A support and guide device capable of smoothly shifting a moving block configured to move along a guide track from one of a plurality of track rails forming the guide track to another of the plurality of track rails even when clearances are secured at joints between the plurality of track rails. Each of the track rails has auxiliary sliding surfaces formed on both end portions of the each of the plurality of track rails in the longitudinal direction, the auxiliary sliding surfaces formed side by side with a guide surface and being inclined with respect to the guide surface. The moving block includes leading sliding portions each configured to face one of the auxiliary sliding surfaces of the track rail when the moving block reaches one of both end portions of the track rail in the longitudinal direction.

A step assembly includes a horizontally extending mounting foot section, a vertically extending head section, a single sloping support member interconnecting the mounting foot section and head section, and a step member having a number of integrally formed horizontal steps extending above and attached to the single sloping support member. The step assembly is narrow in a width dimension for use on a narrow dock section, and the horizontal steps are configured to facilitate personal access to a raised boat on a lift.

Embodiments described herein are directed to a method to determine a speed profile for a stairlift, wherein the stairlift includes a guide device, a carriage, and user interaction device. The carriage is rotatable around a vertical axle by a first drive. A specific mass moment of inertia for a specific person is determined by measuring a correlation between applied torque and resulting rotational acceleration for the first drive or the specific mass moment of inertia for a specific person is determined by measuring the specific persons weight while the specific person is carried on the carriage. An optimal torque is set according to the specific mass moment of inertia. The speed profile is determined applying at the most the optimal torque with the first drive.