The required product was an electrically operated access step and control unit for AVS Steps and their customer BMC Trucks (UK). It’s function to improve the accessibility to the rear cab of the BMC Crew Cab Chassis so that they could expand their sales into the roadside recovery vehicle market.
The project...
The design was easy to define as the dimensional properties of the finished product were dictated by those of the specific vehicle and the objective of the project – improving pedestrian access to the cab of the vehicle.
Another important aim was to use as many materials, methods and components from other AVS Steps' products. This was to keep tool cost to a minimum, allow the new product to be assembled with existing production equipment and ensure it would be similar in appearance to the company’s other products.
The solution...
Following detailed measurement and analysis of the vehicle it was apparent that the distance between the ground and floor of the cab ideally needed four steps for comfort and to ensure that someone less able could use them.
The proven and accepted method for a multi-tier folding step is a series of linked mechanical parallelograms, however only three tiered versions had yet proven successful. Therefore it was decided that the first three tiers from the ground up would be on a series of linked mechanical parallelograms mounted to a rolling chassis which had the fourth tier mounted to it and deployed from a second chassis mounted to the vehicle.
The final product successfully used many materials and methods from other AVS Steps' products, the new bespoke parts that were required were either machined parts or sheet metal fabrications that required no specialist tooling.
