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Servo-Hydraulic Six DoF Vibe Table Buyers Guide
Back to Buyers Guide
Please note that this information is intended as a guide only. Individual needs vary, for help with a controller to meet your needs, contact us. Presented in alphabetical order of manufacturer, with no bias.
IST
MAST-97xx
Strong-Wall MAST |
Vendor Link |
| Pros |
Cons |
- Large range of sizes
- Lower moving mass
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- Small installed base
- Expensive
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| Comments |
| I think it is a shame that IST products are not more widely used in the automotive-structural-fatigue-vibration-component testing sector. My opinion is that they have suffered from insufficient marketing, and their prices are set too high. IST systems are generally of good quality, and the company has been around for many years, and so they have a lot of experience. "3-2-1" MAST tables generally fall into two main categories; those that use bell-cranks, and those that use a strong-wall. IST has used both designs, but this review focuses on their strong-wall design. Their tables use the PK swivel reviewed in the Swivels section, and the controller is reviewed here. |
Moog
Hexatest 33 and 66
Stewart Platform MAST |
Vendor Link |
| Pros |
Cons |
- High Frequency Capability
- Worldwide support
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- Higher displacements
- Fewer bearings
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- No Three Variable Control
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| Comments |
| Moog-FCS have a lot of experience with Hexapods. They were developed for flight simulators, and so they have more experience than anyone in this area. Hexapods use the Stewart Platform concept. Control of this type of system is usually pretty challenging, however it is made easier these days with Degree of Freedom control (which they have). While they have delivered some of these using third party actuators, they now have developed their own line, which leverages their experience in the airospace industry. I believe they build the best actuators in the business. |
MTS
Model 323
Bell-Crank MAST |
Vendor Link |
| Pros |
Cons |
- The Orininal MAST
- Worldwide support
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- Small footprint
- Three-Variable-Modal-Conrtol
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| Comments |
| MTS is the market leader, and they have a lot of experience. They have now updated their standard controller platform to include Three Variable Control. This allows you to control displacement at low frequencies, acceleration at high frequencies, and velocity in between. All this can be done in Cartesian coordinates, based around an arbitrary point (around the specimen center of gravity for example). I believe this is the only controller that can do that out of the box. |
MTS
Model 353
Stewart Platform MAST |
Vendor Link |
| Pros |
Cons |
- High Frequency Capability
- Worldwide support
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- Higher displacements
- Three-Variable-Modal-Conrtol
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- Expensive
- Fixed Actuators (more bearings)
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| Comments |
| This was MTS' attempt to compete with Team's CUBE. It is a high frequency system, and with +/–37mm of horizontal displacement, exceeds the envelope of the CUBE, but the velocities and accelerations are lower. It uses the Stewart Platform concept. Control of this type of system is usually pretty challenging, however it is made easier these days with Degree of Freedom control. I do not believe MTS has sold many of these systems. |
Shore Western
Strong-Wall MAST |
Vendor Link |
| Pros |
Cons |
- Large range of sizes
- Lower moving mass
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- Fewer bearings
- Economical
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- Small installed base
- Hybrid Controller
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| Comments |
| Shore Western has been working on moving from a component supplier to a systems supplier, and they have been focusing a lot of their efforts at the MAST market. Those of you who have attended the Testing EXPO in Detroit will have seen their mini MAST. It is rather ironic, since SW has been building large seismic tables for a number of years. SW is interested in growing this business, and so they would be more willing than most to build a table that specifically meets your size and budget needs; but they also have the least experience. Their hybrid controller cannot do a complete Degree-of-Freedom control, becuase the PID loop has to remain on an actuator basis, but they do have a transform for the function generator and set-points. |
Team
CUBE |
Vendor Link |
| Pros |
Cons |
- Large Installed base
- High frequency capability
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- Self contained small footprint
- Works well in chambers
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- Limited displacement
- No standard controller
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- Susceptible to oil contamination
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| Comments |
| If I was to award a vendor a hardware design award, this would be the one. The CUBE is very innovative. I like the fact that the six actuators are orthogonally mounted, and it is obvious what each of them do, making a six degree of freedom simulation very intuitive. I like the clean packaging. The Cube works very well in an environmental chamber, with a few modifications (make sure you order it that way). The disadvantage of the CUBE is the fact that everything is buried inside, and the system is very susceptible to dirty oil. All is OK until you take it apart, then you have to be VERY careful to avoid contamination. If you buy one, I recommend going with Moog valves. You loose some high frequency response, but the thing will still go to 250Hz, which is plenty for most automotive work. Also, Team does not have their own controller, so they use whatever is available on the open market, depending on your needs. I think this ultimately hurts them. |
Team
Bell-Crank MAST |
Vendor Link |
| Pros |
Cons |
- Hydraball swivels
- Works well in chambers
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| Comments |
| Team has also built a few MAST tables. Since vibration is their specialty, I would trust them to build a stiff light table, and their use of the Hydraball swivel is a definite plus. Their MAST is very similar to the MTS design, but with better swivels. These swivels work much better in environmental chambers than any of the others. A big negative, however is the fact that they do not have their own controlller. |
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