Project Number: 06216

ARC OF MONROE COUNTY THERAPEUTICAL POOL LIFT

Kevin Hunter (Mechanical Engineering)

Timothy Martino (Industrial Engineering)

Jeremy Barber (Mechanical Engineering)

Curtis Benedetto (Mechanical Engineering)

Phaelan Vaillancourt (Mechanical Engineering)

ABSTRACT:The current pool lift at the Al Sigl Center does not meet the consumers needs and does not meet ADA/ABA regulations. The purpose of this project was to design, build, and test a pool lift that would be utilized by the Arc of Monroe County. The intent of this project was to create a pool lift that would meet the consumers needs and be user friendly for the staff at the Al Sigl Center, follow ADA/ABA regulations and operate safely without sacrificing the comfort of the consumer. All machining, assembling, and testing were done at the Rochester Institute of Technology by the Senior Design Pool Lift Team. This lift will be installed at the Al Sigl Center once it is deemed a functional prototype and meets standard requirements for approval. For the convenience of the customer; a manual including the installation, maintenance, and troubleshooting will be presented along with the pool lift to address concerns in the future.

INTRODUCTION:The Arc of Monroe County has a therapy pool that many of their consumers use. These consumers have physical limitations, and can not enter the pool by simply walking down the steps and must therefore be lowered into the pool by a pool lift. The current lift is unstable, unreliable, and is not easily accessible. The lift consists of a chair that hangs over the pool with no lateral arm supports. The current pool lift is supported by a small structure and is powered by means of a hydraulic water cylinder that operates on plant water. The hydraulic system is unstable when raising and lowering consumers of all weights in and out of the pool. The weight limitations of the current system are unclear, and any future consumers who are heavier than 300lbs could be in danger if the lift were to fail during mid travel. The Senior Design Pool Lift Team will meet strict deadlines to complete each facet of the project and provide a strong communicational network between group members, advisors and customers.

The main concerns for this project are the safety of the consumer and operator as well as the functionality of the pool lift. The team designed this product to the best of their ability by combining their educational backgrounds along with their CO-OP experiences to provide the best technical approach in order to go above and beyond our customer’s expectations..

NOMENCLATURE:ADA/ABA Regulations: Americans with Disabilities Act/ Architectural Barriers Act.

DESIGN OBJECTIVE/SCOPE:The scope of the project is to improve and replace the pool lift currently utilized by the Arc of Monroe County. The new lift was designed to have a maximum lifting capacity of 400lb. The material used to build the main post, linkage, and seat frame is 6061 Aluminum. The material used for the connection pins were made out of stainless steel; the seat is made of a plastic composite which was purchased from an actual pool lift design in the current market ; and the seat was fully padded with 1/8 inch EVA water resistant foam. The total weight of the new lift was calculated to be approximately 100 lbs. The overall height is 34 in. with a length of 64 in. The new lift will be able to rotate 360 degrees if desired but recommended 180 degrees and have 33 in. of total travel from the raise position to the lower position. The National Science Foundation provided a budget of $1,500.00 for the Senior Design Team to use for this project. The safety of the consumer was emphasized during all practice and was not taken lightly and

played a significant role in the design objective phase of the new lift. BACKGROUND:A. The Arc of Monroe CountyIn 1948, a group of parents formed the Sunshine League, which was an organization to make life better for children with developmental disabilities. In 1956, the Sunshine League became the NYS Association for Retarded Citizens. In 1976, the name of the chapter was changed to more accurately represent the population they serve. In 1993, the name was again changed to The Arc of Monroe County. This change was in response to the request of the agency’s consumers to eliminate the word “retarded.” The ARC of Monroe County, a chapter of NYSARC Inc., is a family-oriented, community organization that focuses on serving the needs of people with developmental disabilities and their families. The ARC welcomes individuals of all ages, backgrounds, and cultures; and provides each person with options through an array of services that facilitate self-determination.

The ARC of Monroe County consists of the following programs: Residential Services, Job Path, Day Treatment, Vocational Services, Diagnostic Evaluation, Transportation, Family Support Services, Guardianship, Service Coordination, Recreation, Day Habilitation, ARC Health Services, and Community Arts Connection. The ARC also operates the following businesses: ARC Floral, Workshops, Deli works, and an Admissions & Agency Information subdivision.

B. Concept Development

This section of the course focused on how the R.I.T. Senior Design Team utilized techniques throughout the course to obtain a final design that fulfilled the requirements of the ARC of Monroe County and consumers. A Quality Function Deployment was done so that the team could identify the most important needs through quantifiable measures and address the concept development process in a more methodical way. A morphological chart was also devised to understand how the pool lift will accomplish the main goal of moving a person from the pool deck into the pool and back over the pool deck safely. After brain storming, concept design sketches were also developed to put our feasibility analysis into perspective. The team eventually set aside a few designs by means of discussing how some of the designs could not be accomplished due to the following: budget, time, and corrosion. Through these considerations and through a feasibility analysis, the group was left with one top design for further development.

