Vibration/Bump/Shock Test Systems

HomeVibration/Bump/Shock Test Systems

Electro-Dynamic Shakers

DESPL manufacturers and supplies a wide range of vibration test systems that are both cost effective and easy to use. These tools empower the maintenance professionals to detect and evaluate machine vibrations easily.

DESPL are capable of offering an array of customerised solutions that can meet customer’s every need and requirement. Using high-tech technologies, they supply vibration test tools that are eco-friendly and produce low noise. The eco-technology enables you to reduce carbon emissions and electricity consumption.

The range of Vibration Test Systems includes the following models:

Product Range:

  • Equipment
  • USB Vibration Controller
  • Vibration Test Machine
  • Digita Switching Power Amplifier
  • Shock Vibration Test Test Systems
  • Head Expanders
  • Slip Tables
  • Vertical Load Supports

Shock Systems

The Free Fall Shock system is designed to produce classical shock wave shapes by dropping a platform supported on rods and bearings. The platform drop height is pre-adjustable for shock pulse repeatability. Peak Acceleration levels are based on the drop height while time duration is a function of the programprovided, elastomer pads for half-sine, lead pellets for saw-tooth and pneumatic cylinders for square and trapezoidal wave pulses.

Each system is supplied with brakes to prevent repeated impacts and incorporates a heavy steel reaction mass mounted on springs with isolators/dampers to isolate the shock from the floor and which will not deteriorate under repeated bumps. The structure is supported on four passive air springs to isolate the bump pulses from the floor as it is designed for very high ‘g’.

The test item shall be mounted to a solid AI/MS carriage with steel inserts on the top surface. The platform is supported and guided by the lifting and driving piston rods.

The PC based hardware and software is used for transfer, storing, retrieval and generating graphs/waveforms. Computer compatible for the control of the bump test system like pneumatics, falling of platform and hydraulic brakes is be provided.

Technical Specifications
Pay Load CapacityUp to 1000 Kgs
Table Size of the unit under testAs per customer requirements (Maximum: 1500 mm x 1500 mm)
Test Pulses (ms)Half-sine, 3ms, 9ms, 11ms,15ms, 18ms, 20ms, 30ms, 40ms

(Required pads shall be provided)

 

“g” value10 ‘g’ to 500 ‘g’ Settable (Tolerance ±10%)
Shock Rate1-10 shocks per minute (settable)
Shock Test Systems DetailsComplete details of system with respect to principle of operation, construction of the bump system including the major sub-systems like mounting provision for the unit under test. All accessories required to perform the tests shall be clearly indicated by the end user.
Control SystemsState of the art controlling and programming/setting of the following parameters shall be provided with digital and graphical indication.

 

Height, No of shocks with an elapsed counter. Digital and graphical indication of the waveform, “g” values and pulse width.

 

System Features:

  • PC Based Control
  • Table Extender
  • Custom Hole Pattern
  • Mounting Test Fixtures
  • Monitoring Instruments

Bump Systems

The Bump system is used to test the integrity and rigidity of objects under the simulation of various road/field transport conditions.

The Bump system incorporates a rigid steel structure to sustain the force of up to 1000 kg for a half sine.

The mounting platform lifts vertically up to the desired impact acceleration through a cam arrangement and drops freely onto the rubber pads which gives the desired pulse shape.

The desired acceleration depends on the free fall height of the platform which is factory set. The duration of the half sine pulse shape depends on the hardness and thickness of the rubber pads.

The mounting platform has a grid pattern of 100 mm x 100 mm threaded M10/M12 holes to mount the device under test.

An AC motor along with a speed reducer gearbox are used to achieve the desired bump rate of 1 to 3 bumps per second. The three-phase motor also incorporates safety protection in the form of Over Load, Under Voltage and Over Current protection.

The PC based hardware and software is used for transfer, storing, retrieval and generating graphs/waveforms. 

