Apparatus for and method of testing hydraulic/pneumatic apparatus using computer controlled test equipment

• US 5,337,262 A
• Filed: 12/03/1991
• Issued: 08/09/1994
• Est. Priority Date: 12/03/1991
• Status: Expired due to Term

• Current Assignee: Textron Innovations Incorporated (Textron Inc)
• Original Assignee: HR Textron, Inc.
• Inventors: Tauber, Richard, Luthi, Jeffrey L.
• Primary Examiner(s): Harvey, Jack B.
• Assistant Examiner(s): Wachsman, Hal D.
• Application Number:
  US07/801,242
• Time in Patent Office: 980 Days
• Field of Search: 73/168, 73/4 R, 73/11, 73/11.01-11.09, 73/40, 364/424.03, 364/424.04, 364/580, 364/483, 364/558, 364/550, 324/73.1, 371/22.1, 371/26
• US Class Current: 702/83
• CPC Class Codes: F15B 19/00 Testing; Calibrating; Fault detection or monitoring; Simulation or modelling of fluid-pressure systems or apparatus not otherwise provided for

Abstract

Automatic test equipment for testing hydraulic/pneumatic devices which devices are included within the test system as well as those which may be attached to the test system. Object oriented programming preferably using C++ language is utilized. Abstract classes representative of characteristics of a group of devices to be tested are provided. Also provided are subclasses characteristic of types of units to be tested. Upon declaration of a specific instance of a type of unit to be tested, the abstract class is inherited into a subclass which in turn is incorporated into the unique characteristics for the declared unit to be tested. A test program is activated for the specific unit to be tested. The test program is also constructed by utilizing abstract and subclasses of information characteristic to the unit to be tested. As the test is being conducted, additional tests or devices within the system are addressed to permit utilization of the information so addressed or alternatively, communication with devices contained within the test system as required for conducting and completing the test on the unit under test.

Claims

1. A method for automatically testing electrohydraulic/pneumatic hardware comprising:

(A) providing an abstract base class defining a plurality of characteristic data and functions common to all of a plurality of predetermined units to be tested;

(B) providing at least one subclass defining a plurality of characteristic data and functions specific to a predetermined type of unit to be tested but not all of such units;

(C) defining specific characteristic data and functions unique to a specific unit of said type of unit;

(D) declaring said specific unit of said type of unit for testing (UUT);

(E) inheriting into said specific characteristic data and functions said plurality of characteristic data and functions from said abstract base class;

(F) inheriting into said specific characteristic data and functions said plurality of characteristic data and functions from said at least one subclass;

(G) activating a test program for said declared UUT;

(H) measuring the results of said test program;

(I) comparing said results of said test programs with said specific and inherited at least one subclass and abstract base class characteristic data and functions; and

(J) reporting whether said UUT test results fall within said specific and inherited at least one subclass and abstract base class characteristic data and functions.

2. A method as defined in claim 1 wherein said test program includes a base class test program defining a plurality of test steps common to all UUT devices of the type including the declared UUT and a specific class test program defining a plurality of test steps unique to said declared UUT, and inheriting said common test steps into said unique test steps for testing said declared UUT.

3. A method as defined in claim 2 which further includes the step of deactivating said test program upon completion of said test program on said declared UUT.

4. A method as defined in claim 2 wherein at least one of said plurality of test steps points to and incorporates a further test step applicable to said declared UUT.

5. A method as defined in claim 2 which further includes the steps of isolating a test step wherein a failure has occurred and performing a diagnostic test to ascertain the probable cause of said failure.

6. A method as defined in claim 5 which further includes the step of printing the results of said diagnostic test.

7. A method as defined in claim 1 which further includes the steps of:

(A) providing a hydraulic console;

(B) providing an electronic console;

(C) interconnecting said electronic and hydraulic console;

(D) attaching said UUT to said hydraulic console; and

(E) activating selected portions of said electronic and hydraulic consoles for performing said test program on said UUT.

8. A method as defined in claim 1 wherein said specific characteristics unique to a specific unit define data and functions which are descriptive of said declared UUT.

9. A method as defined in claim 8 wherein said declared UUT is a device contained within a test system.

10. A method as defined in claim 8 wherein said declared UUT is a device external to a test system.

11. Apparatus for automatically testing hydraulic/pneumatic devices comprising:

(A) a hydraulic/pneumatic console;

(B) an electronic control console;

(C) means for interconnecting said hydraulic/pneumatic console and said electronic control console;

(D) said electronic control console including digital computer means having memory means;

(E) first means for storing in said memory means an abstract base class defining a plurality of characteristic data and functions common to each of a plurality of predetermined units to be tested;

(F) second means for storing in said memory means at least one subclass defining a plurality of characteristic data and functions specific to a predetermined type of unit to be tested;

(G) means in said computer for combining said abstract base class and said at least one subclass to define a specific unit to be tested;

(H) third means in said memory means for storing a test program applicable to said specific unit to be tested;

(I) means for removably attaching a unit to be tested to said hydraulic/pneumatic console;

(J) means for activating said test program to test said specific unit to be tested; and

(K) means for indicating the results of said test program on said specific unit to be tested.

12. Apparatus as defined in claim 11 wherein said electronic control console includes circuit means for testing feedback in a unit to be tested, said circuit means including a plurality of different feedback circuit means, a command circuit for applying a command signal to said unit to be tested, means for enabling selected feedback circuit means, and summing means for incorporating signals in said enabled selected feedback circuit means into said command signal.

13. Apparatus as defined in claim 12 wherein said feedback circuit means includes an Linear Variable Differential Transformer (LVDT) feedback circuit.

14. Apparatus as defined in claim 12 wherein said feedback circuit means includes a linear encoder.