I spotted this on the Suzuki stand at Geneva. It’s the rear axle of the Vitara, the Hungarian-built Poor Girl’s Evoque.
At first I thought that it was a De Dion axle, on closer examination it turns out to be a torsion beam with driven rear wheels. Possibly other manufacturers have done this before, but it’s the first I’ve encountered. I’d have expected to find a live axle, or a multi-link or double wishbone fully independent system.
If Suzuki deserve credit, then it’s a neat solution. Wheel travel looks limited, given the short trailing arms, but all the virtues of the torsion beam are there – semi-independent operation, a degree of side to side interconnection, and no need for complex and expensive bearings and links. The set up looks cheap to make and easy to install on the assembly line, with the further benefit of easy compatibility with the front wheel drive versions.
De Dion axles are still around, the Smart and Twingo feature them, but they only make sense with a rear mounted engine or transaxle. They’re not really a halfway house to full independence. The axle is still solid, with the rear wheels constantly parallel to each other. The only real advantage is reducing unsprung weight, more so with inboard brakes, as featured on the Rover P6.