Introduction Limited range of motion often incapacitates individuals from living a full life and often requires time and the resources of caretakers to pander to needs to physically handicapped patients. With the maturation of the ‘baby boomer’ generation, there is a sudden onset of the need for specialized care for the geriatrics, but without the labor force to match the demand. With the advancement of technology, new needs can be met. Standard wheelchairs are bereft of motion without able-bodied individuals to operate them, and is not a viable mode of transportation for those who do not have the strength to propel themselves or people to look after them. This leads to many leading secluded, bed ridden lives forgoing meaningful living. Modern
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Since all the mechanisms needed to adhere to pre-set design specifications¬¬, space, functionality, and cost had to be optimized. A scissor lift was chosen for its perceived advantage over other lifting mechanisms, such as linear actuators or pulleys, because of its unique ability to create a large vertical change in height with a relatively small lateral displacement of arm brackets. A pulley was not implemented because of the impractically and safety hazard behind using a complex rope-and-gear driven system to transfer a patient out of bed. Addition safety features would have been needed to protect the user from being caught in the pulley, and catches would have been required to prevent drastic changes in motion in the event the ropes failed. A linear actuator was discounted because affordable devices would not exert the minimum force of 1.4 Newtons required to lift the G.I. Joe action figure; though devices where available on the market that provided more than a sufficient amount of force, their prices exceeded the budgeted $200. In addition, the was a positive correlation between force output of the actuator and size of the actuator itself, making the use of an actuator impractical due to limitation in size of the wheelchair. Though multiple smaller actuators could have theoretically been used to collectively provide enough force, stability, space, and cost were thought to be limiting factors. The issues of slack versus stability associated with scissor lifts rose during early mechanism analysis, but were planned to be addressed by tightening fasteners at the joints and by using a stronger
Since all the mechanisms needed to adhere to pre-set design specifications¬¬, space, functionality, and cost had to be optimized. A scissor lift was chosen for its perceived advantage over other lifting mechanisms, such as linear actuators or pulleys, because of its unique ability to create a large vertical change in height with a relatively small lateral displacement of arm brackets. A pulley was not implemented because of the impractically and safety hazard behind using a complex rope-and-gear driven system to transfer a patient out of bed. Addition safety features would have been needed to protect the user from being caught in the pulley, and catches would have been required to prevent drastic changes in motion in the event the ropes failed. A linear actuator was discounted because affordable devices would not exert the minimum force of 1.4 Newtons required to lift the G.I. Joe action figure; though devices where available on the market that provided more than a sufficient amount of force, their prices exceeded the budgeted $200. In addition, the was a positive correlation between force output of the actuator and size of the actuator itself, making the use of an actuator impractical due to limitation in size of the wheelchair. Though multiple smaller actuators could have theoretically been used to collectively provide enough force, stability, space, and cost were thought to be limiting factors. The issues of slack versus stability associated with scissor lifts rose during early mechanism analysis, but were planned to be addressed by tightening fasteners at the joints and by using a stronger