Bath Transfer System

Intro: Bath Transfer System

Abstract

This project is a simple and inexpensive transfer system that  allows a wheelchair user  (or any individual with mobility issues) to easily be transferred from their wheelchair to a bath for bathing purposes with the assistance from another individual (or by themselves, depending on the situation).

Motivation

Before this project was given to us the process of Rosa giving her daughter Vanessa a bath was quite a labor intense process by where she needed to physically lift her into and out of the bath. This did not only put unnecessary strain on Rosa’s back but it was also not a completely safe for Vanessa as well. After getting plenty of input from Rosa which included a picture of a preexisting idea that she liked, we began to come up with ideas that we believe best suited her needs.   

Overall Idea

The system is made of 3 separate pieces:
1) Base
2) Chair
3) Rolling Platform for the chair 

Parts List
Plywood 1/2" thickness
2 to 3 hinges
Aluminum beach chair
Swievl for a boat seat (can be found at a marine store)
4 Caster Wheels (1/2")
3 Gate latch
Stainless Steel U-Bolt, 1/4"-20 X 1" Thread Length, for 1" OD
C-bar (enough length to run the full length of the platform on both sides)
Enough bolts, washers, and nuts to attach all the nessecary parts 

Special Thanks
Quoc Vhin for working on this project for 2 quarters
And other Engineering students for their input

STEP 1: Cutting the Base to Size

The first step in this project is to get the measurements of your bath's width and height (you want the the width of both the inside/outside walls, the width of the overall tub, and also the height of the tub from outside of the tub).  The first base that we used was made of 3/4" plywood that we later would coat with an epoxy resin.  The second version we used a corian material that was donated to us by American Marble 1280 N. Melrose Dr. Vista, CA 92083.

The overall length of the base is equal to the overall width of the tub plus the height of the tub.

The width of the base we used 15".

For the hinging aspect of the base, measure from one end of the base (the height of the tub) then make a cut across.

Use either 2 or 3 hinges to attach the two pieces of the base.

STEP 2: Drilling the Holes for Attachment of C-bar

In this step you will need to drill the holes according to the drawing provides, there are 9X .25dia. through holes on each side of the platform. Then you need to cut out the center hole in the platform for both drainage and weight reduction. 

STEP 3: Cutting the Folding Legs

We used 2 table leg hinges to allow the legs to fold up and down.  We used simple square legs. Since the legs were the same lenght as the floding extyension, we had to coss the legs because they wouldn't fit if we folded it into the platform. 

STEP 4: Modify a Pre-existing Folding Chair

You can use an old or new aluminum folding beach chair.  We used a chair that had a 3 position back for the comfort of our client, but you can use one that fits your needs best.

The only thing that needs to be done to the chair is for the legs to be cut as short as possible, so that it will easily fit onto the platform.
(We used a simple hack saw to make the cuts)

STEP 5: Making Brackets for Latch

The attachment for the chair to the rolling platform will be made by 3 gate latches, these latches can be bought at any local hardware store.  The latches themselves will be attached to the chair, these attachement will be made by bolting the latches to a metal bracket and then U-bolts will mount the brackets to the chair.  The rods will be attached to the rolling platform, 1 and then 2 on the opposing side.

STEP 6: Cutting the Bottom Base of Rolling Platform

The bottom base can either be made out of plywood, corian, aluminum.  However, if it is made out of plywood, then the piece needs to be coated the same as the base piece.  

The bottom base is used to attach the 4 caster wheels and the swivel.

The overall dimension is 14-1/4"W and 16-5/8"H 

STEP 7: The Top Base of the Rolling Platform

The top base can either be made out of plywood, corian, aluminum. However, if it is made out of plywood, then the piece needs to be coated the same as the base piece.

The Overall dimension of the top base is 16.25 inch X 15.00 inch 

STEP 8: Coating Anything That Is Not Water-proof

At this point depending on the types of material that has been used, you may need to coat your material with an epoxy coating (especially if you have used any plywood).

STEP 9: The C-bar Saftey System

You will need 2 peices of C-Bar that spans the full length of the platform. Lay the 2 peices so that you can mark the postions of the holes that you have already drilled on the platform.  As well mark were the cut that needs to be made so that the platform can still fold. when drilling the holes, drill through both the top and bottom of the C-bar. 

STEP 10: Finishing

Most every thing will be attached with bolts and nuts, the size of the bolts should be determined on the hole and thickness of the material that is needed to be attached.  Will all the sharp corners need to be taken care of (filled, sanded, grinded...etc)

See our video on youtube at http://youtu.be/SVhqCPRU6U0

Special Acknowledgements 

Faculty Advisor: Dr. Landsberger 
Cal State Los Angeles Rehabilitation Lab
Quoc Vhin 
Other ME students for the participation  

Rosa and Vanessa Jimenaez for the inspiration behind the project.

Contact Information:  Erich Fischer, [e-mail]  and Prof Sam Landsberger, [e-mail]

Also an youtube video can be viewed at http://www.youtube.com/watch?v=SVhqCPRU6U0

Comments

[kelseymh]

Very nice project! Using the rendering to start, and finishing with the as-built product, is a nice touch.

"Wheelchair bound" is not considered good language -- it is demeaning and reminiscent of the institutional captivity experienced by many disabled people both in the past and today. The term used within the disability community is "wheelchair user." Could you change your text accordingly?

I also have a question about usage. The beach chair seems fairly high off the ground (it's higher than the toilet seat in the Intro (second picture). Is it easy for a wheelchair user with good upper-body strength to transfer themselves into the beach chair?

[ErichFischer]

Thanks for the language change, I had a hard time trying to phrase it but I think your suggestion is a good improvement.

And about your question of whether or not a person with good upper-body strength could transfer themselves into the chair, to tell you the truth I just don't know for sure. I don't see why they couldn't but it has barely been test with the person that it was built for, so I am just not positive.

Thanks for the comment, it was much appreciated

[kelseymh]

It's a really nice design! I think with a Hoyer lift, or maybe even a "trapeze bar" installed, a para could do the transfer themselves, but it's hard to know without having a real user try it out.

I guess from the last step that you're in the Cal State LA ME program? Does the rehab lab there collaborate at all with CSUN? Northridge has a nationally recognized disability program, and it's not like the two campuses are that far apart :-) (I used to drive farther than that for a fancy dinner when I lived in West LA).

[caitlinsdad]

Maybe an L shaped configuration of aluminum tubes or pipes would be better for the wet environment. Have two poles with ball casters that ride inbetween them to act as rails for the transfer movement. Thanks for sharing.

[ErichFischer]

Thanks for the suggestion it sounds like a good idea. We were just under limited supplies for this student project, but it sounds like it would be cool for further improvements to the design.