Abstract: The invention relates to a construction machine for introducing a displacement tube into the ground, wherein the displacement tube comprises a tube base body and, at its lower end, a closure device which comprises at least one closure flap which is adjustable between a closed position, in which the displacement tube is closed downwards by the at least one closure flap, and an open position, in which filling material is discharged from the displacement tube into the ground for forming a filling material column, wherein the construction machine comprises a feed drive for introducing and retracting the displacement tube into and out of the ground, respectively.

Abstract: A scooter with a footboard providing a contact surface for a user of the scooter, with a front axle including a first front wheel and a second front wheel and a rear axle comprising a first rear wheel and a second rear wheel, and with a steering column for steering at least the front wheels. Inclination of the footboard about a roll axis of the footboard effects a steering angle of the two front wheels in a first direction and, at the same time, a steering angle of the two rear wheels in a second direction opposite the first direction. The disclosure further relates to a method for operating such a scooter.

Abstract: A scooter with a footboard providing a contact surface for a user of the scooter, with a front axle including a first front wheel and a second front wheel and a rear axle comprising a first rear wheel and a second rear wheel, and with a steering column for steering at least the front wheels. Inclination of the footboard about a roll axis of the footboard effects a steering angle of the two front wheels in a first direction and, at the same time, a steering angle of the two rear wheels in a second direction opposite the first direction. The disclosure further relates to a method for operating such a scooter.