Manufacturer we represent

Emerson Apparatus in the Southeast

Shock machines, mechanical shakers and package test systems built in Maine, carrying forward VST and M/RAD engineering.

Headquarters: Gorham, ME
Founded: 1908
Coverage: All Vaughn Associates territories

About Emerson Apparatus

Emerson Apparatus is a privately held manufacturer in Gorham, Maine, that designs and builds mechanical test equipment used to prove products survive shock, vibration, sustained acceleration and distribution handling. The company traces its roots to 1908 and is unrelated to Emerson Electric Co.

In 2019 Emerson Apparatus acquired Vibration & Shock Technologies (VST), the Woburn, Massachusetts company formed in 2011 by former M/RAD Corporation staff. VST’s shock machines, mechanical shakers and package test systems are now built in Gorham, and VST customers continue to be supported there.

What Emerson Apparatus makes

Shock testing is the core. PSM Series pneumatic shock machines carry 100–2,500 lb payloads and reach up to 30,000 g, while FSM Series free-fall machines range from 5 to 5,000 lb with tables up to 60 × 60 in. ShockTool software handles machine control and pulse analysis.

For vibration, ES, VS and VH mechanical reaction-mass shakers deliver high force at low frequencies with payloads up to 15,000 lb. Package and distribution testing is covered by TS Series transportation simulators, DT Series drop testers, incline impact testers and test centrifuges.

Emerson Apparatus also supports labs running other brands’ equipment. It designs magnesium head expanders, slip plates and custom fixtures for electrodynamic shakers, using finite element analysis to push resonances out of the test band. It also rebuilds legacy AVEX shock machines and retrofits PC-based controls to M/RAD and VST machines.

Why engineers specify Emerson Apparatus

Standards coverage. Equipment supports testing to MIL-STD-883, MIL-STD-810, MIL-STD-331, RTCA/DO-160G, FED-STD-101, ASTM D999 and ISTA procedures, including ISTA-6A.
High-g capability for semiconductor and microelectronics shock qualification.
Life extension for existing labs. Control retrofits, programmer pads and rebuilds keep proven machines in service.
Traceable controls. Control systems can ship with ANSI Z540-1 calibration certificates.
Engineering heritage. Designs carry forward decades of M/RAD and VST shock and vibration experience.

Local support from Vaughn Associates

Huntsville’s missile, space and avionics programs, Southeast automotive suppliers and regional package-testing labs all depend on qualification testing. Vaughn Associates helps test engineers match payload, peak g, pulse shape, frequency range and test standard to the right machine.

We coordinate quotes and technical reviews with Emerson Apparatus, help plan upgrades for legacy equipment, and stay involved through delivery. Vaughn covers Emerson Apparatus in all of its territories.

Request application help, explore shock and vibration test equipment, or find your local rep.

Pneumatic shock machines reaching up to 30,000 g

Equipment built and supported in Gorham, Maine

VST and M/RAD engineering heritage

Control retrofits and rebuilds for legacy shock machines

FEA-designed magnesium fixtures and shaker peripherals

Product lines

What Emerson Apparatus makes — product categories we can help you specify.

Pneumatic shock machines

Closed-loop shock machines for 100–2,500 lb payloads that produce half-sine, square-wave, trapezoidal and terminal-peak sawtooth pulses, reaching up to 30,000 g for microelectronics testing.

PSM100
PSM500
PSM1000
PSM2500

Free-fall shock machines

Drop-table shock machines for payloads from 5 to 5,000 lb with tables from 4 × 4 in to 60 × 60 in, with shock amplifier and bungee-assisted options.

FSM20-0505
FSM50-0707
FSM200
FSM1000
FSM5000

Mechanical reaction-mass shakers

Elliptical, vertical and combined vertical/horizontal shakers delivering high force at roughly 10–60 Hz on tables up to 120 × 120 in with payloads to 15,000 lb.

Transportation simulators

Package vibration systems with circular synchronous, vertical linear, non-synchronous and out-of-phase motion, from parcel-size units to pallet-load machines.

