This document introduces the basics of shaker table control and provide a reference design that uses National Instruments (NI) CompactRIO and LabVIEW to control vibration tables generating sweep sine and random vibration.

A vibration test is important in product design and quality control because the vibration in transportation or operational environment might damage the product.  For example, the parts of a truck might become loosen on a bumpy road.  A satellite might be damaged by the shock that occurs when the rocket launches. Vibration test is necessary to ensure that a product survives the transportation or operational environment.  Vibration test is almost a must in the military and aerospace industry and also common in the automotive industry and consumer electronics.

Performing vibration test in real-world vibration environment is expensive, unsafe, or even unrealistic. Usually engineers use a vibration test system to simulate the vibration environment in a lab and then test products in the lab. A vibration test system is composed of a vibration table (shaker), an amplifier, a controller, and accessories as shown in Figure 1.  The controller acquires the vibration signal of the vibration table through the accelerometer and then generates a proper driving signal for the amplifier according to the vibration signal of the vibration table.

Typically a vibration test system can generate sweep sine, random, and shock vibration. A vibration test system also can replicate a recorded vibration. You also can combine one type of vibration with another. For example, combine sweep sine vibration with random vibration or combine two random vibration types.  Shaker control is the technique to tune the driving signal voltage for the vibration table so that the vibration table generates expected vibration.  Control algorithms inside the controller use the actual response acceleration of the vibration table as feedback to adjust the excitation signal to be applied to the vibration table until the actual response acceleration is as expected. NI CompactRIO is an ideal platform for shaker control. NI CompactRIO is a small rugged industrial control and acquisition system powered by reconfigurable I/O (RIO) FPGA technology for ultrahigh performance and customization. NI LabVIEW graphical programming tools hide the complexity of rapid embedded system development. With NI CompactRIO and LabVIEW, you can develop low-cost shaker controllers rapidly.

Refer to the doc file in the attached zipped file for more information about shaker table control and the example codes.

Contacts: If you have questions, please contact nanxiong.zhang@ni.com or dsp.nish@ni.com.