Visionary Inventor Challenges Orthodoxies In Car Design
The Age
Wednesday January 29, 1997
IS THERE a Rhombus in your future? A visionary Melbourne inventor called Mr Peter Lyell has challenged most existing car design orthodoxies with a design that contains what he believes to be eight world "firsts" and on which he's taken out provisional patents.
The Rhombus - so-called because a rhombus is roughly described as a rounded diamond shape - has single wheels front and rear and two wheels midships. His drawings and models show a car able to carry a driver and three passengers in fully-reclining sleeper chairs with more legroom than in Qantas first-class, huge luggage capacity, greater manoeuvrability than a conventional car occupying the same space, and with greater crash safety.
Mr Lyell has been freelancing as a consultant since resigning seven years ago as group head on the Holden advertising account with agency McCann-Erickson. He has thought a lot about modern car design, and contends it demonstrates its terror of lateral thing, asking: "What in hell have thousands and thousands of engineers being doing since the turn of the century?"
He says futurists like Marshall McLuhan and Alvin Toffler were right. "We keep driving towards tomorrow with the handbrake on, not confronting the demons that might haunt that alien country, but focused instead on the reassuring view of yesterday in the rear vision mirror.
"Despite some progress, this automotive century has been a disgraceful parade of inbreeding and plagiarism, most makers timidly adding variations to a fundamentally flawed format evolving at paralysing pace. Soon there's going to be an apocalyptic London or Los Angeles traffic jam visible from the moon, exacerbated by the car's sheer length, its profligate containment much of the time of a solitary person, and manouevring limitations caused by a turning circle not much better than that of Karl Benz's prototype of 110 years ago."
The world is full of people who believe they can make cars run on water, or improve performance with crystals or have discovered the secret of perpetual motion. Peter Lyell is definitely not a nutter.
In pure engineeering terms, much of his design concept makes considerable sense. He has outlined dozens of distinctive advantages of the Rhombus, which he compares with conventional cars on a wheelbase of 2700 millimetres and weighing 1500 kilograms, but adds, "in so many ways, even the Rhombus is pathetically orthodox".
The power train uses half axles to drive each wheel in the centre of the car, while front and rear wheels do the steering, without any inhibition from the power delivery, thus halving the turning circle for a car of this size to 5.5 metres. About 75 per cent of the braking effort is on the three wheels, front and centre, but because the Rhombus's centre of gravity (CG) is exactly at its own centre, each wheel is sprung, arbitrarily, to support a weight of 375 kg.
Thus braking friction performance and weight transfer can be far more accurately controlled, as can steering reaction. For instance, even if those three wheels locked up under brakes, the rear wheel would still be steering the car.
Peter Lyell has used MacPherson strut suspension for the central wheels but mounted the integral strut/coil on the outside of each wheel inside hollow body centre pillars. Front and rear suspension would be by wishbone and swing-arm mono-shock along motorcycle lines, he says.
The engine lies under the passenger compartment in a sandwich monocoque, as Mercedes-Benz has partly done with the coming new small A-class - certainly a revolutionary car in today's terms. The monocoque would have a sub-floor separated by a honeycomb of bulkheads like a moulded, lidded ice-cube tray that would be immensely strong. At the same time it would allow storage in the compartments for luggage, fuel, spare wheel, battery and similar, thus mounting the heaviest items lowest in the structure.
However, Mr Lyell says that while the CG of the conventional car is about 520 mm above ground, that of the Rhombus would be about 770 mm, close to that of the Range Rover.
The advantage here comes when the car hits a horizontal depression; a normal car will drop perhaps 60 per cent of its weight into it, creating suspension and body mass displacement, whereas the rhombus layout is such that his 70-cm-long scale model with a 1 kg steel block midships representing the power train is still in equilibrium, or balance, with any one of its four wheels hanging over a drop.
The car has so much natural equilibrium it's feasible to dig a hole under one wheel to change it without using a jack. Jacking can use the hydraulic struts on the front and rear wheels powered by the steering pump; there is also so much ability to move passengers and luggage around - like live ballast on a racing yacht - that you could change ride and handling qualities as needed.
The design ensures a much smoother ride, because there is less body mass rebound to control by the dampers, and because the front and rear wheels need far less steering angles, the body doesn't roll as much. The Rhombus would also be much better on rough tracks, particularly those with a high centre "crown", because of the way the centre wheels work.
Peter Lyell's model is conventional two-plus-three seating, but the design allows a central driving position - which sensibly means the same car could be marketed in all countries without the need for re-engineering for left or right-hand drive (the McLaren F1 supercar has this feature). This would also lessen the danger of side impact intrusion to the driver, while the central passengers are protected by the external suspension, central wheels and the massive B-pillar.
There is no central tunnel, so with the completely flat floor there can be three fully reclining armchairs, with fold-down leg-rests. Mr Lyell calculates there would be room for two large suitcases behind and one on each side of the rear passenger, with a total of nine to 11 luggage spaces possible.
"The driver's seat could have integral bins with consoles at each side and would swivel to face either door, so he or she could get out on the safe side in whichever country they were parked."
Mr Lyell says steering wheels and columns are cumbersome, inefficient and dangerous in a collision (other designers have been saying this for years, but a host of tiller and other type designs have been rejected). The Rhombus has twin vertical handgrips on horizontally telescoping joysticks in line with the elbows, so the driver steers by pulling one back and the other forward, allowing control with one hand. "Twin joysticks would also enable the introduction of another world first - thumb-operated brakes, via a pressure bulb atop each steering grip."
His design also includes a single central double-bladed windscreen wiper like an aircraft propellor sweeping 360 degrees once every 0.75 of a second, using centrifugal force to throw water away from the glass.
In a full-on frontal collision, kinetic energy would largely be absorbed by the front wheel, tyre and suspension, along with the progressive crumple rate of the honeycomb structure. There would be no coolant radiator; instead the coolant hose would be routed from the front of the car and back via sub-floor ducts, thus also allowing the removal of the noisy engine-driven cooling fan and lowering the cost of frontal crash repairs.
Peter Lyell admits he hasn't yet had a single car maker talking to him about some of his ideas. But he understands that. Designers and engineers are prisoners of marketers and bean-counters, as well as of buyers who see cars mainly as cheap transport and who are frightened by the unorthodox.
However, he has a simple question. "Why not?"
© 1997 The Age