How we redefine tipping trailer safety

At STAS, safety isn't just a feature—it's a fundamental part of our engineering philosophy. We know that tipping a fully loaded trailer involves complex mechanics, and the stakes are high for drivers, operators, and fleet managers alike.
Our commitment to operational safety focuses on two key areas:
1. Maximizing Safety Margins: Through rigorous engineering, high-quality materials, and optimized manufacturing, we ensure our trailers are safe under all conditions.
2. Educating Operators: By sharing insights and best practices, we help ensure trailers are used safely and effectively.
Safety is not just a checkbox; it's a continuous challenge and a shared mission between STAS and our end users.
Engineering Safety into Every Trailer
To ensure our trailers meet the highest safety standards, we combine Finite Element simulations with real-life physical testing. This dual approach allows us to refine our designs and continuously improve the safety of our tippers.
This article is the third article in our series about tipping trailer safety and dives into our design process, showcasing how we ensure stability and operational safety across our tipper range.
• Click here to read the first blogpost: The physics of tipping trailers
• Click here to read the second blogpost: Best practices for safe tipping
Maximizing safety margins
As we discussed in earlier blog posts, a trailer tips over when its center of gravity shifts beyond its base of support. When the center of gravity shifts, certain parts of the trailer can deform, potentially compromising safety. This is where our engineering team steps in—designing trailers that minimize this deformation without adding unnecessary weight.

Critical Trailer Components
Some parts, like the tires and suspension bushings, are designed to deform to ensure a smooth and safe driving experience. While these components can't be stiffened without sacrificing ride quality, we only use premium parts to ensure optimal performance. Regular maintenance of these components further enhances safety.
To improve overall stability, we focus on stiffening the chassis, tipping hinges, and body. However, just adding more metal isn't a solution— we have to balance strength and empty weight.
Balancing strength and empty weight: The STAS design cycle
A tipping trailer must be as strong as possible while at the same time being as light as possible. Achieving this balance starts with simulations, but simulations are only as good as the data behind them. To ensure accuracy, we rely on real-life measurements from physical tests.
We began this process with our S700 steel tipper chassis. Of course, the same process will also be applied to the alumium chassis later on.
Here's how the design process unfolds:

Simulation model
The first step involves converting 3D production drawings into a model suitable for simulation software. This includes inputting material properties—from the Young’s modulus of the sheet supports supports inside the body to the stiffness of tires.

Since not all parts are designed in-house, gathering data on components like the ram's lateral strength and stiffness of the suspension bushings was a research project in itself. Fortunately, our premium suppliers provided the necessary information.
The load case
To make simulations realistic, we program scenarios where the trailer is fully loaded and tipped without the load sliding out. The model, attached to a simplified simulation model of the truck, also incorporates gravity applied at the center of gravity.

Trailer prototype
With the constraints set, we iteratively adjusted the 3D model—over 200 times—until achieving the best weight-to-stability ratio. This led to the creation of a prototype that was produced in-house on the factory line to guarantee repeatability in the future.

Physical testing
A simulation model can only predict up to a certain level of accuracy. To validate our models we conducted physical tests at IDIADA in Spain, renowned for their testing facilities and in-house expertise when it comes to testing automotive parts and systems.

Data capturing
During the tests, we collected precise measurements to compare against our simulations:
• Inclinometers measured torsion at key points.
• Six cable transducers tracked the load on each individual wheel.
• A full 3D scan captured deformations at various tilt angles.
All data was processed using in-house software, resulting in a comprehensive dataset for analysis.
Data analysis
Real-life data is often messy, so we refined the sensor outputs to create a clean dataset. This allowed us to benchmark simulations against reality, making our stability claims real-life validated—a unique advantage in the market.
Our analysis also revealed how factors like uneven load distribution or incorrect tire pressures impact stability. Click here to learn best practices for drivers and operators.
The results: What it means for you
Our testing proved that the new STAS steel chassis exceeds expectations for operational safety. We confidently state that this chassis sets a new standard in the tipper market.
- The trailer withstood tilt angles of 9° multiple times in a row without wheels lifting or any lasting deformation.
- After rigorous testing, the trailer was checked and received green light to return to the road in perfect condition.
Beyond validating our design, we’ve gained invaluable insights into maximizing safety for drivers and operators. Learn more about how to optimize your trailer’s safety.

The Road Ahead: Zero Harm in Bulk Transport
With our real-life validated digital models, we’re set to optimize every tipper configuration in our wide range of tippers—from aluminium to steel chassis. This means concrete stability metrics for each model.
We’ll also expand our best-practices checklist, providing a practical manual for all operators. Our journey towards zero harm in bulk transport continues, driven by curiosity and commitment.