"Failure of physical testing by using prototypes used to incur a large time and cost penalty while the structure was redesigned, and another prototype built. The advantage of using Altair HyperWorks was that it saved us huge time, cost, and effort and yet delivered the desired results in terms of a robust ROPS design in record time."
Reymond Van Rensburg
Design Manager, IDES
One of these Australian Army G-Wagon variants was intended to be used as the surveillance and reconnaissance (S&R) vehicle. The role of the S&R variant was to provide high-mobility transport to the Regional Force Surveillance Units for conducting wide-area surveillance tasks. The vehicle, when on patrol, is operated by three personnel—a driver, a co-driver, and a rear observer.
In the S&R module for this project, the rear observer was to be seated in the vehicle module. The IDES team was required to design the module with adequate protection for the rear observer in the event of a vehicle rollover. The team decided to build a vehicle rollover protection structure (ROPS)—a system that is aimed at protecting occupants in the event of a vehicle rollover. To make the module robust so that it provides maximum protection, the team wanted to build the ROPS in the form of a tubular roll cage structure.
This ROPS structure could be developed by using an iterative physical testing process such as a pendulum, which simulates the energy absorbed in a rollover event. But the team knew that physical testing would be inherently time, effort, and cost intensive because it meant building physical prototypes and destructively testing them to gain useful results. The challenge for the team was that the LAND 121 Phase 3A project did not allow for the time required to perform multiple physical tests to ensure best performance of the S&R module’s ROPS. For this time-intensive critical project, the team wanted a solution that would enable them to deliver a high-quality, tough, and reliable ROPS within minimum time duration.
Using Altair HyperWorks to Build, Test, and Accomplish an Optimum Product Design
IDES is known for their expertise in the vehicle development industry; they follow a very structured Product Development Process for all their projects. As a key part of the process, the company utilizes CAD and CAE tools during the concept and systems development stages. The sole objective of this approach is to optimize product structures and minimize physical prototyping and testing required for product verification and validation. To this end, IDES has been using Altair HyperWorks for many years; in fact, the tool has been the only CAE package that they have been using for a number of years. The company relies on the software suite as it offers all functions required for quality product development. In case of the LAND 121 Phase 3A project too, the IDES team decided to use Altair HyperWorks to develop the ROPS and simulate the testing process.
The team began by creating a finite element model of the pendulum test rig, base vehicle chassis, and S&R module using Altair HyperMesh™. Physical testing was simulated using the physical testing process by using Altair Radioss™ and processed the results in Altair HyperView™.
Developing a High-priority Product within a Stringent Deadline
Altair HyperWorks was instrumental in enabling IDES to quickly, efficiently, and accurately develop an optimum design for the ROPS. The IDES team saved invaluable time by using HyperWorks for the LAND 121 Phase 3A project. By performing this simulation, IDES saved valuable time while revising and significantly improving the structures’ strength and safety.
Finally, within the allocated time and budget, the team developed a virtual ROPS design that had adequate strength to protect the vehicle occupant. They verified the final design through a physical test, which demonstrated a good correlation to the simulation results.
The G-Wagon S&R Module is now in service with the Australian Army. The IDES team is very enthusiastic about leveraging the capabilities of the Altair HyperWorks suite to enable rapid, reliable, accurate, and safe development of mission and safety-critical systems.