider network comprising a second plurality of resistors connected together by second connection points, the second connection points each being connected to a first input of a respective second comparator, an output of each respective second comparator being connected to a second visible indicator, and

the electrical signal representing the critical angle is supplied to a second input of each of the second comparators,

whereby a number of said second visual indicators that are activated by outputs of said comparators corresponds to the critical angle, said second visual indicators forming said critical angle display.

9. A monitor as claimed in claim 8, wherein said first and second visual indicators are LEDs.

10. A monitor as claimed in claim 8, wherein said operator input is a potentiometer adjustable by a knob, whereby said critical angle is calculated based on load and vehicle parameters, and said critical angle display is adjusted by turning said knob until said critical angle display displays the calculated critical angle, at which time the load and vehicle parameters have been effectively input to said monitor.

11. A monitor as claimed in claim 8, further comprising a comparison circuit for comparing the signal representative of the critical angle with a signal representative of the direction of the combined vertical and lateral forces, and for activating an alarm when the direction of the combined vertical and lateral forces approaches the critical angle.

12. A monitor as claimed in claim 8, wherein said alarm includes a buzzer and a flasher circuit for causing illuminated ones of said second visual indicators to flash on and off.

13. A monitor as claimed in claim 2, wherein the critical angle display includes a first row of light emitting diodes and the dynamic force vector display includes a second row of light emitting diodes, the first row of light emitting diodes being driven by a first circuit whose output is determined by a manually adjustable circuit element, and the second row of light emitting diodes being driven by said force direction deriving circuit.

14. A monitor as claimed in claim 13, wherein said manually adjustable circuit element is a potentiometer adjustable by a knob, whereby said critical angle is calculated based on load and vehicle parameters, and said critical angle display is adjusted by turning said knob until said critical angle display displays the calculated critical angle, at which time the load and vehicle parameters have been effectively input to said monitor.

15. A monitor as claimed in claim 13, further comprising a comparison circuit for comparing the signal representative of the critical angle with a signal representative of the direction of the combined vertical and lateral forces, and for activating an alarm when the direction of the combined vertical and lateral forces approaches the critical angle.

16. A vehicle overturn monitor including a device for providing a warning that an overturn is imminent, comprising:

an operator input device for inputting information enabling predetermination of a critical angle;

at least one sensor for measuring a quantity indicative of a lateral force on the vehicle and at least one sensor for measuring a quantity indicative of a vertical force on the vehicle;

a circuit for deriving an angle of net lateral and vertical forces on the vehicle based on inputs from the sensors;

a comparison circuit for comparing the angle of the net lateral and vertical forces on the vehicle with the input critical angle; and

an alarm circuit for alerting an operator of the vehicle that the angle of the net lateral forces on the vehicle is approaching the critical angle and that a roll over is therefore imminent.

17. A monitor as claimed in claim 16, wherein the quantity indicative of a lateral force on the vehicle is a sum of a measured lateral acceleration of the vehicle and a calculated acceleration due to wind pressure measured by a wind pressure sensor.

18. A monitor as claimed in claim 17, wherein the quantity indicative of a vertical force on the vehicle includes a measured vertical acceleration of the vehicle.

19. A monitor as claimed in claim 17, wherein the operator input device includes a potentiometer adjustable by a knob, said potentiometer determining a magnitude of an electrical signal representative of the critical angle, said comparison circuit being arranged to compare said magnitude of the electrical signal representative of the critical angle with a magnitude of a second electrical signal representative of the direction of the net lateral and vertical forces on the vehicle.

20. A monitor as claimed in claim 19, further comprising a display of the critical angle, the display being responsive to the electrical signal representative of the critical angle whose magnitude is adjusted by said potentiometer, whereby said critical angle is calculated based on load and vehicle parameters, and said critical angle display is adjusted by turning said knob until said critical angle display displays the calculated critical angle, at which time the load and vehicle parameters have been effectively input to said monitor.

