Frankfurt – October 31, 2026 -- Fractions of a micrometer in grinding now decide the efficiency and noise level of electric vehicle drivetrains, and machine builders are answering with sub-micron surface finishing and digital twin process control. The topic is in focus at GrindingHub, organized by the VDW (German Machine Tool Builders' Association), which runs May 5-8, 2026 in Stuttgart.
Missing engine noise exposes gearbox flaws
Electric vehicles lack the masking sound of a combustion engine, so excitations from components such as the gearbox become far more audible, according to Prof. Thomas Bergs. He heads the Manufacturing Technology Institute (MTI) at RWTH Aachen and is a director at Fraunhofer IPT.
Geometric deviations on gear flanks transfer directly into the drivetrain as rotational vibrations. Bergs says a high-precision grinding process with minimal deviation is therefore needed to tune noise, vibration and harshness (NVH) behavior. At the high rotational speeds of electric drives, the entire tolerance chain matters. Microstructures on conventionally ground shaft sealing surfaces can cause unwanted leakage.
Digital twins predict roughness and residual stress during production
For highly loaded parts such as e-mobility gearbox gears, surface integrity largely determines service life. MTI is developing data-driven methods, based on a digital twin, to predict roughness and residual stresses. The approach links real-time machine sensor data with physical models, so part quality can be estimated during manufacturing and corrected immediately if needed.
Bergs names optimized process chains combined with polishing generating grinding as a promising route for gear production in electric transmissions.
Tolerances shrink to micrometer and nanometer range
Machine builders must deliver precision in the micrometer and even nanometer range. Human hair measures roughly 50 to 100 micrometers in diameter, while ultrafine exhaust dust at about 100 nanometers is up to a thousand times smaller.
United Machining Solutions, based in Bern, Switzerland, exhibits in Hall 9, Stand 9B50. CTO Christoph Plüss says the company's systems produce surfaces in the micro and submicrometer range, cutting noise and friction while holding consistent part quality in series production. He adds that precisely ground components reduce friction losses and contribute directly to range optimization.
Gradual shift in component mix drives investment caution
The range of drivetrain parts will change slowly over several years or even decades. The central commercial challenge for component makers is therefore targeted investment. According to Plüss, United Machining Solutions relies on flexible machine concepts and modular production solutions that adapt quickly to new requirements, supplemented by digital technologies for data-based process optimization.
Hybrid and electric drives that recover energy through regenerative braking add further demands on machining, as different materials, new geometries and combined functions must be processed at consistent quality.
Multiple powertrain types sustain demand for precision parts
Plüss expects battery-electric systems to coexist with optimized diesel engines, hydrogen combustion engines, hybrids and fuel cell technology in coming decades. Each drive type places specific demands on manufacturing and quality, which he says secures long-term demand for high-precision components. He also expects autonomous vehicle ramp-up to add requirements for precision, safety and system integration, and describes the outlook as offering lasting growth opportunities for manufacturing technology.