There is a website called http://www.minardi.it still going strong today. They have just published the following in Italian so we have translated if for you.
Former Minardi and Scuderia Toro Rosso engineer Gabriele Tredozi the ‘father’ of many a car from Faenza explains the origins of the present fashionable FRIC systems.
Firstly, you have to go back twenty years, when active suspension rapidly gained popularity. This technology had the ability to electronically manage the suspension through a number of parameters such as ride height, roll and pitch. All this was no longer done through a conventional spring system, but hydraulically.
The system was composed of actuators placed on the struts. The spring-damper actuators received the oil under pressure through a pump and the electronic controllers handled the front and rear ride height, roll and pitch, thus obtaining a benefit in terms of aerodynamics.
This project can be separated into two parts: a passive part, with the hardware of the hydraulic suspension and active, or electronic.
Martini’s and Fittipaldi’s M193 was equipped with a passive hydraulic system. There was an external pump which pressurised the system, but the car was also equipped with traditional suspension. It worked on the springs controlled by hydraulic lines with the strut that sent the circuit under pressure.
This was the starting point and then we made the system fully active the following year. Unfortunately, the FIA banned the system, so we found ourselves with very advanced, but not exploitable suspension. However, in 1994 we continued to use it without making it active.
The goal was to minimize the variations in height between the front and the rear during braking and acceleration. In order to passively manage pitching of the car, we used cross-connection (link) of the front axle with the rear.
In this way, when the vehicle was under braking, the front actuator created a vacuum in the back, occupied by the oil from the rear, so the rear also crushed to the ground. Doing so kept the height difference unchanged. Cross-connection also helped in the corners.
When the load was greater on the outside rear wheel, intervened on the inside front wheel limiting body roll. The same operation, but the opposite was the case when accelerating and the load is transferred back raising the front. The pressure of the actuators avoided it squeezing the nose to the ground. Doing so decreases the understeer during acceleration.
At the end of 1993, however, the connection was banned. With the M194 then we continued with the hydraulic suspension, but no longer connected. A portion of the benefit was therefore missed. On the other hand, today’s Formula 1 has reappeared this link using a system similar to ours 20 years ago.
TJ13 comment: In that 1993 season there were 16 Grand Prix and between the 2 cars Mindardi have 15 retirements. the following season when the active systems were banned with the same number of races Minardi had 17 retirements.
How we forget….