21. A vehicle overturn monitor including a device for providing an indication of a maximum safe speed at which to enter a curve, comprising:

a critical angle display arranged to display a critical angle which, if exceeded by a net dynamic force on the vehicle, will result in overturning of the vehicle; and

a chart of maximum safe speeds calculated as a function of the critical angle and curve radius and arranged relative to the critical angle display such that the critical angle display directs the attention of an operator of the vehicle to a set of maximum safe speeds corresponding to the displayed critical angle and arranged according to the corresponding curve radius.

22. A monitor as claimed in claim 21, wherein the critical angle display is arranged to be manually adjusted to a calculated critical angle.

23. A monitor as claimed in claim 22, wherein the critical angle display is a light emitting diode bar display.

24. A monitor as claimed in claim 22, wherein the chart is arranged such that the critical angle display points to a column of numbers in the chart corresponding to maximum safe speeds for the critical angle, and such that rows of such numbers correspond to curve radii.

30. A monitor as claimed in claim 21, wherein the critical angle display includes a first row of light emitting diodes and the dynamic force vector display includes a second row of light emitting diodes, the first row of light emitting diodes being driven by a first circuit whose output is determined by a manually adjustable circuit element, and the second row of light emitting diodes being driven by said force direction deriving circuit.

31. A monitor as claimed in claim 30, wherein said manually adjustable circuit element is a potentiometer adjustable by a knob, whereby said critical angle is calculated based on load and vehicle parameters, and said critical angle display is adjusted by turning said knob until said critical angle display displays the calculated critical angle, at which time the load and vehicle parameters have been effectively input to said monitor.

32. A monitor as claimed in claim 21, further comprising:

an operator input device for inputting the critical angle;

at least one sensor for measuring a quantity indicative of a lateral force on the vehicle and at least one sensor for measuring a quantity indicative of a vertical force on the vehicle;

a circuit for deriving a direction of the net lateral and vertical forces on the vehicle based on inputs from the sensors;

a comparison circuit for comparing the direction of the net lateral and vertical forces on the vehicle with the input critical angle; and

an alarm circuit for alerting an operator of the vehicle that the direction of the net lateral forces on the vehicle is approaching the critical and that a roll over is therefore imminent.

33. A monitor as claimed in claim 32, wherein the quantity indicative of a lateral force on the vehicle is a sum of a measured lateral acceleration of the vehicle and a calculated acceleration due to wind pressure measured by a wind pressure sensor, and the quantity indicative of a vertical force on the vehicle includes a measured vertical acceleration of the vehicle.

34. A monitor as claimed in claim 32, wherein the operator input device includes a potentiometer adjustable by a knob, said potentiometer determining a magnitude of an electrical signal representative of the critical angle, said comparison circuit being arranged to compare said magnitude of the electrical signal representative of the critical angle with a magnitude of a second electrical signal representative of the direction of the net lateral and vertical forces on the vehicle.

25. A monitor as claimed in 21, further comprising:

an operator input device for controlling the critical angle display;

at least one sensor for measuring a quantity corresponding to a dynamic force that contributes to a net dynamic force that may potentially cause the vehicle to overturn during negotiation of the curve if the direction of the net dynamic force exceeds the critical angle; and

a dynamic force display connected to the circuit for displaying a direction of a net dynamic force on the vehicle,

wherein the critical angle display and the dynamic force display are included in a display unit so as to permit an operator of a vehicle to continuously monitor how close the direction of the net dynamic force is to the critical angle, and thereby determine how close the vehicle is to rolling over.

26. A monitor as claimed in claim 25, wherein the at least one sensor includes at least one sensor arranged to measure a lateral acceleration of the vehicle;

an additional sensor arranged to measure a wind pressure on the vehicle;

a circuit arranged to calculate an acceleration of the vehicle corresponding to the measured wind pressure, and to add the measured lateral acceleration to the calculated acceleration corresponding to the wind pressure; and

a vertical acceleration sensor, wherein the circuit is further arranged to continuously combine a vertical acceleration measured by the vertical acceleration sensor with the sum of the measured lateral acceleration and the calculated wind pressure acceleration, and wherein the dynamic force display is arranged to continuously display a result of the combination.

