Bosch Develops Run-Flat ESP

Bosch, in collaboration with Michelin, has enhanced some of the traditional functions of its Electronic Stability Program, adapting them to work in conjunction with run-flat tyre technologies. The new cluster of enhanced ESP functions is called “Run-Flat Stability Control” (RFS). RFS contributes to maintaining the maximum level of driving safety and mobility even after a loss of tyre pressure.

In the event of a loss of pressure on one or several tyres, Run-Flat Stability Control significantly reduces the risk of understeer or oversteer. If the car does not respond to the driver’s steering actions, ESP initiates braking interventions on individual wheels and reduces the engine power. In the event of heavy understeer, the system reduces the car’s speed as quickly as possible by applying braking to all the wheels. It prevents the car from swerving and is very useful at motorway exits or for sudden lane changes. According to the company, the result is that drivers can RFS enabled vehicles more easily even during braking manoeuvres on surfaces with different coefficients of friction. “This is a result of the joint efforts of both companies and underlines their joint commitment to making motoring safer,” says Klaus Meder, executive vice president at Bosch Chassis Systems Control, where he is in charge of the development of brake control systems.

“For Michelin, ESP plus RFS opens up new avenues of further innovation on run-flat technologies,” explains Pedro Costa, vice president for continued mobility at Michelin. “For vehicles equipped with ESP plus RFS, we will design run-flat solutions with greater performances: for example, we can optimise the run-flat support ring of PAX System or the reinforcement of the sidewalls in case of Michelin ZP self-supporting tyres. We believe ESP plus RFS will accelerate the broad-scale deployment of run-flat technologies.”

Bosch and Michelin established the Paris-based “Innovations in Safety Systems” 50-50 joint venture in 2002 in order to pool their efforts at further optimising the interaction between tyres and brake control systems.