Obstacle detection method and system, particularly for systems for assisting the parking of vehicles

• US 20060087415A1
• Filed: 09/15/2005
• Published: 04/27/2006
• Est. Priority Date: 09/24/2004
• Status: Active Grant

• Current Assignee: META Systems (Siemens AG)
• Original Assignee: META Systems (Siemens AG)
• Inventors: Simonazzi, Giuseppe
• Granted Patent: US 7,358,850 B2
• Time in Patent Office: Days
• US Class Current: 340/435
• CPC Class Codes: G01S 15/931 of land vehicles
• CPC Class Codes: G01S 2015/932 for parking operations

Abstract

An obstacle detection method and system, particularly for car parking systems comprising emitting ultrasound signals at a plurality of sensors, receiving echo signals returned by at least one obstacle, performing a parametric evaluation of the received signals, determining, for each sensor, the distance between the sensor and an obstacle detected by it, associating with each sensor a value of the distance from the obstacle detected by it; determining a value corresponding to the minimum detected distance and replacing it with the sum value between a minimum distance and a priority threshold value; assigning to the sensor that detected the minimum distance a priority status; and defining a sensor polling cycle that polls more frequently a priority status sensor than non-prioritized sensors.

Claims

1. An obstacle detection system, comprising:

a control unit;

a plurality of sensors, and electronic-processing means provided at said control unit for driving cyclically said sensors according to an order of priority.

2. The obstacle detection system of claim 1, comprising at least one bus, said sensors being connected to said control unit by way of a single said bus.

3. The obstacle detection system of claim 1, wherein said sensors comprise emission means for emitting an ultrasound signal and for receiving an echo signal returned by at least one obstacle.

4. The obstacle detection system of claim 3, wherein said sensors comprise parametric evaluation means for parametric evaluation of said echo signals.

5. The obstacle detection system of claim 4, wherein said parametric evaluation means are suitable to determine values detected by said plurality of sensors, which indicate, for each sensor, a distance between said sensor and an obstacle detected by the sensor.

6. The obstacle detection system of claim 5, wherein said control unit comprises memory means for storing said values that indicate the distance between the sensors and the obstacle.

7. The obstacle detection system of claim 5, wherein the order of priority for management of said plurality of sensors is determined according to said values that indicate the distance between said sensors and the obstacle.

8. The obstacle detection system of claim 5, wherein said parametric evaluation means comprise power driving means suitable to drive power radiated by said signal emission means.

9. The obstacle detection system of claim 8, wherein said parametric evaluation means comprise comparator means suitable to compare said echo signals received from said emission means with threshold values.

10. The obstacle detection system of claim 9, wherein said parametric evaluation means comprise cycle determination means suitable to determine, at each sensing cycle, a number of cycles in which received signals are repeated and to send to said control unit only signals that are repeated for a number of cycles that is greater than a preset number of cycles.

11. An obstacle detection method, comprising the steps of:

a) providing emission of ultrasound signals at a plurality of sensors;

b) providing reception of echo signals returned by at least one obstacle and performing a parametric evaluation of received signals, and determining, for each sensor, a distance from the sensor to an obstacle detected by the sensor;

c) associating with each sensor a value of the distance from the obstacle detected by the sensor;

d) determining a value that corresponds to a minimum detected distance and replacing the value with a further value equal to a sum of said minimum distance value and a priority threshold value;

e) assigning to a sensor that detected said minimum distance a priority status; and

f) defining a cycle for polling the sensors, which polls more frequently a sensor that has a priority status with respect to sensors that do not have a priority status.

12. The obstacle detection method of claim 11, further comprising the steps of:

g) updating, at each polling cycle, distances from the obstacles detected by the sensors;

h) determining whether at least one of the detected distances is shorter than the sum of the minimum distance value and the priority threshold value;

i) assigning to a respective sensor a priority status in addition to sensors that already have priority status; and

j) redefining a polling cycle so as to poll more frequently sensors that have a priority status with respect to sensors that do not have a priority status.

13. The obstacle detection method of claim 12, wherein during the polling cycle the sensors that failed to detect an echo signal are excluded for a preset number of cycles greater than zero.