In mid June 2024, the annual EuroBrake conference was held in the German city of Mainz, with over 1100 delegates in attendance. As usual, the three days included a tightly packed technical program, and the conference venue hosted a large exhibition of braking technology from leading suppliers. In preparing the technical content, the programme development committee focus on the challenges and opportunities facing the braking world.
In reviewing the conference, it’s possible to offer some insights into where we, the braking industry, find ourselves, what immediate challenges we face, and what’s on the horizon for brakes.
With that in mind, it is fair to say that brake emissions remains the dominant topic in EuroBrake 2024. With a total of 23 separate technical sessions on the agenda, 10 of these were specifically addressing emissions. As well as that, an expert panel discussion and closing keynote considered the topic. It was also notable that the exhibition area was offering many solutions related to the measurement, control and supression of braking emissions, with many innovative approaches to friction surface management being demonstrated.
During the excellent Voice of the OEM panel discussion, the challenge of adopting all vehicles to the new Euro 7 requirements in time for the cut off was mentioned repeatedly. That some of the industries’ leading minds are fully engaged on this topic shows that while we may understand the size and shape of the mountain we have to scale, the ascent is still daunting.
A further highlight on the emissions topic allowed us to hear from the experts who are charged with shaping regulation across the globe. The specifics of emissions regulations across Europe and China were hightlighted, across a variety of land transport modes.
Brake Emissions solutions
The topic of brake emissions is a hot one. But it is fair to say the product of significant innovative efforts was on display at EuroBrake 2024. While research on the topic of Non-Exhaust Emissions was relatively basic at the first EuroBrake in 2012 (one Ford paper considered brake dust and it’s impact on customer satisfaction, and one paper on predicting rail brake emissions from KTH Sweden), significant research on the topic has been underway for over a decade. Brake particle emissions are understood to be the dominant vehicle emission source, even in a contemporary combustion powered vehicle, given how exhaust emissions are controlled. As such, legislative efforts have underlined a need to address brake emissions, and the braking industry has risen to meet the challenge.
During this year’s conference, 10 specific technical sessions gave the opportunity for presentation of multiple new technical solutions, ranging from physical dust collectors through friction surface improvements through to control algorithms to mitigate the most emmissive braking scenarios. The technical program also gave valuable insights into the next legislative frontiers on non-exhaust emissions, with significant attention on commercial vehicles presented from multiple global researchers.
Meanwhile, in the exhibitors area, the maturation and industrialisation of brake disc cladding techniques was clear to see. Many specialist companies exhibited their solutions for the application of wear-resistant friction interfaces, and some of the most prominent brake disc manufacturers focused their own messaging on emissions reduction solutions.
Emissions widened scope
While the advent of brake emissions controls has arrived for passenger cars, the topic is clearly of interest in a variety of new sectors, and on a wider geographic spread. During the first day of the conference, experts from Europe, USA and China spoke on regulartory frameworks in place in these juristictions.
In the case of China, the final legislation is still in development, with current discussion focusing on establishing a representative drive cycle, as well as timeline and outlook for introducing brake emissions restrictions in a number of vehicle classes.
In the same session, the EU perspective considered the implementation of brake emissions regulations for LDV and HGV. The path to LDV is clear; the introduction dates for M1 and N1 vehicles is defined, as well as the initial PN10 limits. However, other (heavier) vehicle limits are still being considered. We also saw the current activity on inter-laboratory testing, an essential element for implementing the Euro 7 program.
An interesting perspective from Japan was also presented, within a technical session. Here, the Japanese Automobile Research Institute presented insights on the overall emissions legislation in Japan, and the specific outlook for HGVs. Within this context, a novel study on a city bus (M3 category) operating in Toyko was presented, demonstrating that perhaps a one – size – fits – all approach may not be beneficial for HGVs.
Electro-Mechanical Brakes
2024 probably marked the first signs of mainstream development evidence for Electro-Mechanical Brakes. While the technology has been around for at least 3 decades, this year’s conference showed in-depth technical challenges and robust solutions being created to bring this technology into the mainstream. In previous years, it’s been apparent that EMB has an increasingly compelling technical and financial case for certain types of Commercial Vehicles. The regulatory framework to bring in the first EMB implementations is clear, and we can expect these systems to hit the streets very soon.
