Traction Control Strategy

How it works: Traction Control Strategy

Discover how your traction control system works with the 3D – Intelligence technology.

GRIPONE traction control systems include several control strategies. All of them are connected to the 3D-INTELLIGENCE and each one works following a specific philosophy.

When we speak about traction control, we speak about spinning. At first we have to define the meaning of this word: “spinning”. The spinning define the percentage of sliding of rear tyre compared to the front tyre. Mathematically the spinning is defined by the following formula:

Spinning = (rear speed – front speed) / rear speed

When the motorcycle is straight, its real speed is the one measured at the front tyre. The rear tyre can turn at same speed (and in this case the spinning = 0) or slide a certain percentage. If for example the speed measured at the front tyre is 90kmh and the speed measured at rear tyre is 100kmh, we can say that the spinning is 10%. The rear tyre is sliding and it is loosing performance.

If we want to describe the traction control strategy in few words, we can say that the user can fix a target of spinning (in GRIPONE S3 it is rapresented by the parameter called SLIP TARGET) which is the maximum spinning allowed to the rear tyre. When the spinning of rear tyre is greater than this value, the strategy start to reduce the power. When the spinning of rear tyre comes back to normal (under the value of SLIP TARGET) the strategy stop to reduce the power. The reduction of power is proportional to the difference between spinning and SLIP TARGET. It means that as much greater the difference between these values and the greater the reduction in power.

Itself the strategy of traction control looks quite simple but the reality is a bit more complicate. The system uses a “target” to estimate the safe amount of spinning of rear tyre. The target value, used from traction control system, is not fixed: it change 200 times per second, based on many parameters like tyre load, leaning angle, speed, drag force. The 3D-INTELLIGENCE elaborates signals from speed sensors and from the inertial platform IMU to estimate the dynamic condition of the bike (like leaning angle, load on tyre, drag, etc.) and gives the informations to the traction control strategy. The strategy itself uses the informations to change properly the target value.

The target value changes according to the condition of the motorcycle. Of course a certain amount of spinning is not dangerous when the bike is straight (upright) but it could be dangerous if the motorcycle is fully leaned (in middle of the corner). When the conditions make the value of spinning dangerous, the target drops down. When the conditions make the value of spinning  useful to accelerate, the target value increases. In this way to estimate the amount of spinning that the rear tyre can accept, the performance of the bike is always safe and close to the best.

On the other hand, for the user it is very easy because he needs just to fix an “average” level of SLIP TARGET. GRIPONE takes care about all the rest, calculating the variation of target of spinning according to the dynamic condition of the motorcycle.

How it works: Launch Control Strategy

Find out how your system works with the 3D – Intelligence technology.

GRIPONE include several control strategies. All of them are connected to the 3D-INTELLIGENCE control system, but each strategy works following a specific algorithm.

If you want to describe the launch control strategy in few words, you can say that the user fix a target value of wheelie (during the launch). When the wheelie of front tyre is bigger than this value, the strategy start to reduce the power. When the wheelie of front tyre come back to normal (under the value) the strategy stop to reduce the power.

The strategy of launch is the simplest one but the calculation of real vehicle speed is the most complex because when the speed of bike is close to zero (0) the difference between front speed and rear speed could be big (and this make the algorithm very unstable). The real vehicle speed is used to estimate the wheelie level like in the wheelie control strategy. When the level of wheelie is over the target value, the strategy start to reduce the power. When the level of wheelie is under the target value, the strategy stop to reduce the power.

The real vehicle speed is one of the most complex calculation into the GRIPONE strategies. A very accurate value come from the correct initialization of inertial platform. Without the inertial platform IMU the estimation of real vehicle speed could be not that good (even if the system can work nicely even without IMU).

 

Wheelie Control Strategy

How it works: Wheelie Control Strategy

Discover how your anti wheelie system works with the 3D – Intelligence technology.

GRIPONE include several control strategies. All of them are connected to the 3D-INTELLIGENCE control system, but each one works following a specific philosophy.

The wheelie, in addition to being spectacular, is important if you want to get maximum acceleration when you exit from a curve. When using a motorcycle with a lot of power, when coming out of the corner, the longitudinal acceleration (that along the axis of movement of the bike) transfers all the weight on the rear wheel to the detriment of the load of the front wheel.

The acceleration limit is represented by the detachment of the front wheel from the asphalt. The best possible acceleration is achieved when the front wheel is slightly raised off the ground and when the bike does not change its pitching angle. For this reason the anti wheelie control is very important to optimize the acceleration out of the corners.