Technical Specifications
Pay Load CapacityUp to 2,000 Kgs
Table Size As per customer requirements (Maximum: 1500 mm x 1500 mm)
Bump RateAdjustable 1 to 3 bumps / sec
Bump Rate CounterDigital
AccelerationUp to 100 ‘g’ (±10%)
Pulse ShapeHalf-sine
Pulse DurationAdjustable 2 to 18 milliseconds (±10%)
Control PanelPreset mechanism with on off switch
CalibrationTraceabe calibration certificate will be provided
Mains Supply415V±10% AC, 50 Hz, 3 Phase

System Features:

  • PC Based Control
  • Monitoring Instruments
  • Complies with various international standards

Centrifuge Test Systems

 

Centrifuge Acceleration test systems (also known as a linear acceleration test system) are used to subject a test object to a defined force. A predefined centrifugal force is exerted on a test object when it is placed inside a rotary platform at a certain radial distance.

Centrifugal test systems are used to analyze the mechanical behavior of various components and assemblies,when subjected to linear acceleration. It is widely used in the avionics and military hardware testing, satellite component testing, R&D laboratories, system qualification testing, product and reliability development, stress screening, etc. Centrifuge tests are performed in accordance with the relevant ISO, IEC, JSS 55555, MIL-STD and other international standards.

The centrifuge test system has a robust structure that consists of an outer enclosure from a safety point of view to withstand centrifugal forces acting on the test object. It consists of a rotating platform which can accommodate a wide variety of payloads in various sizes and loads at a required radial distance from the centre to achieve the desired acceleration.

The system is driven by AC/DC drive motors and the speed is varied by the IGBT based PWM type AC/DC drive with instrumentation system having built in digital closed loop control.

Electrical/electronic data transfer connections are available through various terminals for actual working conditions and test environments.

The overall structure is made from heavy gauge mild steel. The lower half of the structure consists of a hollow cabinet containing the DC motor and the vertical rotating shaft. The upper half is an octagon shape where the rectangular platform is coupled to the top end of the vertical shaft.

 

ParametersModels
DCFG-50-30DCFG-100-70DCFG-100-75DCFG-200-125DCFG-20,000-13DCFG-40,000-10DCFG-80,000-10
Acceleration range1-50 ‘g’1-100 ‘g’1-100 ‘g’1-200 ‘g’500-20,000 ‘g’500-40,000 ‘g’500-80,000 ‘g’
Nominal Radius300 mm700 mm750 mm1250 mm130 mm80 to 100 mm80 to 100 mm
Platform Radius Range250-350 mm500-900 mm550-950 mm750-1750 mm
Payload Size100 mm3400 mm3400 mm31000 mm3
Payload Capacity50 kg50 kg100 kg250 kg1 kg0.5 kg0.4 kg
Test Directionx, y, zx, y, zx, y, zx, y, zx, y, z

(6 directions)

x, y, z

(6 directions)

x, y, z

(6 directions)

Max Speed550 rpm350 rpm350 rpm400 rpm1200 rpm19,000 rpm27,000 rpm
Speed Resolution0.5 rpm0.5 rpm0.5 rpm0.5 rpm5%5%5%
Dimensions

(approx.)

Dia: 800 mm

Height: 800 mm

Dia: 2,000 mm

Height: 2,000 mm

Dia: 2,000 mm

Height: 2,000 mm

Dia: 3,600 mm

Height: 2,000 mm

800 mm x 800 mm x 850 mm
Weight

(approx.)

1,500 kg2,500 kg3,000 kg5,000 kg2,400 kg1,800 kg1,800 kg
Online Connections

(Through slip rings)

Electrical, Electronic, Data transfer, RF, Pneumatic, Hydraulic connections are available
Utilities Required415V ±10%, 3 phase, 50 Hz AC
Safety InterlocksMains input, over and under voltage, phase fail, door lock, imbalance vibration

 

Vibration controller

 

Vibration controller is suitable for both electro-dynamic and servo-hydaulic shakers, it drives shaker to simulate the realistic vibrations under laboratory environment. It is a full featured controller, making it possible for users to take all kinds of testing to eliminate the destructive effects for products that caused by vibrations.

