US3893536A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Vehicle guidance system operating in the bang bang mode
Assignee: ERA Patents Ltd
•
Filing: 1973-11-13
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Granted: 1975-07-08
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Expires: 1993-11-13
Abstract
Abstract In a vehicle guidance system for guiding a vehicle along a path defined by a guidance conductor, the deviation of the vehicle from the path is sensed and whenever the deviation reaches a predetermined value in either direction the vehicle steering mechanism is activated to a fixed amount in the required direction for correcting the deviation. The steering mechanism remains activated by the fixed amount until the deviation is reduced below the predetermined value. The steering mechanism is then de-activated and returns to the zero position. The monitoring of the deviation is preferably carried out by sensing means which provides two signals which vary differentially depending on the deviation, the steering mechanism being activated when the difference between the signals exceeds a preset level.
Inventors
- 👤 Leonard Marshall
- 👤 David S Hobday
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-24 20:04
CPC Classifications
G; G05; G05D; G05D1/00; G05D1/02; G05D1/021; G05D1/0259; G05D1/0265
Claims Analysis
Total Claims: 16
Claim 1
Independent Claim
127 words
A guidance system for operating a steering mechanism of a vehicle for guiding the vehicle along a path defined by a guidance conductor, the system including means for sensing the deviation of the vehicle from the defined path; steering control means operable to activate said steering mechanism by a fixed amount selectively to the left or to the right about a datum condition; and means responsive to the sensed deviation to cause the steering control means to activate the steering mechanism by said fixed amount in the appropriate direction for correcting the deviation when said deviation exceeds a predetermined value, and to maintain the activation by said fixed amount until the deviation reduces below the predetermined value, the steering mechanism then being de-activated to the datum condition.
Claim 2
Dependent Claim
127 words
A guidance system for operating a steering mechanism of a vehicle for guiding the vehicle along a path defined by a guidance conductor, the system including means for sensing the deviation of the vehicle from the defined path; steering control means operable to activate said steering mechanism by a fixed amount selectively to the left or to the right about a datum condition; and means responsive to the sensed deviation to cause the steering control means to activate the steering mechanism by said fixed amount in the appropriate direction for correcting the deviation when said deviation exceeds a predetermined value, and to maintain the activation by said fixed amount until the deviation reduces below the predetermined value, the steering mechanism then being de-activated to the datum condition.
Claim 3
Dependent Claim
68 words
A system as claimed in claim 1, in which the sensing means is responsive to a flow of current in the conductor to generate two deviation signals which vary differentially in dependence upon said deviation, and in which the deviation-responsive means is responsive to the difference between the deviation signals to cause the steering control means to activate the steering mechanism when said difference exceeds a predetermined level.
Claim 4
Dependent Claim
61 words
A system as claimed in claim 2, in which the deviation-responsive means includes means for deriving an error voltage from the difference between a reference voltage representing zero deviation and a voltage representing the difference between the deviation signals; and switching means for causing operation of the steering control means when the magnitude of the error voltage exceeds a predetermined level.
Claim 5
Dependent Claim
57 words
A system as claimed in claim 3, in which the deviation-responsive means includes means for rectifying the deviation signals and for applying the resulting voltages with opposite polarities to the ends of potential divider means, the difference between the reference voltage and the voltage at a centre tap of the potential divider means providing the error signal.
Claim 6
Dependent Claim
88 words
A system as claimed in claim 3, in which the switching means includes first and second differential amplifiers to which are applied, respectively, first and second bias voltages representing the limits of a range of values of the error voltage within which range the steering control means is to be inoperative, the error voltage being applied to both said first and second amplifiers to cause one or the other of the amplifiers to change its conductivity state when the value of the error voltage is outside said range.
Claim 7
Dependent Claim
32 words
A system as claimed in claim 2, including means operable in response to an excessive reduction in the sum of the deviation signals to cause arresting of the movement of the vehicle.
Claim 8
Dependent Claim
25 words
A system as claimed in claim 2, including means responsive to loss of said deviation signals to cause arresting of the movement of the vehicle.
Claim 9
Dependent Claim
48 words
A system as claimed in claim 2, including separate sensing means adjacent the front and rear, respectively, of the vehicle; and means responsive to the loss of deviation signals from only one or the other sensing means to cause reversal of the direction of movement of the vehicle.
Claim 10
Dependent Claim
33 words
A system as claimed in claim 6, including means for temporarily overriding the means operable in response to said excessive reduction during initial positioning of the vehicle with respect to the guidance conductor.
Claim 11
Dependent Claim
33 words
A system as claimed in claim 7, including means for temporarily overriding the means responsive to loss of the deviation signals during initial positioning of the vehicle with respect to the guidance conductor.
Claim 12
Dependent Claim
21 words
A system as claimed in claim 9, in which the overriding means includes means for temporarily disabling the steering control means.
Claim 13
Dependent Claim
12 words
A vehicle provided with a guidance system as claimed in claim 1.
Claim 14
Dependent Claim
15 words
A system as claimed in claim 1, including means operable to change said datum condition.
Claim 15
Independent Claim
87 words
A method of guiding a vehicle along a path defined by a guidance conductor, in which the deviation of the vehicle from the path is monitored and the steering mechanism of the vehicle is activated by a fixed amount about a datum condition in the appropriate direction for correcting the deviation when the deviation exceeds a predetermined level, the steering remaining activated by said fixed amount until the deviation is reduced below said predetermined level, the steering mechanism then being de-activated to return to the datum condition.
Claim 16
Independent Claim
87 words
A method of guiding a vehicle along a path defined by a guidance conductor, in which the deviation of the vehicle from the path is monitored and the steering mechanism of the vehicle is activated by a fixed amount about a datum condition in the appropriate direction for correcting the deviation when the deviation exceeds a predetermined level, the steering remaining activated by said fixed amount until the deviation is reduced below said predetermined level, the steering mechanism then being de-activated to return to the datum condition.
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1978-07-07 | 1979-01-06 | 1979-07-08 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1982-07-07 | 1983-01-06 | 1983-07-08 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1986-07-07 | 1987-01-06 | 1987-07-08 | $7700.00 | Window Closed / Lapsed |