Frequency response measurement software
OS-4100 New

Motors and drivers incorporated in various products such as robots, conveyance equipment, semiconductor manufacturing machines, and automobiles have control circuits built in to control their rotational speed and torque. As the stability evaluation of control characteristic, there are gain margin and phase margin measurements.The OS-4100 can automatically calculate gain margin and phase margin from frequency response function (open loop transfer function).
It can obtain the open loop transfer function by measuring the closed loop transfer function. The DS-0545 2ch Signal Output Unit outputs the signal that the signal generated from the DS is added to the feedback signal from the object, which makes it possible to directly input signals to the control circuit and easily evaluate the stability of the control circuit. In addition, by using the step response function it measures and automatically calculates responsiveness (delay time, overshoot value, etc.) in the time domain.

The performance of the object can be obtained from the temporal response. By applying step signals to the object and measuring the step response signals, it automatically calculates the values related to response performance (rising time, etc.) and compares actual measurement data with past data.

(Cooperation: Citizen Chiba Precision Co., Ltd.)

The Galvanoscanner is equipped with a motor to adjust the scanning angle of the mirror that reflects the laser beam and a high-precision position sensor. It is used in a wide range of applications in combination with laser beam, such as laser markers, microscopes, and LiDAR, and is required to scan mirrors over a wide range at high speed and with high precision. When developing products, it is necessary to perform highly accurate simulations to achieve high speeds and optimize models and control parameters. In addition, in order for customers to use products with peace of mind, it is required to confirm that the product's performance is guaranteed before shipping. Therefore, it was a challenge to easily measure and understand the control characteristics of the Galvanoscanner and the mirror's resonant frequency with high precision.

2-1. Evaluation of galvanoscanner control characteristics
Results of comparing three types of control parameters

2-2. Measurement of mirror resonance
Comparison of three types of mirrors

Please see the related pages below.

Application example: Evaluation of galvanoscanner control characteristics
Customer Reviews: Application example in control characteristic evaluation

When vibration is applied to a structure, if that vibration frequency is equal or close to the structure's natural frequency, resonance will occur, resulting in extremely large vibrations that may lead to failure or destruction. Therefore, it is important to evaluate the vibration characteristics of structures. The OS-4100 can simultaneously measure up to 42 channels of vibration characteristics using an exciter.
It can convert acceleration to displacement by the calculus function, control the amplitude value of excitation by the amplitude control function, and measure the characteristics after subtracting the weight of the jig (mass cancellation) by the four arithmetic operations (Calculation between items).

Image of measurement results

The amplitude of the exciter can be controlled. The amplitude of the signal output (DS-5000) can be automatically adjusted so that the measured amplitude becomes the preset amplitude. Vibration characteristics can be measured without being affected by jig vibration characteristics. In addition, the amplitude (displacement) can be controlled with an accelerometer.

Output Amplitude Control function　Setting display

Example of Amplitude control measurement

One of method for evaluating batteries is the AC impedance method. This method enables to evaluate battery resistance characteristics (deterioration of electrodes, etc.) without destroying or disassembling the battery. The AC impedance can be measured by applying an AC current load to the battery and measuring the voltage and current of the battery.
By adopting the FRA method, it is possible to measure with high accuracy and high frequency resolution in a wide dynamic range. It can display with a Cole-Cole plot, which is useful for estimating the cause of battery deterioration. uff file or HDF5 format is available for easy transfer of measurement results to simulation software.
* An electronic load device and a current probe are required for this measurement.

Image of measurement results

A Cole-Cole plot is a graph that shows the real part of the frequency response function on the horizontal axis and the imaginary part on the vertical axis.
It is useful to examine an equivalent circuit.

Frequency range division setting

The setting can be changed for each frequency to be measured.　It can shorten the measurement time to measure only important frequency bands with high frequency resolution or measure bands with few variation roughly. In addition, by changing the amplitude of the signal output for each frequency band, optimal measurement can be performed to improve S/N.

Sound frequency characteristics is one of the factors that evaluate speaker performance. By connecting the signal output from the DS-5000 to the speaker amplifier and capturing the sound generated from the speaker with a sound level meter or microphone, the OS-4100 measures the frequency characteristics of the speaker. Also, the function (cutoff search function) which finds a cutoff frequency automatically is equipped.

Image of measurement results

FFT method

FRA method

When evaluating the characteristics of electrical systems such as filters and amplifiers, the OS-4100 enables to measure frequency characteristics with high resolution. It also has a function to automatically search for a frequency to cutoff.