Superb Performance and Reliability

It features superior performance in both R&D and production environments. It is designed based on distributed processing structure with multi-DSPs technology, low noise hardware design, 32-bit float point digital filtering, 24-bit ADC/DAC resolution, and advanced adaptive control algorithms. Its real PC-independent structure ensures that all commands bring immediate control response without degrading the performance of the testing system. DSP controlled digital synthesis and filtering provides fast loop times for quick test load equalization and enhanced safety.

Powerful Versatility and compatibility

This controller supplies powerful compatibility to electro-dynamic shakers. And it offers a comprehensive and flexible suite of control software packages with compliance of different operating system. You can customize your own test application without expensive hardware upgrades, change of your computer and operating system. This also serves engineers flexible multi-users supervision and management.

Maximized Convenience

Its powerful automation wizard makes repetitive and boring tasks simple, allowing you to run complex tests with a single keystroke. Its setup wizard and user-friendly graphical interface simplify setup for coordinated environmental testing and reduce test time. Also “One-click” automatic report generation eliminates the tedium of creating test documentations.

USB2.0 Connectivity

Adopted USB2.0 connectivity with superior speed and convenience. When you connect controller to your computer, it will be identified as a true USB2.0 device. You will enjoy this connectivity by easy plug and play, high speed and easy to use.

Enhanced test Safety

Safety checks and interlocks ensure the safety of the personnel, test article, and shaker, such as automatic detection of input overload, open loop and loss of signal, etc. Moreover, you can use a built-in hardware “ABORT” button to stop the test in case of emergency.

 

Specification

  • Up to 64 synchronized input channels
  • 24-bit ADC/DAC resolution
  • 32-bit floating-point DSP computation
  • Charge, Voltage, ICP, TEDS (Optional)
  • 100dB control dynamic range
  • Up to 3200 lines resolution in random(6400 lines optional)

AC Power – 88-264V, 47-53Hz Auto sensing.
Operating Temperature – 0 to 50°C.
Humidity – 20 to 90% RH.

PC Connection

Operating System – Win 2000/NT/XP/Vista/Win 7.
Connectivity – USB 2.0/3.0.

Features

  • Distributed Processing Architecture
  • High Reliability and Real-time
  • Expandable: Inputs • COLA • Digital I/O
  • Compatible with Electro-dynamic shakers
  • Hardware and software abort assurance
  • Enhanced Test Safety
  • USB Connectivity
  • Test automation
  • Direct Voltage • ICP • TEDS sensors connectivity
  • Windows/Linux Operating System Support
  • Kurtosis control
  • Data Export

Control Applications Available Include

  • Sine(Sweep & Dwell)
  • Random
  • Resonance Search Track & Dwell (RSTD)
  • Classical Shock
  • Sine on Random(SoR)
  • Optional – Random on Random (RoR), Sine and Random on Random (SRoR)

Hardware Inputs

  • Analog channels – 4,8,16,32 or 64 synchronized
  • Resolution – 24-bit, ADC
  • Voltage ranges – ±10, ±1 or ±0.1 VPK
  • Filtering – Anti-aliasing analog filtering 160 db/oct digital filtering
  • Coupling – Voltage, ICP standard TEDS (optional)
  • Sampling rate – 51.2 KHz
  • Maximum input – ±36VPk
  • Dynamic range – 120 dB
  • Amplitude accuracy – within 0.01DB
  • SNR – > 100 DB

Hardware Outputs

  • Analog channels – One Drive Channel, One COLA (optional)
  • Resolution – 24-bit, DAC
  • Voltage ranges – ±10V Pk
  • Filtering – Anti-aliasing analog filtering 160 dB/oct digital filtering
  • Dynamic range – 110 DB
  • THD – < 100 DB

 

Software

Random

Random performs fast, accurate and real time multi-channel closed loop control of PSD profiles. Based on advanced adaptive control algorithm, the system responses the change of the non-linear character, resonance frequency and loading quickly and precisely.

