Dolly Prototype Will Showcase Industry Innovation

dolly prototype will showcase industry innovation

A trial to measure the performance of an industry converter dolly prototype will showcase industry innovation, demonstrating superior capabilities when compared to other units, writes Bob Woodward, Australian Trucking Association Chief Engineer.

Led by the Australian Trucking Association’s Industry Technical Council, our prototype was developed after concerns were raised about dynamic issues with hinged drawbar converter dollies, particularly brake reactivity and tyre wear. The new unit removed the pivot point of a hinged drawbar, making a dramatic difference in the brake system control.

The rigid drawbar converter dolly was developed in partnership with industry suppliers and manufacturers MaxiTRANS, Bridgestone, Hendrickson, JOST, Wabco and Alcoa, and has since undergone informal trials with operators across the country.

While we had received informal feedback from these trialing operators, we wanted to get the real data that could highlight just what effect the dolly would have.

After a few delays due to Covid-19 restrictions, Industry Technical Council members were finally able to come together for a formal trial. With the support of the dolly partners and Toll Group, we came together in Corowa, NSW, to evaluate the converter dolly’s performance and acquire measurable data using inertial measurement units, strain gauges and GPS.

dolly prototype will showcase industry innovation

The trial looked to complete back-to-back testing of the rigid drawbar dolly and a standard hinged drawbar dolly when used in an A-double combination, comparing the lateral force accelerations seen in each of the vehicle units to determine which is better.

We placed the inertial measurement units above the axle group in the lead trailer, the converter dolly, and the trailing trailer to measure roll, pitch and yaw, and lateral, longitudinal, and vertical acceleration.

Strain gauges were fitted on the converter dolly fifth wheel pedestals and towing eyes to measure correlation of forces and comparative stresses, while the GPS recorded positioning and speed.

The initial observations left our members really surprised, especially at how severely the hinge drawbar pitched and danced around the road in comparison to the rigid drawbar.

This dolly project was about building a safer, better performing dolly than those already on the market.

dolly prototype will showcase industry innovation

Over three years, this project has evolved from concept to reality. Since its development and success in trials, MaxiTRANS have already manufactured a number of these dollies for Australian businesses who understand the value and benefits the design delivers.

Those who have trialed it say it performs better than other dollies and have been immediately convinced it is a superior piece of equipment.

One such business, Kel Baxter Transport who were sold on the idea from the beginning and have since had a dolly manufactured with another on the way.

The difference in the vehicle’s stability when using the converter dolly during the trial was incredible. Visually, the trial demonstrated how much more settled the combination with the rigid drawbar converter dolly was on the road, tracking and in corners.

It’s amazing to see what can be achieved in our industry when the talent and expertise can be brought together to deliver real outcomes.

The data gathered from the trial is now going through an analysis and evaluation process, and I look forward to examining the findings of the difference in performances between the two units.

Once completed, the data will be shared with industry and discussed in-depth, during the ATA’s TMC Online event from 27-28 July. This is an opportunity to hear exactly how the innovative dolly performed and hear firsthand from those who have trialed the unit and the impact it has had on their operations.

To find out more about the Industry Technical Council or the TMC Online event, head to 

dolly prototype will showcase industry innovation