Energy-efficient assistive stairs

A method of assisting a user of stairs, comprising the steps of:

• (a) storing energy as a result of the user stepping onto a step platform thereby applying a downward force to the step platform as the user descends the stairs, wherein the step platform is coupled to an energy storage device so that as the step platform moves downwardly in response to the downward force, the energy storage device stores the energy;
• (b) locking the step platform in a position after the user has forced the step platform to a down-most position, wherein locking the step platform comprises moving arms of at least two solenoids disposed on opposite sides of the step platform from a retracted position to an extended position, in which the arms of the at least two solenoids engage the step platform to lock the step platform in the down-most position so as to prevent upward movement of the step platform;
• and
• (c) releasing the stored energy so as to apply an upward force to the user as the user ascends the stairs.

A method of assisting a user of stairs, comprising the steps of:

• (a) storing energy as a result of the user stepping onto a step platform thereby applying a downward force to the step platform as the user descends the stairs, wherein the step platform is coupled to an energy storage device so that as the step platform moves downwardly in response to the downward force, the energy storage device stores the energy;
• (b) locking the step platform in a position after the user has forced the step platform to a down-most position, wherein locking the step platform comprises moving arms of at least two solenoids disposed on opposite sides of the step platform from a retracted position to an extended position, in which the arms of the at least two solenoids engage the step platform to lock the step platform in the down-most position so as to prevent upward movement of the step platform;
• and
• (c) releasing the stored energy so as to apply an upward force to the user as the user ascends the stairs, wherein the step of releasing the stored energy comprises:
• (i) sensing that the user has applied a force to the step platform after the step platform is locked in the down-most position;
• (ii) unlocking the step platform as a result of the user applying the force to the step platform;
• and
• (iii) applying an upward force from the energy storage device to the step platform, so as to apply the upward force to the user, as the step platform moves from the down-most position to an up-most position.