Portable wheel chair ramp design

Design a portable wheelchair ramp for wheelchair access from the driveway to the house porch. Currently there are few steps there without a ramp. Ramp would go over the stairs and can be easily setup when needed and then removed and stored. Not a permanent installation but ideally it be portable design. Although I am open to starting with a permanent design if faster and easier. Can upgrade it to portable design afterward. Design criteria: • Primarily wood construction. • Ramp consist of two tracks corresponding to the left and right wheels of the wheelchair. • Each track has an inner guardrail spaced to fit between the wheelchairs wheels to prevent the chair from sliding off a track. • Should be able to walk the stairs in the middle between the ramp’s left and right tracks while stepping on stairs and pushing the wheelchair up the tracks. • Ramp angle should not be too steep in order to prevent difficulty pushing the wheelchair, discomfort and hazard. • Maximum weight support 300lbs (chair plus person) Deliverables: Drawing for carpenter Supply list based on inventory at www.homedepot.ca Photos attached showing the stairs, wheelchair and corresponding measurements. Height from driveway level to porch level (step 4) is 29 inches.