[TMS] Nissan Pivo 2: Chassis Transforms to Speed, Slow and Turn

Oct 25, 2007
Motohiko Hamada, Nikkei Automotive Technology
During acceleration
During acceleration
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Nissan Motor Co Ltd proposed the Variable Geometry Chassis (Metamo System) function as a future technology that relates to its concept car, Pivo 2.

At the event site, Pivo 2 does not demonstrate this system, but it is the goal of the development of this concept car to achieve this function. "Right-angle parallel parking" presented in the show is just one example of various movements.

Pivo 2 has wheels provided at the tip of arms extending in four directions from four corners of vehicle body. The car has four rotating shafts for arms and four kingpin shafts for wheels, each of which rotates independently. This structure allows more sophisticated movements than parallel parking.

When the car is accelerated, the front arms are fully extended sideways, and the rear arms are extended rearward. With respect to the tire positions, the vehicle body relatively advances. It is preferable for a 4WD vehicle like Pivo 2 to have a center of gravity in front during acceleration because the load is evenly distributed.

In contrast, when the car decelerates, the front arms extend forward and the rear arms are fully extended sideways, which moves the center of gravity backward to cancel out the effect of load shift caused by deceleration.

When turning to the left, front and rear wheels on the right side are positioned slightly closer to each other whereas those on the left side are rather kept away from each other. Thus, the center of gravity is located at the inner corner, thereby distributing the load, which otherwise tends to be concentrated extremely on the outer wheels, to the inner wheels.

Round actuators and steering actuators are provided on the rotating shafts of arms and kingpin shafts of wheels, respectively, so that each shaft can be controlled separately.

During deceleration
During deceleration
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When making a turn
When making a turn
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