TS100
TS300
TS500
TS2000
TS4000
TS6000
TS8000

Drop testers

Manual and pneumatic touchscreen drop testers for package handling tests with drop heights from 4 to 84 in.

DT20
DT50
DT100
DT250
DT500

Incline impact testers and test centrifuges

Incline impact testers for 1,000–10,000 lb loads with laser velocity measurement, and programmable test centrifuges for sustained acceleration testing.

Electrodynamic shaker peripherals and fixtures

Magnesium head expanders, slip plates, bases and cube, L and T fixtures designed with finite element analysis to keep resonances out of the test band.

Shock machine refurbishment and control upgrades

Rebuilds of legacy AVEX shock machines, air-to-hydraulic braking conversions, PC control retrofits for M/RAD and VST machines, and programmer pads for all makes.

AVEX SM-105 rebuild
AVEX SM-110 rebuild
AVEX SM-220 rebuild

Control software and instrumentation

Shock machine control and pulse analysis software, vibration monitoring and sweep control, and touchscreen interfaces for package test equipment.

ShockTool
Vibration Tool (VT Software)
DAS4U

Applications

MIL-STD-883 high-g shock for microelectronics
MIL-STD-810 shock and vibration qualification
Sustained acceleration testing to RTCA/DO-160G
ISTA and ASTM D999 package testing
Transportation simulation for parcels and pallets
Drop and incline impact testing
Munition and fuze package testing
Retrofitting legacy M/RAD, VST and AVEX shock machines
Head expanders and slip plates for electrodynamic shakers

FAQ

Common questions about Emerson Apparatus

What happened to Vibration & Shock Technologies (VST)?

Vibration & Shock Technologies, LLC was founded in Woburn, Massachusetts, in 2011 by former M/RAD Corporation staff. Emerson Apparatus acquired VST in 2019, and VST's shock machines, mechanical shakers and package test systems are now built and supported by Emerson Apparatus in Gorham, Maine. The former vstcorp.com website redirects to emersonapparatus.com, and existing VST customers continue to be supported.

Is Emerson Apparatus part of Emerson Electric?

No. Emerson Apparatus is a privately held test equipment manufacturer in Gorham, Maine, with roots dating to 1908, and it is unrelated to Emerson Electric Co. The company builds shock machines, mechanical shakers, transportation simulators, drop testers and related test equipment, including the product lines it acquired from Vibration & Shock Technologies (VST) in 2019.

How much shock can an Emerson Apparatus pneumatic shock machine produce?

The PSM Series pneumatic shock machines handle payloads from 100 to 2,500 lb and can reach up to 30,000 g for MIL-STD-883 microelectronics testing. They generate half-sine, square-wave, trapezoidal and terminal-peak sawtooth pulses under closed-loop control and offer horizontal test capability. A shock amplifier option is available for very short, very high-g pulses. Free-fall machines cover payloads up to 5,000 lb.

When should I choose a mechanical shaker instead of an electrodynamic shaker?

Mechanical reaction-mass shakers suit low-frequency, high-force testing, roughly 5–60 Hz, with heavy payloads at a lower cost than an equivalent electrodynamic system. Emerson Apparatus mechanical shakers carry payloads up to 15,000 lb but are generally limited to about 10 g. Electrodynamic shakers are the better choice for broadband random vibration and higher-frequency test profiles.

Can old M/RAD, VST or AVEX shock machines be upgraded?

Yes. Emerson Apparatus retrofits PC-based controls to M/RAD and VST shock machines, rebuilds AVEX SM-105, SM-110 and SM-220 machines, converts braking systems from air to hydraulic, and supplies programmer pads for all makes. Control systems can be delivered with ANSI Z540-1 calibration certificates. Upgrading a proven machine is often a practical way for a test lab to extend its capability.

Who represents Emerson Apparatus in the Southeast?

Vaughn Associates, Inc., an independent manufacturer's representative headquartered in Huntsville, Alabama, represents Emerson Apparatus in all of its territories. Vaughn's engineers help test labs match payload, peak g, pulse shape, frequency range and test standard to the right machine, coordinate quotes and technical reviews with the factory, and support upgrade planning for existing shock equipment.

Local support

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