Random-on-random（RoR）control simulates real-world complex vibration environments with a combination of a broadband random signal and one or more superimposed random narrow-bands。Both signal types are usually present simultaneously and the narrow-bands can appear at fixed frequencies or sweep over a predefined range.The overall random PSD（power spectral density）shifts with time or is related to a variable-speed device。
In RoR，a more complex function of the basic random control profile，all resonant frequencies of any given payload are excited at once；thus，it is well suited for product qualification and fatigue tests.Atypical example is the repetitive stress on a truck’s headlights，as the vehicle changes speed hiroghteron。
USE SCENARIOS
- 配电支座支座支座支座支座支座支座支座支座支座支座支座支座支座支座支座支座支座支座支座支座支座支座支座支座
- 列车动力测试装置
- 测试端对端对端对端对端对端对端对端，对端对端对端，对端对端
- 测试边距测量仪，such as propeller-driven aircraft
CHARACTERISTICS
In this type of test profile，the broadband signal also consists of auser-specified breakpoint table of PSD versus frequency.Typically，up to 12narrow-band signals can be concurrently generated，where each band has independently set PSD amplitude， frequency-sweep range and rate.Narrow-bands can be configured both at user-specified fixed frequencies or in sweeping mode。
Slopes and crossover points are automatically calculated by the control algorithm.There is usually a choice to sum the narrow-band and broadband or to use the largest PSD value from the profile.This allows the swept narrow-band to either dominate on a broadband slope or to be reduced where the broadband。
There usually is a harmonic mode，whereby subsequent narrow-bands are configured using integer multiples of the first narrow-band’s frequency parameters。
RoR control contains all of the automatic and manual test controls that are available in the random profile feature.A PSD amplitude versus frequency sweep envelope for narrow-bands is typically included，providing a pre-test validation of the configuration.During tests， individual narrow-bands and the broadband can usually be turned on and off manually，orautomatically according to a pre-defined timetable。
