Improved Mobility Through Greater Modularity

Together with international license partners, Carrosserie HESS AG produces more than 2,400 buses each year, used worldwide. The leading Swiss manufacturer of buses, trolleybuses, and commercial vehicles employs around 1,100 people and generates annual revenues of over CHF 380 million. HESS stands for innovative, environmentally friendly mobility solutions, particularly in public transport. Electrical engineering plays a central role in the planning, development, and implementation of new solutions – as do the tools used in the process.

“Every tool landscape eventually reaches its limits. We reached that point in 2023 and began renewal with a comprehensive evaluation. One of our main goals was to leverage the advantages of a modern engineering solution while still being able to map HESS-specific requirements.”

Pascal Ellenberger, Head of Mechatronics, Carrosserie HESS AG

A HESS bus typically consists of 4,000 to 8,000 parts and components, connected by up to 12 km of cabling. Until recently, the responsible team used a traditional, graphics-oriented ECAD system that allowed flexible implementation of the specific requirements of electrical engineering in bus manufacturing. However, this came with several drawbacks:

• Manual effort: Almost every electrical diagram had to be recreated for each project, limiting efficiency gains. 
• Error rate: The lack of synchronized data and automated processes led to more errors, more corrections, and increased time expenditure. 
• Lack of modularity: Without a central database, representing modular structures – i.e., reusable engineering components – was nearly impossible. 

To meet increasingly demanding customer requirements – including the trend toward modular E/E architectures and centralized control systems in vehicle manufacturing – HESS launched a multi-stage evaluation in 2023 to introduce a modern CAE system. In the final round, which included visits to reference customers of the two remaining vendors, AUCOTEC Engineering Base prevailed.

The evaluation was followed by a multi-month test phase coordinated by ROTRING DATA, AUCOTEC’s Swiss representative. The goal of this proof of concept (PoC) was to optimally prepare the team for productive use.

“The mobility industry – especially bus manufacturers – places specific demands on engineering tools. The collaboration between our project team, AUCOTEC, and ROTRING DATA quickly became well-coordinated. This allowed us to map our operational specifics in Engineering Base and gradually transition to productive use.”

Pascal Ellenberger, Head of Mechatronics, Carrosserie HESS AG

During the PoC phase, the HESS team used a temporary Engineering Base Cable license provided by ROTRING DATA. This version is specifically suited for engineering special vehicles (planning, wiring, etc.). At the same time, verifying additional HESS-specific requirements was crucial.

AUCOTEC and ROTRING DATA supported the team with different focal points:

• AUCOTEC: Provided program-specific consulting and training to transfer the necessary expertise for using Engineering Base in the mobility sector. 
• ROTRING DATA: Handled project coordination, data preparation for database import, IT environment setup, ERP integration, and more. 

Based on their experience with the previously used document-based ECAD solution, users aimed to solve specific challenges more efficiently with the new software. Engineering Base proved to be a powerful collaboration platform with its object-oriented database approach. It not only simplifies the creation of electrical documentation but also meets critical operational requirements such as system integration (including ERP) and handling large volumes of supplier components.

“From a tooling perspective, our engineering setup now meets our own expectations. Not only have speed and quality improved significantly, but we were also able to adapt our organization – introducing assembly responsibility that reflects the new modularity.”

Pascal Ellenberger, Head of Mechatronics, Carrosserie HESS AG

Mit der Unterstützung von AUCOTEC und ROTRING DATA gelang es dem Team von HESS, die Systemumstellung trotz laufenden Betriebs erfolgreich durchzuführen. Heute verwenden zehn Beschäftigte Engineering Base in der Produktionsumgebung. Dadurch hat sich ihr Berufsalltag in mehrfacher Hinsicht verändert:

• Arbeitsmethode: Der Fokus liegt nun auf effizientem Engineering mithilfe einer zentralen Datenbank („einmal erstellen, mehrfach verwenden“), statt manuellen, repetitiven Aufgaben. 
• Qualität: Mit dem neuen Werkzeug gehört die manuelle Datenübertragung der Vergangenheit an. Das spart Zeit und verringert die Fehlerquote. 
• Architektur: HESS verfügt nun über eine modulare Elektrotechnik-Architektur, die sich durch eine hohe Wiederverwendbarkeit der Engineering-Bauteile auszeichnet. 

Da Engineering Base erst seit kurzer Zeit produktiv verwendet wird, lässt sich der endgültige Nutzen noch nicht eindeutig beziffern. Doch die Rückmeldungen der Beschäftigten machen deutlich, dass sich die Investition in die Umstellung trotz beträchtlicher Kosten gelohnt hat. Wie bei konventionellen Support-Vereinbarungen üblich, gehen AUCOTEC und ROTRING DATA allmählich von einer intensiven Betreuung zu einer punktuellen Unterstützung über.

Durch den Umstieg ist Carrosserie HESS AG heute gut gerüstet, um Innovationen im öffentlichen Verkehrswesen nachhaltig voranzutreiben.