1、ANSI/IEEE Std 293-1 969 (IEEE Reaffirmed June 19. 1986) Approved November 17, 1986 American National Standards Institute IEEE Test Procedure for Single-Degree-of-Freedom Spring-Restrained Rate Gyros Published by The Institute of Electrical and Electronics Engineers, Inc 345 East 47th Street, New Yor
2、k, NY 10017, USA ,A/O/(“/s) at (U,/ (b) Amplitude measurement method, Means of measuring the peak amplitude of the input rate, Means of measuring the in-phase component of the gyro output. 4.22.1.3 Test Setup and Procedure 4.22.1.3.1 Test Setup. Mount the gyro on the oscil- lating rate table with th
3、e gyro IRA aligned parallel to the axis of the table and nominally vertical. Operate the gyro in accordance with the standard test conditions of paragraph 3.1. Connect the gyro pickoff output and the table rate output to the phase measuring device. 4.22.1.3.2 Test Procedure 4.22.1.3.2.1 Natural Freq
4、uency. Apply a sinusoidal input of f _ O/s peak. Determine the input frequency f, at which the gyro output lags the input rate by 90 f _ degrees. 4.22.1.3.2.2 Damping Ratio. Apply a sinusoidal input rate of f O/s peak at frequencies of fJa, fJb, , f hertz where a, b, etc., are determined by the user
5、s requirements. Measure the phase relation between the gyro input and output or 4.22.1.4 Test Results 4.22.1.4.1 Natural Frequency. The natural frequency f. measured in paragraph 4.22.1.3.2.1 shall conform to the requirement of paragraph -. 4.22.1.4.2 Damping Ratio. The damping ratio is cal- culated
6、 from the data obtained in paragraph 4.22.1.3.2.2 -. by comparing the measured phase relationships with a phase angle-frequency plot for a damped second-order / k measure the peak amplitude of the gyro output. system or by comparing the measured amplitude ratios with an amplitude-frequency plot for
7、a damped second- order system. The damping ratio shall conform to the requirement of paragraph -. 4.22.2 Step Input Method 4.22.2.1 Purpose. The purpose of this test is to deter- mine the natural frequency and the damping ratio of the gyro by measuring its response to a step input. 4.22.2.2 Test Equ
8、ipment. The following test equipment from paragraph 3.2 is required for this test: Means of applying a step rate input to the gyro, Means of recording the gyro response to a step rate input. 4.22.2.3 Test Setup and Procedure. Mount the gyro on the step rate table with the gyro IRA aligned parallel t
9、o the axis of the table and nominally vertical. Operate the gyro in accordance with the standard test conditions of paragraph 3.1. Connect the gyro pickoff output and the table motion output to the recorder. Apply a change of rate from _ O/s to .- f - O/s during a period not to exceed _ seconds. Rec
10、ord the gyro and the table motion outputs. 4.22.2.4 Test Results. The gyro natural frequency and damping ratio are determined by comparing the recorded response with the step response of a damped second-order system. The natural frequency shall con- form to the requirement of paragraph -, and the da
11、mping ratio shall conform to the requirement of para- graph - 4.23 Warm-up Time Test 4.23.1 Purpose. The purpose of this test is to determine the time interval required for the gyro to reach specified performance from the instant that it is energized under specified operating conditions. 4.23.2 Test
12、 Equipment. The following test equipment from paragraph 3.2 is required for this test: Oscillating rate table (means of applying a sinusoidal rate to the gyro at a controlled frequency and am- plitude), Means of measuring the in-phase component of the gyro output, Means of measuring the elapsed time
13、. 4.23.3 Test Setup and Procedure. Mount the gyro on the oscillating rate table with the gyro IRA aligned parallel to the axis of the table and nominally vertical. Operate the gyro in accordance with the standard test conditions of paragraph 3.1 except that the thermal and mechanical starting condit
14、ions shall be and the energizing sequence shall be -. 13 14 00 NNN 0 COMMENTS SPECIAL TEST MAY BE RUN TO DETERMINE IF MOTOR REMAINS IN SYNC. CENTRIFUGE TESTS FOR ACCEL-SEWS. DRIFT USUALLY RUN WITH SPIN MOTOR-OFF. SPECIAL TEST MAY SE RUN TO OETERMlNE IF MOTOR REMAINS IN SYNC. SPECIAL TEST MAY BE RUN
15、TO DETERMINE IF MOTOR REMAINS IN SYNC. PARAMETRIC TESTS TO BE PERFOMEC AT INTERVALS TO BE SPECIFIED FOR EACH TEST. SPECl4L TEST MAY BE RUN TO DETERMINE IF MOTOR REMAINS IN SYNC. SPECIAL TESTS MAY BE ?UN TO DETERMINE IF MOTOR REMAINS IN SYNC. AN0 USING TORQUER TO DETERMINE RATE TRANSFER CHARACTCRISTI
16、CS. THE HAZARDS OF POST-EXPOSURE HANDLING SHOULD BE CONSIDERED. 15 Apply a sinusoidal input rate of f L_ O/s peak at a frequency of f hertz. Energize the gyro and simultaneously start the elapsed time re- corder. Measure the peak amplitude of the gyro output. When this output reaches - f O/s, stop t
17、he elapsed time recorder. 4.23.4 Test Results. The elapsed time measured shall conform to the requirement of paragraph -. 4.24 Environmental Test Series Procedures for most environmental tests are well covered by existing industry, government, and military documents, an example of which is MIL-E-527
18、2, “En- vironmental Testing, Acroiisutical and Associated Equip- ment,” Rather than duplicate samples of existing procedures, this Test Procedure provides assistance in selecting the gyro parameters that will be most im- portant to measure in each environment. This selection is made based on the exp
19、ected environmental sensitiv- ities of the spring-restrained single-degree-of-freedom rate gyro and the cost effectiveness of the testing. The application of the gyro will determine which tests, or combinations of tests, arc pertinent. 4.24.1 Purpose. The purpose of these tests is to verify that the
20、 gyro performs as specified during and/or after subjection to environments outside of the standard operating conditions, but within the specified environ- mental limits. 4.24.2 Test Equipment. The following test equipment from paragraph 3.2 is required for each environmental test: Equipment for prov
21、iding the specified environment, Means of measurement of the environment and time, Adaptation of the gyro to the environmental equipment such as special holding fixtures, cables, etc, Equipment for thc gyro test, chosen as indicated in paragraphs 4.1 through 4.22. 4.24.3 Test Procedure. Detail the p
22、rocedure for the manipulation of the environment, including the toleranccs and the rates of change, integrated with the procedure for the gyro test. Caution notes on overlosd limits on the environmental intensity applied to the gyro can be specified if required. 4.24.4 Test Results. Parametric test
23、data shall include the additional notation of the environment in which it was obtained. Where required, the gyro data shall be plotted versus the environmental intensity in order to determine the sensitivity. Table 1 is intended to be a guide for the selection of the gyro test that should be conduct
24、led in association with the environmental tests that are chosen dependent on the applicatiatl of the gyro. The coding is as follows: D = The gyro parametric test isR-to be conducted while the gyro is operating or nonoperating as applicable, during the specified environment. 0 = The gyro is to be ope
25、rated during the specified environment and the parametric test performed before and after. N = The gyro is to be nonoperating during the specified environment, and the parametric test performed before and after. S = A special test is recommexletl as described under Comments. When Monitor Output is the requirement, further clari- fication is necessary as to how output variation is to be judged. 16