27. A monitor as claimed in claim 26, wherein:

the lateral and vertical acceleration sensors are accelerometers arranged to output corresponding electrical signals whose magnitude is proportional to the respectively measured vertical and lateral accelerations,

the calculated wind pressure acceleration is a corresponding electrical signal whose magnitude is proportional to the calculated wind pressure acceleration,

the measured lateral acceleration and the calculated wind pressure acceleration are combined by summing the corresponding electrical signals at a node in the circuit,

the measured vertical acceleration is supplied to a voltage divider network comprising a plurality of resistors connected together by connection points, the connection points each being connected to a first input of a respective comparator, an output of each respective comparator being connected to a visible indicator, and

a second input of each of the comparators being connected to the node at which the measured lateral acceleration and the calculated wind pressure acceleration are combined,

whereby a number of said visual indicators that are activated by outputs of said comparators corresponds to the relative magnitude of lateral and vertical forces, and therefore to a direction of said forces.

28. A monitor as claimed in claim 27, wherein

said critical angle is represented by a magnitude of an electrical signal adjustable by an operator input,

a reference electrical signal is supplied to a second voltage divider network comprising a second plurality of resistors connected together by second connection points, the second connection points each being connected to a first input of a respective second comparator, an output of each respective second comparator being connected to a second visible indicator, and

the electrical signal representing the critical angle is supplied to a second input of each of the second comparators,

whereby a number of said second visual indicators that are activated by outputs of said comparators corresponds to the critical angle, said second visual indicators forming said critical angle display.

29. A monitor as claimed in claim 28, wherein said operator input is a potentiometer adjustable by a knob, whereby said critical angle is calculated based on load and vehicle parameters, and said critical angle display is adjusted by turning said knob until said critical angle display displays the calculated critical angle, at which time the load and vehicle parameters have been effectively input to said monitor.

35. A vehicle overturn monitoring method, comprising the steps of:

pre-determining and displaying a critical angle at which a vehicle is likely to overturn based on input vehicle and load information;

displaying an angle of net dynamic forces on the vehicle during negotiation of the curve by continuously monitoring a net dynamic force vector resulting from said forces, said forces including forces resulting from crosswind pressure, vehicle vertical acceleration, and vehicle lateral acceleration, for comparison with the displayed predetermined critical angle;

automatically comparing said net dynamic force vector with the critical angle and alerting the operator of the vehicle when the net dynamic force vector approaches the critical angle; and

enabling the operator of a vehicle to easily determine safe speeds for negotiating a curve before the vehicle negotiates the curve based on said critical angle and on curve radii and bank information posted in a manner visible to the operator of the vehicle as the vehicle approaches the curve.

36. An overturn monitoring method, comprising the steps of:

predetermining a critical angle, the critical angle being the direction of net dynamic forces on the vehicle that will cause the vehicle to overturn;

controlling a critical angle display so that the critical angle display indicates the predetermined critical angle;

measuring dynamic forces on the vehicle and calculating an angle of net dynamic forces on the vehicle; and

displaying the angle of net dynamic forces on the vehicle together with the critical angle in such a manner that the display of net dynamic forces on the vehicle can be visually compared by an operator of the vehicle with the critical angle display.

37. A method as claimed in claim 36, wherein the step of calculating the critical angle comprises the step of computing a ratio of X_L,R to Y, where X_L,R and Y are defined by the formulas:

38. A method as claimed in claim 36, wherein the step of displaying the direction of net dynamic forces on the vehicle comprises the steps of:

measuring a lateral acceleration of the vehicle using a lateral accelerometer;

measuring a vertical acceleration of the vehicle using a vertical accelerometer;

measuring a wind pressure on the vehicle using a wind pressure sensor;

processing an output of the wind pressure sensor to calculate an acceleration of the vehicle due to the wind pressure;

summing the measured lateral acceleration and the calculated wind pressure acceleration to obtain a summed lateral acceleration;

combining the summed lateral acceleration with the measured vertical acceleration to obtain the net direction of dynamic forces on the vehicle.

