While electronic stability control has become mandatory equipment for cars sold in the U.S. because of the huge reduction in crashes it provides, motorcycles are a category of vehicles that can benefit even more than four-wheeled vehicles because of their propensity to fall over when riders make mistakes or encounter problems.
As happened in cars, electronic safety technology for motorcycles is tracing a course starting with anti-lock brakes, continuing through traction control, and arriving eventually at full electronic stability control.
Anti-lock brakes have been available for decades on premium motorcycles, and very high-powered race-replica sportbikes have in recent years introduced traction control. Now, finally, comes true motorcycle stability control (MSC).
Bosch has introduced an add-on MSC module for its existing ninth-generation motorcycle ABS system that carries accelerometers that measure yaw and pitch and the necessary programming to modulate engine power accordingly.
ABS alone is good for a 37% reduced likelihood of involvement in a fatal crash, according to the Insurance Institute for Highway Safety. It also reduces the incidence of insurance claims by 22%, they said.
Relatively few bikes have ABS and, until the new Ducati 1299 Panigale and Multistrada 1200 and the KTM 1190 Adventure reach showrooms, none has MSC. As a result, while automotive traffic fatalities have been steadily falling, motorcycle fatalities are rising.
“It is a troubling trend,” said Anne McCartt, Senior Vice President for Research at IIHS. “As the number of new riders continues to increase, though, it’s becoming more important than ever to lower the crash risk.”
Enter Bosch’s new MSC system. While ABS can apply full braking at lean angles of no more than 20°, helping avoid mostly straight-line crashes, the added intelligence of the MSC system supports automatic threshold braking at lean angles as steep as 45°. And because it can automatically brake both wheels at maximum, the MSC system reduces the tendency of hard front-wheel braking to stand the bike upright in the turn and push it off course.
“The Bosch inertial platform makes the 1299 Panigale better because it allows the bike’s electronics to more accurately and comprehensively adjust its performance,” noted Paul Ventura, 1299 Project Manager for Ducati. “Electronics are a crucial part of modern motorcycles,” he said. “Without question, they make the bikes faster, safer, and more rider-friendly.”
Bosch says that 24% of motorcycle crashes occur in curves, which gives the MSC system the ability to assist in situations when ABS can’t. While ABS is able to prevent about 35% of crashes involving casualties, MSC adds another 6% to that, for protection in 41% of such crashes, said Frank Sgambati, Director of Marketing and Product Innovation for Robert Bosch LLC’s chassis control systems division in North America.
Bosch’s MSC system includes the ABS module, with its hydraulic pump, electric motor for the pump and electronic control unit to run the system, plus the wheel speed sensors that identify lockup or wheel spin.
“By taking the next step, we’ve added yaw and pitch sensors that allow a bit more information,” Sgambati said. “If you are in a panic situation in a bend or curve and grab a handful of brake, it is able to determine the lean angle of the motorcycle. Using sensory input, it will determine if the bike is tending to try to go off the road and using brake modulation it will try to slow it down, and work with the ECU to slow engine torque so the bike remains stable.”
“Using an Inertial Measurement Unit, the Bosch system determines the bike’s dynamic position at all times, for example precisely calculating its angle of lean,” said Ventura. “This allows the use of cornering ABS, which dramatically increases safety by allowing the rider to brake without crashing even while deeply leaning.”
Similarly, the system is able to intervene in case the rider breaks traction by applying too much throttle rather than too much brake. “The system does allow it to reduce engine torque,” Sgambati said.
“It also allows wheelie control, which mitigates front-wheel lift for maximum forward acceleration while staying under control,” Ventura reported. “And on the S version, the IMU interfaces with the Ohlins suspension to continually adjust its settings for the best possible performance.”
The ninth-generation ABS module that is the foundation of the MSC system is Bosch’s first that was designed from the outset exclusively for motorcycle use, rather than being derived from an automotive module, according to Sgambati. As a motorcycle-specific product, this ABS module is smaller and cheaper than previous editions. If future versions additionally incorporate the MSC features into the ABS module so there are no external add-ons, that could help reduce the system’s hardware cost further, he said.
Software is another matter. The algorithms overseeing keeping the rubber in contact with the road is specific for each model, so there is always a software development cost associated with adding MSC to a new model, Sgambati reported.
“The recommendation is that [software development] should be part of the bike’s development process,” he said. “You are using algorithms developed specifically for the bike and the tires it uses.”
A key aspect of the system is that it must not interfere with riders’ enjoyment of their motorcycles. “The draw for motorcycle riding is the excitement,” Sgambati noted. “We don’t want to interfere or change that experience. We only want to appear in panic situations.”
However, with mistake-prone beginners commonly starting out on more affordable entry-level machines, it seems as though the riders who could most benefit from MSC are the least likely to have motorcycles equipped with it. This is something Bosch hopes will change.
“As we go forward with scalability, we have pretty good confidence that more low-end bikes will see ABS and MSC,” he said. The question is how soon that can happen. “What we hope is soon,” Sgambati said.
Though Ducati specializes in premium bikes, Ventura said he also thinks stability control will reach more affordable models. “An electronic improvement like the Bosch system should absolutely trickle down to other models, especially as its cost decreases,” he said. “For now, it’s been introduced on Ducati’s highest-performance, highest-technology motorcycles like the 1299 Panigale and new Multistrada 1200, but just like ABS became in the past and traction control is becoming now, inertial electronics will become ubiquitous in the future.”