Case Study OnEfficiency.SmartAccelerate: more efficient and economical thanks to digital solution from Voith
Voith has recently introduced OnEfficiency.SmartAccelerate as part of the OnEfficency mobility solutions. The Voith subsidiary in Brazil is an important stakeholder in the development of the new software increasing city buses’ intelligence. What’s more, it offers operational optimization – without the need for specific driver trainings.
One of the first customers to test this software strategy concept is the bus company Gato Preto, which has been helping to shape local public transport in São Paulo for more than 80 years. It is a company whose core tasks include not only providing the population with a local transport system, but also continuously improving the processes, training and education of employees. Sustainability and protecting the environment plays a big role too – one aim is to reduce the amount of harmful emissions. As Gato Preto equips, maintains and repairs a fleet mixture of manufacturers including Mercedes-Benz, Volkswagen, Scania and Volvo, the company selected Voith to upgrade its DIWA.5 transmission with OnEfficiency.SmartAccelerate to consume less fuel and increase operational operational efficiency.
Smooth acceleration for greater energy efficiency
OnEfficiency.SmartAccelerate controls the acceleration of the vehicle. Fuel consumption can be reduced because it is no longer the driver alone who defines driveline output; the transmission control unit supports it in the context of the vehicle dynamics. The software upgrade also helps to save on bus maintenance costs, because the driveline is used much more gently. In addition, it minimizes CO2 emissions through greater energy efficiency. Furthermore, smoother acceleration reduces the necessity of hard braking and subsequently decreases the number of accidents in urban traffic. After all, pedestrians and other drivers benefit when buses glide along gently and become more predictable in their maneuvering.
“It is the sum of these benefits that led us to test DIWA automatic transmission with OnEfficiency.SmartAccelerate,” says Fernando Gatti Moroni de Padua Lima, Director of Viação Gato Preto. “One of our core competencies is to work on the continuous improvement of our processes to achieve greater fleet efficiency and positive effects, for example on fuel consumption and environment. Our initial experience confirms Voith's promises.”
Digital solution based on 25 years of experience
Voith supplies the new software concept in combination with the DIWA automatic transmission control system. “We developed OnEfficiency.SmartAccelerate based on the operational characteristics of city buses in Latin America,” explains Rogério Pires, Head of Voith Turbo Mobility Division in Brazil. “The 25-year track record of operational data we collected in this region enabled us to develop a software strategy that makes way for autonomously securing a more efficient vehicle operation.”
In addition to the experience gained from more than two decades of cooperation with vehicle manufacturers and bus companies, a large amount of data comes from the operation of buses for which Voith has tested the optimum acceleration behavior in simulations. Main input parameters are vehicle speed, topography and vehicle acceleration. In addition, there are auxiliary parameters like vehicle weight, tire size, transmission ratio, acceleration pedal position and further engine parameters. To this end, Voith engineers compared these values with the real routine that the buses cover every day in São Paulo and other South American cities. As a result, Voith can implement an optimal strategy for the driveline via the transmission software, which is based on significant data.
How OnEfficiency.SmartAccelerate works
Unlike today’s configuration that gives the driver full control of the maximum power of the bus, OnEfficiency.SmartAccelerate dynamically limits the maximal admissible engine torque depending on the actual surrounding parameters. Continuous monitoring of the actual driving performance enables dynamic adjustment of the power train, offering optimized configurations for each specific operating condition, while also making up for driving deficiencies or excesses in vehicle acceleration. The combined principle of continuously variable transmission (CVT) and conventional transmission results in lower frequency of gear shifts, higher efficiency and higher reliability.
The system combines the signals acquired from existing sensors in the Voith automatic transmission system with information from the CAN network to monitor the driver's commands and the vehicle’s dynamic behavior. OnEfficiency.SmartAccelerate limits the engine torque emitted via CAN in order not to exceed a given vehicle acceleration. To achieve this, the software update defines for each DIWA shift program a specific data map with the acceleration limit in relation to the vehicle speed range.
The logic and processing capacity of the transmission control module enables OnEfficiency.SmartAccelerate to manage the power train and therefore allows more efficient, safe and comfortable driving. “Due to domain knowledge in drive technologies and local public transport operations, we know which maximum power is needed in which drive situation. This results in a significant efficiency increase,” states Pires.
Initial pilot trials and customer deployments have had positive effects. The use of DIWA automatic transmission with OnEfficiency.SmartAccelerate reduced fuel consumption by an average of three to four percent. This also reduces the emission of climate-damaging carbon dioxide as well as material particles from engine and brakes.
The system is dynamic and operates regardless of existing load and topography conditions, and thus applying optimum settings for each specific operation. Simulation of best drivers can be achieved with dynamic monitoring of driver behavior and automatic adjustment for an optimum setup of the powertrain on each specific operational condition, independent of driving failures.
OnEfficiency.SmartAccelerate reduces the need for driver training, as the system operates whenever any acceleration condition deviates from its pre-set standards. This is confirmed by Voith customers:
“We are currently testing OnEfficiency.SmartAccelerate in part of our fleet under realistic conditions and assume that we will achieve significant savings through the software update alone,” says Fernando Gatti Moroni de Padua Lima. “One of the decisive factors for success, however, is the concept of starting with driving behavior optimization without restricting the drivers themselves. This saves us time-consuming training and further education that would hardly make sense from a business point of view.”
Upgrading public transport – with intelligence made by Voith
“The upgrade with software is a real paradigm shift,” says Rogério Pires. “The difference in bus performance and fuel consumption is not only due to powerful hardware but also to intelligent software that makes operation much more efficient and offers room for further improvements based on the existing hardware.”
With OnEfficiency.SmartAccelerate, Voith provides an efficiency upgrade based on a software approach. This accurately reflects the opportunities that digitalization offers: The added value of products increasingly results from the embedded intelligence. In addition, a software solution proves to be very flexible, as OnEfficiency.SmartAccelerate can be retrofitted to many released vehicles with Voith DIWA transmissions in Euro 5 engines and up.
There is yet another advantage of this concept that is relevant for customers over the long term: Voith gains new flexibility in equipping the DIWA automatic transmission with new functions that are data-based and make scenarios from the Industrial Internet of Things or using artificial intelligence possible.