When anticipating the occurrence of oversteer, VDIM prompts VGRS to provide an additional counter-steer steering angle, a split second before the yaw moment reaches a threshold level. If the oversteer persists, VDIM will command the by-wire braking system and hybrid system's torque output to bring the vehicle back to its original trajectory.


In eminent understeer situations, it starts by providing an additional steering angle and torque assist to the inside of the corner - this is done with the purpose of alerting the driver of the situation. If this proves to be insufficient to avoid understeering, VDIM will also prompt the brakes and powertrain to control the vehicle's yaw moment. Simultaneously, if the driver attempts to turn the steering too much to the inside of the corner, VDIM will limit that through VGRS and EPS, so that the front wheels retain their grip.

When cooperating with VDIM, VGRS can provide up to 3 degrees of additional steering input, effectively assisting the driver in the application of steering wheel input appropriate to the situation and, hence, helping to maintain vehicle stability.


Electronically Controlled Braking (ECB)

Via powerful, 334 mm ventilated discs to the front and 310 mm ventilated discs to the rear, fitted with high friction coefficient brake pads to further increase stopping power, a sophisticated, Electronically Controlled Braking (ECB) system facilitates the interaction of all the other brake control systems, in a way not possible with a conventional, fully hydraulic brake system.

In addition, as the driver removes the foot from the throttle, ECB acts in anticipation, automatically placing the brakes in standby mode by bringing the pads as close as possible to the discs for the most prompt response to pedal operation.

As fitted to the new GS 450h, ECB not only improves overall ehicle braking performance, but also facilitates improved brake energy regeneration for the hybrid system's battery recharging. The system operation employs a combination of hydraulic braking power and regenerative power from the electric motor under deceleration. A hydraulic pressure control function balances the total braking force between that supplied by hydraulics and motor. Moreover, whilst remaining well within the vehicle stability threshold, the ECB system favours brake force distribution to the rear wheels whenever possible, in order to both reduce the burden on the hydraulic system and optimise the charging of the Lexus Hybrid Drive system battery.


Hill Start Assist Control

Allied to the new GS 450h's sophisticated ECB system, a Hill Start Assist Control detects vehicle slip during hill starts, automatically increasing brake pressure to all four wheels to provide the driver with ample time to step from brake to accelerator pedal without backward movement of the vehicle.


Intelligent Adaptive Front Lighting (I-AFS)

The new GS 450h also features an Intelligent Adaptive Front Lighting System (I-AFS), which swivels the xenon headlamps through up to 15 degrees, helping to illuminate a bend as the driver steers into it.


Tyre Pressure Warning System (TPWS)

A Tyre Pressure Warning System (TPWS) can detect a loss of pressure in one or more tyres, notifying the driver via a dashboard mounted warning light.



PREVENTIVE SAFETY

Pre-Crash Safety (PCS) system

The new Lexus GS 450h features a sophisticated Pre-Crash Safety system (PCS) that can anticipate a front collision against some types of obstacles and, in addition, help reduce collision damage and injury. The PCS system features a millimetre-wave radar sensor, operating within a wide 20 degree scanning amplitude to detect obstacles in front of the car to a range of 150 metres.

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