In each corner of the platform, a linear actuator is fitted to simulate a typical suspension arrangement of a spring and damper.
Working independently or simultaneously, the actuators provide accurate feedback from the track surface from the simulation software enabling the driver to feel every bump, rumble, and surface change.
The actuators can also pitch the whole simulator forwards and backwards to simulate acceleration and braking, as well as side to side for body roll. Able to accelerate up to 1G and replicate frequencies up to 100Hz, the system can simulate any road surfaces, suspension movement, and vehicle vibration to unprecedent accuracy.
On track, accelerations and the sensation of g-forces are transmitted to the driver through the seat. As the largest surface area that the body is in contact with, accurately reproducing these sensations in the simulator is highly important in training and implementing correct car control.
Developed from our military fast-jet simulators for fighter pilots, our g-seat is lined unique pneumatic pressure modules to provide sustained g-cueing. Multiple airbags in the seat and the harness expand and contract to provide localised and sustained pressure, simulating the g-forces felt when cornering, braking and accelerating indefinitely.
This system can be retrofitted into many types of seats, therefore existing simulators can also receive the benefits of Cranfield technology. The low mass of the pneumatic system also means that it can be added to existing weight sensitive motion platforms such as 6-Dof systems without degradation in performance.
The Proportional Rapid Onset (PRO) System allows the seat itself to move independently of the other simulator modules. Situated on an X, Y, Z table, the seat movements can accurately replicate very minor and fast movements that cannot be produced by the main suspension platforms.
For example, under high g-force braking, the driver can be brought closer to the controls and their eye height dropped to simulate the “submarining” effect where the body is compressed. It can also be used to replicate very quick lateral or longitudinal accelerations such as gear changes.
The yaw platform is situated at the base of the simulator and is used to simulate lateral movements of the rear end of the vehicle. This is necessary to feel the limits of traction of the rear tyres, which cannot be achieved by solely depending on the visual system. It is only with a good yaw motion system that a driver can consistently drive right at the edge of the tyre grip limits.
Transitioning from one corner to the next is also felt through this module particularly, for example, driving through high speed chicanes.
TRADITIONAL METHODS OF SIMULATING MOTION (and why we do things differently)
The most common motion solution is the 6-DoF platform, also known as the ‘hexapod’. These systems were originally designed for civil aircraft applications where slow but large movements of pitch, roll and heave are of importance, but very little lateral or longitudinal motion is required.
In motorsport, the exact opposite of this is true. Racecars are very stiff and are designed to minimize pitch and roll. For this reason, excessive roll and/or pitch is sometimes used in simulators to utilise the gravity to add further to the feeling of lateral and longitudinal acceleration. Not only do these systems provide negative cues, it is also physically limited to simulating 1G and requires high-power electronics to move the whole simulator. It can also be a cause of motion sickness to some users as their inner balance is affected.
Additionally, with a traditional motion platform, a period of deceleration is required following an acceleration cue (washout). In order to avoid a miscue and/or reduce motion sickness, the deceleration has to be conducted at a rate that is undetectable by the user. This drastically increases the necessary room required to correctly simulate accelerations associated with high performance vehicles.
A high-speed corner such as the Parabolica at Monza creates around an average of 3g for 6 seconds in an F1 car. Using kinematic equations of motion, it is possible to calculate it would require a staggering 529.74m of travel to generate this in physical lateral movement for the period of acceleration and deceleration required. This feat is only possible with a huge floorspace by moving the simulator on extremely long rails powered by large and expensive motors. The platform would also have to return to the centre position in time to simulate the next corner of the circuit slowly without generating any negative cues for the user.
Our patented g-cueing system is able to get around this by focusing on somatic (tactile) feedback. As humans, we do not actually possess a sense (touch, taste, smell, hear, sight) to “feel” acceleration or g-forces, but instead use a combination of cues to realize we are accelerating. While vision does play a big part, tactile feedback of the forces through the seat and belts enable us to “feel” changes in acceleration in racing. Using our patented technology, we can simulate these sensations to great accuracy and thus deceive the brain into feeling sustained g-forces. This enables us to simulate higher levels of g-forces indefinitely at a higher fidelity, all in a smaller package and footprint.