39. A method as claimed in claim 38, wherein the respective sensors output electrical signals, and the processing, summing, and combining steps are carried out by supplying the output electrical signals to signal processing circuitry.

40. A method as claimed in claim 36, further comprising the step of automatically comparing the direction of net dynamic forces on the vehicle with the critical angle and alerting an operator of the vehicle when the direction of net dynamic forces on the vehicle approaches the critical angle.

41. A method as claimed in claim 36, further comprising the steps of providing a chart of maximum safe speeds as a function of the critical angle and curve radii;

observing a sign having posted thereon a radius of an approaching curve; and

locating on the chart a maximum safe speed at which the approaching curve may be negotiated based on the displayed critical angle and the posted curve radius.

42. A method as claimed in claim 41, further comprising the step of locating a different maximum speed on the chart by adding to the critical angle a posted bank angle of the approaching curve.

43. An overturn monitoring method, comprising the steps of:

predetermining a critical angle, the critical angle being the direction of net dynamic forces on the vehicle that will cause the vehicle to overturn;

inputting the predetermined critical angle to a monitoring device;

measuring dynamic forces on the vehicle and calculating an angle of net dynamic forces on the vehicle;

comparing the angle of net dynamic forces on the vehicle to the predetermined critical angle; and

activating an alarm when the angle of net dynamic forces on the vehicle equals the predetermined critical angle.

displaying the angle of net dynamic forces on the vehicle together with the critical angle in such a manner that the display of net dynamic forces on the vehicle can be visually compared by an operator of the vehicle with the critical angle display.

44. A method as claimed in claim 43, wherein the step of measuring and calculating the net dynamic force on the vehicle comprises the steps of:

measuring a lateral acceleration of the vehicle using a lateral accelerometer;

measuring a vertical acceleration of the vehicle using a vertical accelerometer;

measuring a wind pressure on the vehicle using a wind pressure sensor;

processing an output of the wind pressure sensor to calculate an acceleration of the vehicle due to the wind pressure;

summing the measured lateral acceleration and the calculated wind pressure acceleration to obtain a summed lateral acceleration; and

combining the summed lateral acceleration with the measured vertical acceleration to obtain the net direction of dynamic forces on the vehicle.

45. A method as claimed in claim 43, wherein the step of calculating the critical angle comprises the step of computing a ratio of X_L,R to Y, where X_L,R and Y are defined by the formulas:

46. A method as claimed in claim 43, further comprising the steps of providing a chart of maximum safe speeds as a function of the critical angle and curve radii;

observing a sign having posted thereon a radius of an approaching curve; and

locating on the chart a maximum safe speed at which the approaching curve may be negotiated based on the displayed critical angle and the posted curve radius.

47. A method as claimed in claim 46, further comprising the step of locating a different maximum speed on the chart by adding to the critical angle a posted bank angle of the approaching curve.

48. A method as claimed in claim 46, further comprising the step of locating a different maximum speed on the chart by adding to the critical angle a posted bank angle of the approaching curve.

49. A method as claimed in claim 48, wherein the step of calculating the critical angle comprises the step of computing a ratio of X_L,R to Y, where X_L,R and Y are defined by the formulas:

50. An overturn monitoring method, comprising the steps of

calculating a critical angle, the critical angle being the direction of net dynamic forces on the vehicle that will cause the vehicle to overturn;

controlling a critical angle display so that the critical angle display indicates the calculated critical angle;

providing a chart of maximum safe speeds as a function of the critical angle and curve radii;

observing a sign having posted thereon a radius of an approaching curve; and

locating on the chart a maximum safe speed at which the approaching curve may be negotiated based on the displayed critical angle and the posted curve radius.