The speed detected at the front wheel does not always represent the actual speed of the motorcycle. In fact, when the bike wheelies, the speed measured at the front wheel decreases while the speed measured at the rear wheel increases. This divergence of speeds, together with other information coming from the inertial platform, makes it possible to define the level of wheelie of the motorcycle and keep it under control.

If we want to describe the anti wheelie control strategy in few words, we can say that the user fix sensitive of the system to detect the wheelie. When the wheelie is detected and too big, the strategy start to reduce the power. When the wheelie of front tyre come back to normal (under the value) the strategy stop to reduce the power.

Itself the strategy of anti wheelie looks quite simple but the reality is much more complicate because it is quite difficult estimate the real level of wheelie. GRIPONE together with 3D-INTELLIGENCE estimates a “motorcycle real speed”. This real speed is not the speed measured from the front wheel because it drops during the wheelie. As well it is not the speed measured from the rear wheel, because it is bigger then real speed (due to the spinning). Only when the “motorcycle real speed” is calculated properly, the anti wheelie strategy can calculate the level of wheelie. By the user input (that fix a certain sensitive) GRIPONE compare the amount of wheelie and decide if reduce the power or do not reduce the power.

The real vehicle speed is one of the most complex calculation into the GRIPONE strategies. A very accurate value come from the correct initialization of inertial platform. Without the inertial platform IMU the estimation of real vehicle speed is not that good.

3D Intelligence

3D Intelligence

Discover how our systems work with 3D-Intelligence technology.

3D-INTELLIGENCE is the heart of the GRIPONE systems. The general traction control systems activate a proportional power reduction when the sliding or the wheelie is over a certain value (defined by the user). With GRIPONE instead matters are a bit more elaborate!
The bike provides data (coming from the speed sensors, the motor and the inertial platform) that are processed from the INPUT MANAGER. The INPUT MANAGER combines the data and obtains as a result other physical quantities (such as the roll angle, the lateral acceleration or the wheel load and others) which serve to establish the dynamic condition in which the vehicle is located.
The condition of the vehicle is then managed by VEICHLE DYNAMIC MANAGER, the most important block of GRIPONE system. The condition of the vehicle is treated as a coordinate in a four-dimensional space. This coordinate is inserted inside of the so-called “ellipse of adherence”, that is the safe zone within which the rider can stay. If the dynamic state of the motorcycle exits the area bounded, it is defined a “error”.
The error is sent to another block called POWER MANAGER. This, according to the type of engine, provides (as result) a proportional power reduction, able to help the pilot to go back inside the safety zone.

Here’s how to figure out the real difference between our systems! Both the GRIPONE CHRONO TC and GRIPONE S3 include within them almost the same blocks for the calculation of the intervention on the bike (except for the Traction Control Auto Correction included into GRIPONE S3). The substantial difference lies in the way in which the user can act on all the configuration parameters.
The GRIPONE CHRONO TC is the result of intensive work of aging. Only a few basic parameters (by which you can manage the operation of the system) are visible to the user. The system then combines these few parameters to automatically generate all control parameters (30 in total) necessary to the VEICHLE DYNAMIC MANAGER. For the user it is easy to manage the system because it must only increase or decrease the intensity of the control that want to change (such as the traction control). If the user needs more control into the corner, he increses the traction control of one step. The unit, with a “cascade system” decides to adjust every single parameter involved into the traction control strategy to get what the user wants. From other hand the system has some kind of limitations in terms of personalization.

With GRIPONE S3 the user has access to all configuration parameters. It is as if the user could write directly inside the VEICHLE DYNAMIC MANAGER. This offers great potentialities, making the system extremely flexible. On the other hand it can become difficult to maintain control and easy “lose the way”, by changing one of the parameters in the wrong way.

Of course it is understood that the system GRIPONE S3 offers other advantages and additional options such as the ability to connect the DAM data acquisition and manage additional strategies (such as the PIT LIMITER and QUICK SHIFTER). Anyway the strategies of power control (traction control, anti-wheelie and launch control) work in the same way on both systems GRIPONE S3 and GRIPONE CHRONO TC. The biggest different for GRIPONE S3 is the AUTO CORRECTION system for traction control. Even if the user loads a map with a sensitivity not suited to his riding style, the system will be able to correct yourself. Relatively in a short time frame (equivalent to a 3-4 laps of circuit, more less 15km) GRIPONE S3 calculates the ideal sensitivity, depending on how the rider is using the bike and optimizes it. At each stop the system will take note of the differences (from sensitive of loaded map and the correction) and it will replace the Map has been loaded with the optimized independently. Without any modification from the user, the GRIPONE S3 will be able to optimize the setup.