testing is not new; in order to study the effects caused by shock
waves to an object many devices have been created. Precise study
requires a testing device that will produce a shock which is predictable,
reliable and repeatable. The 6-Inch Vertical HYGE system is designed
to simulate the effects of a shock in an acceleration rather than
The 6-Inch Vertical HYGE system develops thrust
up to 56,000 lb f (249 KN), it can also produce acceleration values
to several hundred times gravity for milliseconds duration and
it can produce several different waveforms at various levels.
The 6-Inch HYGE Vertical system consists of a 6” (15.2
cm) ID set cylinder attached to a primary load cylinder this is
secured to the mounting base. An optional mounting base can allow
for additional load cylinders.
The thrust column is attached to the thrust piston for the stroke.
This system design provides extremely repeatable and reproducible
acceleration pulses, enabling accurate simulation.
The system has proven its repeatability over time. HYGE systems
over 40 years old routinely demonstrate repeatability of better
than +/- 2%.
The test specimen is either mounted to a light weight carriage
that is attached to a rail system or directly mounted to the thrust
column. Pneumatic brakes are mounted on the carriage. Additional
rail sections and different carriage sizes are available.
The HYGE system offers precise control of pulse shape, excellent
test repeatability and universal acceptance within the automobile
METHODS OF CONTROLLING ACCELERATION
Acceleration of test specimen of the Hyge shock
test is governed by the thrust and the specimen mass. The thrust
is equal to the difference in pressure between the set chamber
and load chamber, times the net piston area exposed. To provide
the control necessary to produce a given acceleration waveform
or shock patter a specific metering pin attached to the underside
of the thrust piston projects through the orifice into the load
chamber. The contour of the pin meters the gas flow through the
orifice, regulating the acceleration and making the utilized thrust
Deceleration can be controlled externally, by means of a rail
and carriage system.
The rail system includes a carriage on which the test specimen
is mounted, this is guided by rails.
Prior to firing the carriage is held in contact with the thrust
Once the unit has been fired and the acceleration phase is
over, the carriage and specimen are brought to rest with brakes
that are mounted to the carriage.
With internal deceleration the set chamber is subdivided into
two chambers with a deceleration orifice.
Part of the set chamber is filled with hydraulic fluid and
there is a deceleration metering pin attached to the thrust
The small test object is mounted to the end of the thrust
Once fired and a distance is traveled the fluid is forced
through the deceleration orifice bringing the thrust column
and test object to rest.
the rails guide the carriage and specimen during deceleration
in order to maintain as low a deceleration level as is desired.
Rails can vary from 8 to 20 feet. Ideally the rail system should
be as long as the overhead clearance permits. Actuator can be
located in pit to increase usable rail length and lower specimen
carriage to floor level.
Carriage: supports specimen mounting onto a
fixture bolted to the carriage. The carriage assembly includes
pneumatic brakes. There are optional emergency brakes for firing
the carriage with decreased primary brake pressure. There is an
included carriage return mechanism.
Foundation: the recommended foundation is six-foot
Actuator: the internal working parts of the
Hyge unit including the thrust piston, thrust column, seal rings
and orifice plate (or plates if deceleration is ordered). There
is also an optional safety interlocking device or lock yokes.
Control System: the touch screen control center
contains a graphical representation of the system. The control
system features an intuitive user interface that provides controls
for every automatic function of the system, from the automatic
filling of the system pressure to the storing of successful test
parameters data. Click
here for more information on the Control System
Distribution Center: the distribution center
contains all of the valves, regulators, power supplies, etc.
Compressed Air: The 6” Hyge system can
be operated from compressed nitrogen bottles. The optional air
compressor decreases nitrogen usage by using compressed air on
the load side of the system, allowing for pressures up to 3,000
psi to be used (extending the range of operation from 40,000 pounds
(178 K Newtons) thrust to 56,000 pounds (249 K Newtons) thrust).
The video below shows a 6” vertical HYGe system with actuator
mounted below floor level, with Sled and 50 foot rail system.
Systems are in use worldwide for a variety of automotive and
aircraft safety testing applications. Some typical applications
Aircraft ejection seat testing
Hand held equipment and small appliances
Hemets and protective head gear
Components and subassemblies
FEATURES AND BENEFITS
Proven Accuracy - capable of simulating actual
crash pulses to within +/-2%.
Reproducibility - pulses can be accurately
reproduced on various systems, enabling sharing of test programs
and results between components suppliers and OEMs.
Versatility - can perform velocity and acceleration
Mechanically Simple - Very few moving parts.
Low Cost Energy - 2200 psi nitrogen
The system is capable of producing a wide variety of shock pulses.
There is a standard half sine wave meting pin supplied with the
system. The pulse may be modified by adjusting the Hyge system
Max. Load Pressure: 3,000 psig (207
Set pressure for Max. Load Pressure:
500 psig (23 bar)
Maximum force with Max. Load Pressure: 56,000
lbf. (249 K newtons)
See Layout Below
Load Cylinder: 6 inches (152 mm) diameter
bore, max length of 72” (183 cm) varies depending
on test needed
Set Cylinder: 6 inches (152 mm) diameter
bore, length varies depending on test needed
Maximum stroke length: up to 36 inches
(91 cm) length varies depending on test needed
Maximum Acceleration: 64G (627.6 m/s2)
Maximum payload: 1000 lb. (455 kg)
115/230 VAC, 50/60 Hz for control system
Compressed dry nitrogen in regulated bottles that can
hold 2200 psi (137 Bar) (optional air compressor for load
pressure allows for operation up to 3,000 psi (207 bar)