Going over pot-holes could easily be rated as the worst part of a commute…well that, and traffic perhaps. It is no surprise to anyone that our public infrastructures are aging and in need of revamping. Recent studies have shown that a majority of U.S. highways are considered to be in poor condition. As governmental organizations work on new infrastructure plans, automotive manufacturers are also trying to improve our daily commute and ensure our vehicles remain safe on the roads. One of the best ways to ensure structural and functional integrity of a vehicle and its components is through vibration durability testing.
In order to simulate rough road conditions, vehicle manufacturers collect data on an actual vehicle driving on their proving grounds. The proving ground include courses designed to mimic public road scenarios such as speed bumps, pot-holes, train tracks, and any other relevant events that could be experienced in an everyday commute. The data collected often comprise of accelerations, as well as stress and strain measurement on different vehicle components.
This data is then processed using a pseudo damage algorithm that focuses on high amplitude acceleration peaks exerted on components through the road scenarios endured. A test profile is then developed to simulate these high stress events for the lifetime of the vehicle on Multi Axis Simulation Table (MAST). The MAST, being very common in hydraulic test laboratories, is made up of six single loop servo-hydraulic actuators capable of shaking a large rectangular table top up to six degrees of freedom. MGA has over a decade of experience designing and operating these types of vibration machines and offers such services in nearly all its engineering operations.
Similar to a MAST. system, custom hydraulic durability tests involve putting two MAST tables in proximity is one way to create a custom vibration rig. Intuitively, we call this configuration a dual MAST. The purpose is to be able to capture a larger footprint test subject with the same six degree of freedom movement. This equipment is commonly used for full vehicle exhaust systems from engine to tail pipe. Having two independent mounting surfaces for the exhaust piping allows the rig to mimic the front and rear portions of the vehicle separately but in harmony. Add a hot gas furnace to the mix and you can closely resemble a functioning exhaust system while it experiences vibrations from driving down the road. At MGA’s hydraulic lab, we have a dedicated dual MAST system equipped with clamping mechanisms on each actuator in order to prevent the table tops from losing height in the event of the loss of hydraulic pressure or a power outage. This ensures integrity of the sample no matter the circumstances.
Another example of a custom hydraulic piece of equipment involves removing the table top of the MAST and attaching your hydraulic actuators directly to the test specimen. Commonly know as the industry term “seven-poster”, due to the system being made up of seven hydraulic actuators, this typically would be all or part of a vehicle frame but would also be effective when testing a cab, truck bed, even an axle. The advantage of attaching directly to a section of a vehicle is the added maneuverability while capturing a larger portion of that vehicle. With an extensive experience in testing full frames up to semi-trucks weighing up to 8,000 lbs., this yet another unique capability offered to our customers.
Other types of Custom Hydraulic durability tests supported
MGA has decades of experience providing vibration solutions and the ability to design and manufacture our own equipment. We are always ready to accommodate the testing demands that arise as the automotive industry continues to innovate and advance.