CONTROL SYSTEM FOR CONSTRUCTION MACHINES AND METHOD FOR OPERATING THE CONTROL SYSTEM

• US 20110153038A1
• Filed: 12/23/2010
• Published: 06/23/2011
• Est. Priority Date: 12/23/2009
• Status: Active Grant

• Current Assignee: Liebherr-Werk Ehingen GmbH (Liebherr-International AG)
• Original Assignee: Liebherr-Werk Ehingen GmbH (Liebherr-International AG)
• Inventors: ZINK, EDUARD, TREUER, JOACHIM, MORATH, ERWIN
• Granted Patent: US 8,649,943 B2
• Time in Patent Office: Days
• US Class Current: 700/73
• CPC Class Codes: G01L 19/0092 Pressure sensor associated with other sensors, e.g. for measuring acceleration or temperature G01L9/025, G01L9/045, G01L9/065, G01L9/085, G01L9/105, G01L9/125, G01L19/02, G01L19/04 take precedence; measuring two or more variable G01D21/02; temperature sensors with pressure compensation G01K1/26
• CPC Class Codes: G05B 9/03 with multiple-channel loop, i.e. redundant control systems

Abstract

A control system for a construction machine includes at least one sensor and at least one controller, wherein a serial connection exists between the sensor and the controller, and wherein at least one sensor and/or controller are of the two-channel or multi-channel type. Furthermore, this invention relates to a method for operating such control system for a construction machine.

Claims

1. A control system for a construction machine, comprising:

at least one sensor and at least one controller, wherein a serial connection exists between the sensor and the controller;

wherein said at least one sensor and said at least one controller are of the two-channel or multi-channel type;

each of said at least one sensor comprises at least two measured value pick-ups and at least two processing units which are arranged redundantly and/or diversely with respect to each other; and

said at least two processing units of the sensor are coupled with each other and a data connection exists between the processing units.

2. The control system for a construction machine according to claim 1, wherein each of said at least one sensor further comprises at least one secondary sensor selected from the group consisting of a temperature sensor, a pressure sensor and a combination thereof.

3. The control system for a construction machine according to claim 1, wherein said at least one controller comprises at least two control units arranged redundantly and/or diversely with respect to each other.

4. The control system for a construction machine according to claim 1, wherein the serial connection between said at least one sensor and said at least one controller is a bus system selected from the group consisting of a controller-area network (CAN) bus system, a Liebherr system bus, an Ethernet-based bus system and a combination thereof.

5. The control system for a construction machine according to claim 1, wherein said at least one sensor further includes a unit encrypting and packing the measured value to be transmitted, and said at least one controller further includes a unit for decrypting and unpacking the measured value.

6. The control system for a construction machine according to claim 1, wherein said at least one sensor detects a measurement parameter selected from the group consisting of pressure, angle, rotation, inclination, length, distance, sound, brightness, humidity, direction and filling level.

7. The control system for a construction machine according to claim 1, wherein said at least one sensor detects a measured value redundantly and/or diversely;

the measured value of said at least one sensor is filed in a data packet of a measurement protocol and provided with a safety and/or protection function by the sensor;

the data packet is transmitted to said at least one controller via the serial connection; and

said at least one controller checks the data packet or the measured value for correctness by the safety and/or protection function.

8. The control system according to claim 7, wherein, for each channel of said at least one sensor an individual sensor description is stored, which is cyclically scanned by the controller, and an individual key is calculated from the sensor description by an algorithm.

9. The control system according to claim 7, wherein said at least one controller cyclically initiates a status inquiry for each sensor and in response each sensor transmits its sensor status description to the inquiring controller via a bus system.

10. The control system according to claim 7, wherein the controller requests the measured value of said at least one sensor by the measurement protocol.

11. The control system according to claim 8, wherein, for verification of the transmitted data packets of the measured values and the sensor status description, the individual key is used.

12. The control system according to claim 7, wherein said at least one controller comprises at least two control units, and one control unit of the controller receives the data of said at least one sensor via the bus system and forwards copies of the data to all the other control units of the controller.

13. The control system according to claim 12, wherein each control unit verifies the received sensor data or the data copies by the safety and/or protection function.

