On-line estimation of vehicle mass and its distribution
The behavior of a vehicle radically changes according to its current mass, given by the sum of the curb weight and carried load, and to its distribution among the various axles or wheels. The proposed method allows to calculate the actual vehicle mass and its distribution among wheels in real-time while the vehicle is running. This quantities can then be used to adapt the vehicle to the current working condition.
The more the vehicle actual mass differs from the reference condition, the more the dynamic vehicle behavior will change, together with comfort, fuel consumption, effectiveness of active safety systems, etc… Moving toward an intelligent vehicle having more and more active and adaptive controls, the actual vehicle mass becomes an important control variable: knowing it, it would be possible to adapt the vehicle to the current condition by means of brake management systems, stability controls, energy management systems, etc… The algorithm disclosed by this invention allows to obtain the actual vehicle mass and its distribution on wheels using variables already available on vehicle electronic control units (ECUs) and by knowing, with a good accuracy, the actual inflation pressure of the tires (through accurate direct TPMS). The calculation process, based on two iterative blocks each providing input to the other, exploits a-priori knowledge about tire specifications, which generally will be different from tire to tire.
- Provide inputs to on-board systems such as the ABS/ESP, central tire inflation systems, adaptive suspensions, engine and ADAS;
- Alert the driver in case of overload of one or more tire and/or improve TPMS functionalities;
- Provide the correct tire inflation pressure.
- The proposed method improves – with respect to the known art – the estimation of the total vehicle mass and its distribution on wheels;
- The goal of this patent can be reached without adding any dedicated sensor or other hardware components on-board.