Electronic suspension


Electronic suspension refers to vehicle suspension systems that use electronic sensors, actuators, and control units to adjust damping and preload characteristics dynamically. Found on both motorcycles and automobiles, these systems enhance ride comfort, handling precision, and stability by adapting suspension behaviour to road conditions and rider or driver input.

Overview

Traditional suspension systems rely on mechanical or manually adjustable dampers to control rebound and compression. Electronic suspension introduces real-time adjustability through electronically controlled valves, servomotors, and microprocessors. These systems can modify suspension stiffness or height in milliseconds to respond to changing speed, load, or terrain.
Electronic suspension technology was first applied to production motorcycles in the 1980s and 1990s, with early examples from Yamaha and Honda. Modern systems integrate data from wheel sensors, accelerometers, and inertial measurement units to make constant adjustments.

Principle of operation

Electronic suspension systems operate using three main elements:
  • Sensors - monitor parameters such as wheel speed, pitch, acceleration, and suspension travel.
  • Control unit - processes sensor data and determines optimal damping or preload settings.
  • Actuators - adjust hydraulic or electromagnetic valves in the suspension to modify damping force.
In motorcycles, the control logic often links with ride modes or traction control systems. In automobiles, it may interface with steering and stability control systems.

Types

Electronically adjustable suspension

Early systems such as BMW’s ESA II and Honda’s HMAS allowed the rider to choose preset damping or preload settings via handlebar switches. The suspension remained mechanically passive but could be electronically tuned.

Semi-active suspension

Semi-active systems, such as BMW’s Dynamic ESA or Ducati’s Skyhook, adjust damping continuously in real time based on feedback from sensors. These systems maintain mechanical springs but control hydraulic flow through solenoid valves.

Fully active suspension

Fully active suspension can generate vertical movement independently of road input using hydraulic or electromagnetic actuators. Although common in high-performance automobiles, such systems are rare in motorcycles due to packaging and power constraints.

Applications

Motorcycles

Electronic suspension is widely used on premium and performance motorcycles, including:
The systems typically allow riders to switch between "Comfort," "Sport," or "Dynamic" modes and automatically adjust preload for passenger or luggage loads.

Automobiles

In cars, electronic suspension is used for ride comfort and handling optimization. Examples include:
Advancements in sensor fusion and artificial intelligence are leading to predictive suspension systems capable of reading the road ahead using radar or camera inputs. These technologies are being tested in both automotive and motorcycle applications, aiming for fully adaptive systems that anticipate terrain changes.