Transductores de par de rueda de última generación para medir la resistencia a la rodadura en vehículos comerciales

Winterthur, junio de 2026 – Las mediciones de la dinámica del vehículo y la resistencia a la marcha no solo revisten gran importancia en el ámbito de la investigación y el desarrollo. Los vehículos comerciales deben cumplir una norma específica de emisiones de CO₂ para poder matricularse en la Unión Europea. A la hora de determinar los niveles de emisión, hay que tener en cuenta una amplia gama de factores, incluida la medición obligatoria del par de tracción. Con la serie de transductores de par de rueda (WTT) RoaDyn P1, disponible para vehículos comerciales ligeros (camiones pequeños) (ST), camiones medianos (MT) y camiones pesados (HT), Kistler realiza una valiosa e indispensable contribución en este ámbito.

El transductor de par de rueda RoaDyn P1HT está diseñado para vehículos pesados (HDV) y tiene un rango de medición de 50 000 N·m (rango alto) o 5 000 N·m (rango bajo); lleva varios años siendo una parte integral de la investigación y el desarrollo de camiones y autobuses. El transductor de par de rueda RoaDyn P1(ST/MT/HT) ha sido objeto de un rediseño fundamental y de modificaciones significativas, lo que se traduce en una fiabilidad aún mayor y una vida útil más prolongada. La rueda de par también está disponible para vehículos comerciales ligeros, camiones medianos y autobuses, con la configuración y el rango de medición adecuados.

En una rueda de par P1HT se han instalado seis células de carga piezoeléctricas de precisión de un solo componente, cada una de las cuales contiene dos sensores de fuerza piezoeléctricos. Se han optimizado los sensores de fuerza, se ha simplificado el cableado de las células de carga y se ha mejorado la protección de la carcasa frente a los efectos de las condiciones meteorológicas, la suciedad y la corrosión. Todas estas medidas se basan en la experiencia práctica y en las exigencias cada vez mayores del sector.

Existing wheel torque transducers can be upgraded thanks to their modular design

The further development of the RoaDyn P1ST/MT/HT wheel torque transducers has been designed so that existing torque wheels can be upgraded with the new components. Users can rely on maximum compatibility. Existing customers do not need to replace the entire wheel force transducer. The load cells currently installed will simply be replaced with the new components and optimized cabling; no reconfiguration is required. Kistler offers its customers the upgrade as a special service, thereby ensuring maximum sustainability and investment protection. A less complex design not only increases reliability and service life, customers also benefit from lower costs compared to a completely new investment. Effective immediately, only the advanced technology will be used.

Focusing on rolling resistance measurements according to the EU CO₂ Emission Regulation

In addition to typical applications such as research and development in the field of dynamic control systems, determining powertrain efficiency, measuring vehicle performance or analyzing fading effects in brakes, the wheel torque transducer is a key component in determining the CO₂ emissions of light, medium and heavy-duty commercial vehicles. Since 2025, stricter guideline values have applied to commercial vehicles over 3.5 tons on the basis of the EU’s CO₂ Emissions Regulation, which will be further tightened in a next step in 2030. To determine the CO₂ emissions, measured values for air resistance (Cd x A), the rolling resistance coefficient (RRC), engine performance maps, transmission and powertrain characteristics as well as axle and rotational inertia are recorded.

Within these measurements, the determination of the operating loads of a vehicle acting on a wheel torque transducer such as the RoaDyn P1ST/MT/HT while driving is of great importance. Finally, the CO₂ emissions are calculated from the measured values using the EU's standardized "VECTO" (Vehicle Energy Consumption Calculation Tool) calculation model. Manufacturers have a strong interest in component testing, as the precise measurements often yield values that exceed the standard values that would otherwise be used. The RoaDyn P1ST/MT/HT wheel torque transducers are the manufacturers' preferred choice for these mandatory tests. In contrast to other technological approaches, they do not require complex brackets on the outside of the vehicle body, which also increase the flow resistance of the vehicles and can lead to a falsification of the measurement results.

Measuring traction torque via telemetric signal transmission

Like all torque wheels of the flexible P1 series, the RoaDyn P1ST/MT/HT wheel torque transducers are quick and easy to install and can be replaced if necessary. The respective torque wheel replaces the center section of the rim, which is the most effective position for recording torques and at the same time offers optimum integration in the vehicle's chassis system. The traction torque My is measured using piezoelectric quartz sensors. The electronics integrated in the wheel torque transducer amplify and process the signals. In addition, these torque wheels each have four channels for temperature measuring elements. The data is transmitted wirelessly using the KiRoad Wireless P1 data transmission system, the receiver of which can be positioned inside the vehicle. For further processing, this system can be connected to the KiDAQ from Kistler or any data acquisition system (DAQ system) from other manufacturers. The new RoaDyn P1 series wheel torque transducers are extremely versatile and indispensable for research and development, certification and testing.

Patented technology

Kistler holds a patent for the piezoelectric precision load cell for determining torques on wheels. Among other things, this further development means that this patented load cell delivers even more reliable, high-precision results thanks to the greatest possible protection and technical simplification.