Green cover is a connecting rod of an ellipse mechanism of two pink sliders. A green pinion is fixed to the cover. A grey actuator of yellow rack is fixed to the right slider. Driving force from the actuator is applied to the connecting rod via the pinion rack drive. That ensures smooth motion of the mechanism.
The obtuse angle of violet runway and the mounting actuator on the slider are measures to overcome limited height of the basement. Moving actuator causes some difficulties for connection with hydraulic or electric source.
The mechanism is cut off half for easy understanding.
The car is moved from the basement to the ground floor by a lift (not shown).