Designers: Jon Usher, Ankit Jain, Chris Radford
Client Coordinators: Laura Juel, OTR
Supervising Professors: Kevin Caves and Richard Goldberg
INTRODUCTION
Tina is an adult female with facioscapulohumeral muscular dystrophy (FSHD), which is a hereditary, degenerative muscle disease. Tina has balance problems caused by leg weakness and she sometimes falls while alone at home, which is typical for individuals with this condition. The combination of her symptoms makes it difficult for her to get back up independently. Previously, she accomplished this by climbing onto her couch and then sliding into a standing position, which took her between 20 and 60 minutes, and this process was exhausting. Commercial devices available for lifting patients, such as the Hoyer lifts, are expensive and not designed to get a person from the ground to a standing position. We developed a motorized device that lifts our client from a seated position on the ground to a height of 26 ¾ inches. This enables her to slide off of the platform directly to a standing position. She can operate the device independently using a handheld controller. It requires little physical effort, and the entire process takes less than one minute. The device is firmly attached to the wall of her home office.
Figure 1: Photo of the Quicker Picker Upper device
STATEMENT OF IMPACT
Our client, Tina, commented, “This is going to make my life so much easier. The quicker picker upper will greatly impact my life in 2 major positive ways. First and foremost, it will enable me to lift from the floor due to a fall in less than 1 minute. Due to my disability, it may take me up to one hour depending on my strength or tiredness. As a bonus, this creation will enable me to lower myself to the floor and play with my child and will allow me to be more active in the house. I am very grateful for this, thank you again!”
TECHNICAL DESCRIPTION
Our device consists of three components: the frame, the platform, and the lifting assembly, as shown in figure 1. The user slides onto a platform that rests on the ground. A handheld control allows the user to raise the platform to the desired height of about 26 ¾ inches. When the desired height is reached, a limit switch automatically shuts the motor off. The user slides forward off the platform into a standing position. Handles to either side aid the user in dismounting the platform.
The overall size of the frame is 6 feet tall, 35 inches wide, and 22 inches deep. The general shape and size of the device can be seen in Figure 1. Square aluminum tubing was chosen for the frame materials because it has strong mechanical properties, will not deteriorate over time, and has a modern appearance, which will match the other furniture in the home office where it is located. The platform is made of ¾” oak plywood and is 20 inches deep and 33 inches wide. The depth provides space for the user to sit comfortably and the width makes it easy for the user to mount and dismount without interference from the frame. Handles placed near the front of the platform give the user added support when transferring to a standing position.
Figure 2: Operation of the Quicker Picker Upper device
The lifting assembly consists of four cables, guided by a series of pulleys that are attached to the platform on one end and connected to an AC winch on the opposite end. As the motor rotates, the cables wrap around the motor spindle, which shortens the length of the cables and raises the platform. We used a block and tackle pulley configuration, in which each cable wraps around a corresponding pulley, located in each corner of the moving platform. This reduces the force required to move the platform and cuts the speed in half. This gives the user greater control of their location and makes the device more comfortable. Turnbuckles were added in line with each cable to equalize the length of the four cables to ensure that the platform lifts uniformly. We chose an AC electric winch because it is reliable and can utilize the wall outlet in Tina’s office.