But on passanger cars, an important pivot has taken place, and it perhaps shortens the runway for EMB in this sector. Previously, the adaption of EMB in this space relied on a number of key vehicle infrastructres being already available before EMB could make a compelling financial argument (redundant power and comms, usually found on L4+ ADAS vehicles but not many others). As the prospect of significant volumes of L4+ vehicles remains stubbornly distant, offering a full EMB vehicle in this space seemed just as distant. However, a strategy of a wet front axle and a dry rear axle seems to be gaining momentum, and will allow for EMB systems to make their mark in passanger cars a lot sooner than might otherwise be expected. Advantages for such an architecture include lower unit cost thresholds and fitting neatly within existing regulatory frameworks.
A final word on this topic must include a prominent EMB supplier in this space – Figure Intelligent Technology Co. They made a significant contribution to the EMB technical session and poster session, as well as a prominent exhibition stand with excellent technical displays (kindly and patiently explained by knowledgable technical and sales people).
Artificial Intelligence
Artificial Intelligence made a significant impact on the EuroBrake 2024 conference. One of the opening Keynote sessions gave an overview on data science approaches to braking topics, and some examples from existing solutions in the brake NVH sphere. The importance of well prepared data, and the potential value of harnessing that data was laid out in clear terms (terms such as data moor and my personal favourite – dark data).
On the second day, a Strategy Panel discussed the impact of big data on our industry, with contributions from OEMs, Tier 1 suppliers and significant players in the academic world.
For the first time, a specific technical session was devoted to AI usage in brakes development, with 5 technical papers. Several papers considered the use of data science in predicting brake emissions, considering either material preparation or driving conditions as inputs and brake wear or emissions metrics for outputs. These Machine Learning approaches may lay the building blocks for future brake control systems to better minimise unwanted brake emissions (both particulate and noise). Rounding out the session, an interesting overview of the usage of ML in the various advanced driver assistance and autonmous vehicle sphere was presented. Here, insights into the sheer amount of data generated in vehicles, and the importance of ML in increasing numbers of vehicle systems was highlighted.
A final reflection on the topic of AI in Brakes relates to the exhibition area. Despite the relative importance of the topic, there were no specialist AI vendors in attendance.
LCA and carbon footprint
The final interesting theme of EuroBrake 2024 was that of Life Cycle Analysis. This topic considers the resource usage of a part or system not just during it’s primary usage, but from cradle to grave, or more likely from mine site to recycling facility. The topic had a very interesting technical session, and came up repeatedly in the Voice of the OEM strategy panel discussion.
From an OEM perspective, the car maker will likely have a strategic vision, such as to signficantly cut their carbon footprint, or be carbon neutral by some future date. And while a change in the fleet powertrain can help during the life of the vehicle, even the most successful EV maker has to consider where their raw materials come from, and what happens after the vehicle’s life.
To fully understand LCA, we must consider emissions scopes Scope 1, Scope 2, and Scope 3 emissions are categories defined by the Greenhouse Gas (GHG) Protocol to measure and manage an organization’s carbon footprint.
Scope 1 emissions are direct GHG emissions from sources owned or controlled by the organization. These include emissions from stationary combustion (e.g., boilers, furnaces), mobile combustion (e.g., company vehicles), industrial processes, and fugitive emissions (e.g., leaks from refrigeration systems).
Scope 2 emissions are indirect GHG emissions from the consumption of purchased electricity, steam, heat, and cooling. These emissions occur at the facility where the energy is produced, not where it is used. For example, if a company buys electricity from a coal-fired power plant, the emissions from burning coal are Scope 2 emissions for the company. Managing Scope 2 involves increasing energy efficiency and sourcing renewable energy.
Scope 3 emissions encompass all other indirect emissions in an organization’s value chain. This includes upstream emissions from the production of purchased goods and services, employee commuting, business travel, and waste disposal, as well as downstream emissions from the use of sold products and end-of-life treatment. Scope 3 emissions often constitute the largest portion of a company’s carbon footprint. Reducing these emissions requires collaboration with suppliers, improving logistics, and designing more sustainable products.
In terms of brakes, we can consider the brake particle emissions reductions as Scope 1 emissions, and we can consider the creation of the braking components in the vehicle as Scope 2. Scope 3 is the most significant, but here the End-of-Life of our braking components is critical. The classic approach to friction braking means we plan for our components to degrade over time, and after a certain amount of wear during service, we must replace these components. Approaches to enhance the recycling of brake components, such as that used by Green Friction, can lead to significant reuse of base materials, which can greatly accelerate the OEM’s sustainability journey.
As usual, EuroBrake 2024 offered important insights into today’s mobility challenges, and tomorrow’s braking opportunities. Euro 7 is still a crictical topic, but several new trends are finding their niche, and it will be fascinating to see which of these come to the fore in the coming years.