Specifications

  • Test Mode True Gaussian
  • Frequency range 1Hz to 5000 Hz
  • Resolution 100, 200, 400, 800, 1600, 3200 lines and 6400(optional)
  • Control Dynamic range > 90 dB
  • Loop time typical 80ms
  • DOF 2 to 1000
  • Control accuracy – ±1dB at 99% confidence within 200 DOFs
  • Control strategies – Single Channel, Weighted Average, Minimum, and Maximum

Sine

Sine performs closed loop control of sine vibration. The advanced adaptive control algorithm provides time and frequency calculations using floating point math calculations, resulting in frequency changes as small as 1 millionth of a Hertz to produce a smooth and continuous sweep.

Specifications

  • Frequency range 1Hz to 5,000 Hz, extendable to 0.01Hz downwards
  • Dynamic range up to 95 DB
  • Loop time: Typically, 5 ms
  • Control accuracy ±1DB at 1 octave/min
  • Compression rate Adaptive or fixed 0.3 to 3,000 dB/sec
  • Control strategy Single Channel, Weighted Average, Minimum, Maximum
  • Sweep type and rate- Linear – 0 to 6,000 Hz/min or logarithmic – 0 to 100 octave/min.
  • Sine dwell: User specified dwell frequency with duration in cycles or time.

Resonance Search Track & Dwell (RSTD)

  • Automatic resonance search
  • Dwell while searching or dwell after searching based on dwell list
  • Dwell list is user programmable
  • True cycle counting

Step Sine

  • Step/Discrete sine

Classical Shock

Classical Shock performs fast, accurate and real time multi channel closed loop control of transient waveforms. The entire transient period is sampled simultaneous and gap free. Based on advanced transfer function adaptive control algorithm, the system responses the change of the non linear character, resonance frequency and loading quickly and precisely.

Specifications :

  • Advanced adaptive control algorithm based on transfer function
  • High precision Low-pass Filtering
  • 05 to 100,000 ms pulse duration
  • 90 dB Dynamic range
  • Up to 16384 points data size
  • Versatile pulse waveforms
  • ISO/MIL-STD-810/user defined standard for tolerance setup
  • Flexible compensation methods

Shock Pulse

  1. Classical Pulse types: Half-sine, Haversine, initial and terminal peak saw tooth, triangle, Rectangle and trapezoid.
  2. Inverting: Pulses can be inverted in shape.
  3. Pulse Compensation: Pre and post-pulse, post-pulse only, or pre-pulse only; single or double sides for minimum acceleration and fully use of shaker stroke.
  1. Pulse delay: User specified in seconds.
  2. Profile View: Profile graphics shown and updated as profile is created. Profile operating levels are compared to the shaker parameter table.
  3. Criterion: ISO, MIL-STD-810, User defined

Sine on Random

SoR performs fast, accurate and real time multi-channel closed loop control of PSD profiles. Sine tones can be added on broad base Random, while sine can be fixed or sweep type. Based on advanced adaptive control algorithm, the system responses the change of the non-linear character, resonance frequency and loading quickly and precisely.

Specifications

  • Analog sine sweeps on wide band Gaussian random distribution
  • Up to 12 sine tones
  • Independent profile for each tone
  • Sine tone burst on and off, Independent time configuration
  • Parameters in each tone are all user programmable./li>

Random on Random

RoR performs fast, accurate and real time multi-channel closed loop control of PSD profiles. Narrow band Random profile can be added on broad base Random. Based on advanced adaptive control algorithm, the system responses the change of the non-linear character, resonance frequency and loading quickly and precisely.

