Innovative Suspension Technology
Semi-active Suspension Technology was first introduced in 2013 by Ducati Multistrada and BMW S1000 and now is rapidly taking the Motorcycle World by Storm! To understand why this suspension has been named semi active, we should first understand Adaptive and Active Suspension.
Adaptive Suspension Systems
Adaptive Suspension Systems use springs and dampers that allow the rider to quickly switch between a soft or firm ride to match changing road conditions.
Active Suspension Systems
Active Suspension Systems were first developed by Lotus in the 1980s for Formula 1 cars and make use of electromagnetic or hydraulic rams to actively control the wheels position.
In a true active set-up, there’s no spring or damper – the suspension is simply moved, usually by hydraulics, to ride seamlessly over bumps.
Active Suspension system uses sensors and microprocessors to monitor the road beneath its wheels in real time. The system replaces the spring and damper with a hydraulic or electromagnetic actuator to control the wheel.
A computer reads the data that is sent by the sensors to an actuator that raises and lowers the shocks and springs to create a smooth riding experience.
So What’s the Difference?
In Simple Terms: The Adaptive Suspension System is a conventional suspension setup, where the ground pushes the wheel up and the spring pushes it down; in an Active Suspension System, the actuator controls the wheel movement by literally lifting the wheel over bumps or pushing it down into dips, which keeps the bike at a smooth, steady altitude.
Now Meet the Suspension Revolution
The Semi-active Suspension System makes use of an electrically controlled damping rod inside the forks and shocks along with the springs to adjust the damping. These systems can make changes up to 1,000 times per second.
Semi-active suspension is a type of automotive suspension system that controls the damping force of the shock absorber in response to input from the continuously varying road surfaces.
Why is it called Semi-active?
Although electronically-adjusted semi-active suspension is all the rage at the moment, it’s not true active suspension.
It still uses conventional springs and dampers, while only altering damper settings.
Semi-active changes the damping rate rather than raise/lower the bike as an Active Suspension does!
This makes it adaptive, by changing to suit the bike’s response to the way the suspension is moving, but not truly active.
For this reason it is named Semi-active.
In a Nutshell
The Semi-active Suspension sends data from sensors to a control unit (dynamic damping control unit), which processes the data to provide optimal damping for every possible riding condition.
2010-2012 Ducati Multistrada 1200S TTX Ohlins Rear Shock: Example Semi Active Suspension on eBay.
Performance and Benefits
- suspension is controlled at any input, even controlling the damping at low speed
- a response time of 6 milliseconds
- part of the assembly inside a magnetic solenoid moves, opening and closing a valve which controls the oil flow through the piston and through the rod
When moving from standing still, the dynamic damping control unit analyzes data to determine the rate of acceleration. At that instance the weight transfer is not rapid so the dynamic damping control unit opens the electrically actuated damping slowly.
Twisting the throttle will transfer weight to the rear resulting in compression of the rear shock.
Too much compression prevents achieving the best acceleration, so the control unit increases the compression damping on the rear shock, resulting in a stiffer setup.
As you decelerate and settle into a constant cruising speed, the control unit decreases the compression damping.
During cornering the control unit analyzes the data to determine the lean angle as the lean angle increases the contact patch between the tire and the road becomes narrow so it is very important to keep the tire sticking to the ground.
Stiff suspension setup will cause the motorcycle to jump around on every little bump on the tarmac, so the control unit reduces the compression and rebound helping the tire to stick to the ground.
When you change the direction from one corner to the opposite, the control unit takes into account the shifting weight of the motorcycle and consistently adjusts the compression and rebound damping stabilizing the motorcycle.
Having optimal braking efficiency is one of the most important aspects of motorcycle performance.
In order to stop at the shortest distance possible, maximum braking force should be transferred into the tire.
But with a lack of proper compression damping on the front forks, some of the braking force produced will be lost.
To solve this problem the Control Unit analyzes the data from ABS control unit to determine the rate of deceleration.
This helps the control unit to perform the optimal compression damping on different folks for maximum braking performance.
Hungry for More Innovation….
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Thank you for visiting Haul N Ride. Dave