Prototype design Hungary: Amber One Project
Goal of the Amber One Project was to design a prototype vehicle with carbon composite passenger cell and wheel-hub drive and to build the adjacent platform.
Low mass, high power, right vehicle dynamics as well as adherence to safety regulations, to the extent permitted by circumstances, played an important role in defining the concept. The team was given a relative great freedom in development (ranging from specification to the testing of the car) providing an outstanding opportunity in Hungarian standards.
Efficiency is key
Little time (12 months) was available for the project: a complete, fully parametric, multi-levelled complex skeleton system had to be built up to define the entire vehicle. With the use of the skeleton based system, following a Top-Down design philosophy, there is no need to manually modify the individual components in case of any necessary alteration, as this procedure can be automated. The team had several years’ routine in this field. It was developed in the course of the successful projects of recent years. With the design that they have developed, the requirements for the vehicle can be met at the levels of system, assembly and components. The new construction concept integrates the components in a well functioning unit. This results in significant shortening of development time, moreover, repairs can be managed more easily.
Freestyle, the new surface modelling module of Creo 3.0., made it possible during design that the Class-A surfaces could be created quickly and easily in the same CAD environment in which the rest of the modelling is done. Creating continuous surfaces provided a great advantage as importing a master surface made with a different software was not necessary. Besides, both the exterior and the interior of the vehicle could have been altered with ease.
The monocoque frame incorporates the ergonomic and safe passenger cell, ensures appropriate rigidity and contact surfaces for the rest of the elements. Most efficient modelling of the frame, made of carbon-fibre reinforced composite, can be done with surface modelling. The geometry of the frame was designed with this technique. Throughout the work, the versatile surface modelling functions of Creo 3.0. have proven to be very useful. The composite frame was cemented together from several shell-elements. The design of the contact surfaces required that these be parametrically modelled in a single skeleton part. Following this, the idividual shell-element geometries could be published in separate parts in lower levels, where the tools were designed for each given element.
Installing Range Extender
The electric power provided by the generator of the range extender charges the battery that drives the motors. A complex system is responsible for the control of this procedure. This consists of an internal combustion engine, an inverter as well as the systems of cooling, electric control, fuelling, suction and exhaust. Because of the complexity, it was indispensable that the contact points of these units to one another and the rest of the vehicle would be carefully designed. This was made possible by the appropriately structured design of the model. A single main skeleton contains the necessary contact points as well as the sketched geometry of the individual components. Detailed elaboration of the full assambly was done after the publishing of the main skeleton. The system made it possible that, after modifying certain dimensions, the geometry of the frame, the channels of cooling, the wiring of the electric system as well as inlets and outlets on the body could be automatically modified accordingly.
Systems of drive, control and other supplements
Being an electric vehicle, a great number of electric units needed to be placed in the car. These needed to be fixed appropirately and the electric connection had to be ensured (cable whips). Moreover, water cooling needed to be ensured for modules of greater power.
Electric units purchased and developed in-house were installed in the vehicle. In the case of units purchased, the STEP model and instructions were provided by the manufacturer. These determined the fixing and connection surfaces of the given components. In case of self-developed devices, these were defined after conciliation with the electric engineers.
The design of the cable whips, brake- and cooling systems was done in a similar way. After defining the final position of the electric components, the location of their contactors was determined. Routing of the high- and low-voltage cables, cooling- and brake tubes was done subsequently and finally the entire system fit together.