Specifications

  • Narrow band Gaussian random sweeps on wide band Gaussian random distribution
  • Up to 12 narrow bands
  • Independent profile for each band
  • Parameters in each band are all user programmable.

Road Simulation/Long time history (LTH)

Specifications

  • Hours duration for simulation
  • Control strategy: time domain profile controlling based on FRF
  • Data formats: ASCII delimited format(Y only or X-Y pairs), ASCII UFF, Binary
  • Data re-sampling: from 20 to48,000 samples in 24 stages.
  • Pre-stored profiles: band-limited random, white noise, sine and chirp
  • Compensation: high-pass, low-pass, velocity DC removal, acceleration DC removal
  • Profile rescale: magnitude or polarity adjustment by applying a profile scale factor to each data point of the profile
  • Real-time and high fidelity drive generation
  • Convenient profile generation and editing

Seismic Simulation/Transient Time History (TTH)

Specifications

  • Seismic or crash test
  • Data formats: ASCII delimited format(Y only or X-Y pairs), ASCII UFF, ECON Binary
  • Data re-sampling: from 20Hz to 48,000Hz in 24 stages.
  • 256, 512, 1024, 4098, 8192, 16384 frame points
  • Bellcore Z1 and Z2, Bellcore Z3, Bellcore Z4 and Sine, Chirp, White Noise

Horizontal Slip Table

Principle

The slip table works on the principle of an oil film maintained between the granite surface and the slip plate supported by low/high pressure oil bearings to eliminate overturning moments. An oil film is automatically created through a closed loop system, when the oil pump coupled with the motor is started.

These are ideally suited and designed for testing of medium and heavy loads and voluminous specimens/objects in x, y & z directions. The bearings are designed to restrain pitch, roll and yaw moments. Ambient and combined environment (vibration + thermal) testing are also supported.

Combo Base

Slip tables can be used in a standalone position with the optional seismic base or integrated on a common base with a vibration shaker. The electro-dynamic shaker can be rotated to the vertical position for one axis and then rotated to the horizontal position where it is connected to a horizontal slip plate through a drive bar/coupling for the other two test axis.

Construction

The discharge of hydraulic oil is supplied by a hydraulic pump for supplying oil to the bearings and for the formation of oil fil on the granite block. A pressure gauge is provided for reference.

The slip table platform is made from Mg and has replaceable stainless-steel nut inserts. The Slip Table structure is finished in a gloss and metallic coating of polyurethane paint with various contours.

Head Expanders

Application

To extend the capabilities of the Electro-dynamic shakers we offer a wide range of vertical attachments called “Head Expanders” which are required for mounting and testing large test sampleswhich cannot be directly mounted onto the shaker head in the vertical axis (Z axis).

We have the full capability to design and manufacture head expanders and fixtures to meet your application and requirement needs.

Features

All head expanders are designed using FEA to determine the natural frequency and optimize the performance of the shaker. High quality construction guarantees the reliability of the vibration test system.

The head expander consists of a magnesium cast table surface which is directly bolted onto the shaker head. We offer a wide range of sizes in both round and figural shapes with customized hole patterns and available for any size armature.

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Mechanical Shaker Table

The Mechanical Shaker Table is a low-cost system designed to perform various vibration tests.

Its constructed from a rigid steel structure to sustain the forces exerted on a load up to 100 kg for between 0.5‘g’to 20’g’ and with a Sine waveshape with a variable frequency range from 1 to 60 Hz. The mounting platform lifts vertically up to the desired impact acceleration through a cam arrangement which also gives it the desired acceleration. The motor is driven by an AC drive which has built in protection and controls.

The moving platform is a grid pattern of 100 mm x 100 mm with threaded M10 stainless-steel nut inserts.

The Mechanical Shaker Table is supplied with a vibration meter for measuring vibration parameters like acceleration, velocity and displacement.