The economical and easy method of addressing the problem of stairs for handicap is to design a wheel chair capable of climbing stairs. Stair climbing wheel chair is a modified version of wheel chair that is provided with a mechanism that is helpful for the handicap to climb the stairs with ease.

But even though variety of wheel chair models is available with various adaptations, the one thing in which they are lagging is accessible to all kind of people and complication of their design.

.A simple yet effective climbing mechanism has been analyzed and implemented in designing of stair climbing wheel chair. A detailed description of parts along with working mechanism has been explained below.

· It mainly consists of two larger wheels that may be driven by hand or motor mounted on a shaft attached to the frame of wheel chair.

· A sprocket or a gear with calculated teethes has been mounted on that common shaft, which in turn get driven when the person seated rotates the larger wheel.

· A spider or the triwheel with sprockets or teethed wheels is fixed to the rear end of the wheel chair frame as in fig. which forms a sun and planet gear rotatable about its own axis and along the axis of triwheel, the bottom end of wheel chair consists of two pins at measurable distance mainly serving the purpose of balancing the wheel chair while climbing the stairs.

· A guide arm is fixed to the bottom pin having slots at both ends, the first slot serves the purpose of locking i.e. it provides a limiting angle for tilting of wheel chair whenever person seated pumps the hydraulic hand pump while going from flat ground to climb the stair and balances the wheel chair and its CG, the second slot consists of an another spider wheel with sprockets or toothed wheels which comes in to contact with the ground only during ascending or descending the stairs and remains at rest otherwise.

· A timer belt or chain or frictional belt engages the rear spider and the front spider to the driving sprocket attached to the shaft of larger wheels which, whenever driver wheel gets driven by the operator it drives the smaller wheels through the toothed timer belt and makes the rotation possible.

· For an efficient climbing mechanism a linked spring or a shaft, for robust handling preferably hydraulic mechanism is suggested which can be operated by a hand piston cylinder mechanism placed near the arm rest. Same mechanism has been mirrored on both sides of wheel chair as shown below.

· In case of breaking system ratchet and lever mechanism has been adopted which is fixed to the driving shaft it acts as a locking mechanism.