REL, Inc. Expanding Split Hopkinson Pressure Bar (Kolsky Bar) System Capabilities to Perform Impact Testing

REL, Inc has converted its Split Hopkinson Pressure Bar(Kolsky Bar) so it is capable of performing impact testing with wider range and more flexible energy, easier single impact events with a lower cost system. It has many advantages over a typical drop test system.

Calumet, MI, March 07, 2018 --( REL’s latest system demonstrates that converting our Split Hopkinson Pressure Bar (Kolsky Bar) to an Impact Tester is a seamless transition. In fact, many of the pieces required for impact or drop testing are already in place.

The below videos are of the same event from both sides. One with an iPhone in slow motion mode 250 frames/second and the other with a Shimadzu HPV-X2 high speed camera at 10000 frames/second. A striker of a set mass is launched at the desired speed to obtain a set impact energy. A high-speed piezoelectric load cell is mounted on the stop stand to measure the transmitted load and Point Tracking with the high speed camera in conjunction with DIC in REL’s SURE Pulse to monitor the deflection during the event are used to plot the load-displacement curve of the impact event.


The required modules to perform an impact test or drop test are as follows:

1. Launching system – Same as SHPB
2. Striker mass accelerated at a set rate – Several lengths included with SHPB and more exact masses of various materials can be easily manufactured.
3. Speed Sensor to know exact energy upon impact – Same as SHPB
4. Load cell on Stop Stand or transmission bar to determine transmitted load. – Stop from SHPB now includes a high speed piezoelectric load cell
5. Camera or measuring system to track the impact event – up to 10000 frames per second is sufficient.

Tailored speed impacts from 10 to 150 feet/second are easily obtained with various weight striker bars. An available striker stop system insures single hit events.

The advantages of this system over typical drop test systems are:

1. Wider range and flexibility of energy that can be put into an impact event.
2. Easier Single impact events as the mass is moving horizontally.
3. Lower Cost system – more so if you already have SURE-Test System or SHPB System.
4. Safe, Enclosed impact chambers
5. Impact testing modules reside on the same SURE-Flat platform, and often can be set up simultaneously with a SHPB test setup efficiently uses lab space.

REL, Inc. is a manufacturer of Split Hopkinson Pressure Bars. Our 3rd generation SURE-TEST Systems are designed to be modular in nature. This flexibility allows the system to be configured in different sizes, lengths and to integrate different testing modules. These variations give the system the ability to conduct a wide variety of test configurations in addition to classic SHPB testing. Contact us today for your dedicated impact testing or drop testing needs.

Adam Loukus, Ph.D.
Adam Loukus, Ph.D.