14. A control system for a construction machine, comprising:

at least one sensor comprising;

a sensor housing having a specimen feed to receive a medium to be detected;

a first measured value pick-up housed in the sensor housing, the first measured value pick-up measuring a variable to obtain a first measured value;

a second measured value pick-up housed in the sensor housing, the second measured value pick-up measuring a variable to transmit a second measured value, the first and second measured value pick-ups mounted in the specimen feed to be spaced apart from each other with a substantial identical distance from an entry of the specimen feed;

a first processing unit having a first input receiving the first measured value from the first measured value pick-up and a first output; and

a second processing unit having a second input receiving the second measured value from the second measured value pick-up and a second output, the first and second processing units coupled to each other via a signal connection to communicate the first and second measured value pick-ups;

wherein at least one of the first processing unit and the second processing unit has a comparing unit to compare the first measured value with the second measured value, the first processing unit and the second processing unit store one of the first and second measured value in the first output and the second output when a deviation of the compared first and second measured values is within a preset tolerance limit, and mark one of the first and second measured value as faulty and store the marked value from the first or second output when a deviation of the compared first and second measured values is not within the preset tolerance limit; and

at least one controller serially connected to said at least one sensor, said at least one controller comprising;

a first control unit receiving data from the first and second outputs of the first and second processing units and verifying the data, the first control unit forwarding the data to the second control unit; and

the second control unit receiving the data from the first control unit to verify the data.

15. The control system for the construction machine according to claim 14, wherein the serial connection between said at least one sensor and said at least one controller is a bus system selected from the group consisting of a controller-area network (CAN) bus system, a Liebherr system bus, an Ethernet-based bus system and a combination thereof.

16. The control system for the construction machine according to claim 14, wherein said at least one sensor further includes a unit encrypting and packing the measured value to be transmitted, and at least one of the first and second control units of the controller further includes a unit for decrypting and unpacking the measured value.

17. The control system for the construction machine according to claim 14, wherein said at least one sensor detects a measurement parameter selected from the group consisting of pressure, angle, rotation, inclination, length, distance, sound, brightness, humidity, direction and filling level.

18. The control system for a construction machine according to claim 14, wherein the measured value of said at least one sensor is filed in a data packet of a measurement protocol and provided with a safety and/or protection function by the sensor;

the data packet is transmitted to said at least one controller via the serial connection; and

said at least one controller checks the data packet or the measured value for correctness by the safety and/or protection function.

19. A control system for a construction machine, comprising:

at least one sensor comprising;

a sensor housing having a specimen feed to receive a medium to be detected;

a first measured value pick-up housed in the sensor housing, the first measured value pick-up measuring a variable to obtain a first measured value;

a second measured value pick-up housed in the sensor housing, the second measured value pick-up measuring a variable to obtain a second measured value, the first and second measured value pick-ups mounted in the specimen feed to be spaced apart from each other with a substantial identical distance from an entry of the specimen feed;

a first processing unit having a first input receiving the first measured value from the first measured value pick-up and a first output; and

a second processing unit having a second input receiving the second measured value from the second measured value pick-up and a second output, the first and second processing units coupled to each other via a signal connection to communicate the first and second measured value pick-ups;

wherein at least one of the first processing unit and the second processing unit has a comparing unit to compare the first measured value with the second measured value, the first processing unit and the second processing unit store one of the first and second measured value in the first output and the second output when a deviation of the compared first and second measured values is within a preset tolerance limit, and mark one of the first and second measured value as faulty and store and output the marked value from the first or second output when a deviation of the compared first and second measured values is not within the preset tolerance limit; and

at least one controller serially connected to said at least one sensor, said at least one controller comprising;

a first control unit receiving data from the first and second outputs of the first and second processing units and verifying the data, the first control unit forwarding the data to the second control unit; and

the second control unit receiving the data to verify the data;

wherein said at least one controller requests cyclically a sensor status and the sensor transmits its sensor status description in a data packet to the inquiring controller, and the sensor status description is determined internally in each processing unit of the sensor; and

said at least one controller checks the data packet or the measured value for correctness by the safety and/or protection function.