C. Budget The National Science Foundation provided a budget of $1,500.00 for this project. Our estimated expenses came out to be a little over $1,300.00 from Senior Design I. The budget played a significant role which would limit the final design. This was a constraint on the project along with the ease to manufacture and time associated with the new Lift. Our power source changed during Senior Design II from a DC winch to a DC linear actuator. Linak and IGUS were vendors who donated both a linear actuator and many bearings for free which enabled

us to further use our budget and have fewer shortcomings on certain features.

D. Vendors/Suppliers Once a final design was selected, the team found out what was needed to meet the design requirements. McMaster was a company where several purchases were made throughout Senior Design II as well as a couple of local suppliers such as Murphy and Nolan which provided lower prices on stock than McMaster. Vendors were used to convey our needs and assess the best products available to be used for this project but within our budget.

E. StakeholdersThe stakeholders are the members of the team and the consumers at the Al Sigl Center. Dr. Debartolo, from the Department of Mechanical Engineering at Rochester Institute of Technology, whom is the advisor and mentor for this project. Kristen Quinlan is a representative from the Al Sigl Center. Kristen is the liaison for the Al Sigl Center and all questions were addressed by her if they had an overall effect on the consumer’s wants or needs. Bill Woodruff is the customer HSE Manager and answered questions regarding both the design and facility where it will be installed.

F. Current Design Figures: 1, 2

The seat hangs over the pool and the hydraulic system is not fully functional. Please note that this lift does not meet ADA regulations. FINAL DESIGN BACKGROUND:A. Preliminary Drawing / ChangesFigure 3: Preliminary Design Drawing

The preliminary design that was presented from Senior Design I changed slightly. The team decided to purchase a pool seat from a vendor, rather than fabricating with different composites. A linear actuator will also be used rather than a DC winch because there is less concern for failure and if the actuator were to fail it would seize in position and there would be no harm to the consumer or operator. There were a few attachment points modified for the linear actuator which will be shown in the CDR PowerPoint.

Figure 4: Purchased Pool Seat

Figures 5 and 6: Linak Linear Actuator

B. Dynamic AnalysisThe new pool lift was designed to operate in a smooth motion for all consumers up to a weight of 300lb. The actual system has been designed to with stand 600lb. The source of power to operate the pool lift is a splash resistant LINAK linear actuator, which is powered by a 24VDC motor. A waterproof control box is attached to the actuator in order to provide a 120AC to 24VDC conversion to enable the operators to control the entire travel of motion for the consumer by simply using a handheld remote. The new pool lift is fully raised when the cylinder is extended, which can be a minimum of 12 inches to 16 based on user preference. Upon being fully extended, the actuator turns off and locks to hold a static load of 1600lbs. This provides the consumer to either be fully raised out of the water or to be rotated by the means of the thrust bearing setup, which enables the operator to safely and easily unload the consumer from the pool edge. When far from the pool edge, the seat has lateral supports that move out of the way to allow the most access for loading. The base is able to rotate 360 degrees but is setup to lock at 180 degrees. The pool lift is also able to lock parallel with the pool when not in use for easy storage, which allows everybody to exit the pool area from either side.C. Structure FEAUsing the finite-element software, ANSYS, finite-element analysis (FEA)

was performed on the critical aspects of the design. To simplify the analysis, each component was modeled, meshed, and solved individually with the necessary boundary conditions applied to each part. There were three main components that were analyzed using FEA:

1) The welded seat support2) Upper and lower linkages3) The main post

Each component was first solved analytically and then compared to the solutions obtained through the FEA. The similarity in results of the two methods provided the team with the confidence needed to affirm the design.

D. FEA ResultsThe upper linkage was modeled in ANSYS as a beam with two pin supports. One pin where the upper linkage connects to the main post, and another pin where the winch cable connects to the upper linkage. The force applied to the free end is 300lbs.

Figure 7: FEA of upper linkage1

MN

MX

X

Y

Z

0

17083417

51256833

854110250

1195813666

15375

FEB 20 200617:50:05

NODAL SOLUTION

STEP=1SUB =1TIME=1SEQV (AVG)DMX =.804473SMX =15375

The bottom seat support (Figure 8), was modeled in ANSYS as a cantilever beam with three vertical forces acting on it. These three vertical forces represent the attachment points the

seat is going to have on the seat support structure. One point at each end of the support as well as in the middle. Since the total vertical force on this beam is 300lbs, each individual force was set to 100lbs

Figure 8: FEA of seat support1

MN

MXX

Y

Z

0

17003400

51006800

850010200

1190013600

15300

FEB 22 200610:55:56

NODAL SOLUTION

STEP=1SUB =1TIME=1SEQV (AVG)DMX =.258965SMX =15300

The post was modeled as a cantilever beam coming out of the ground. Figure 3 only has a moment on the post. This was done to show that ANSYS gave a value close to our hand calculations. Figure 9 shows the main post with all the forces on it. All the reaction forces from the linkages and the force from the load.

Figure 9: FEA of main post

1

MNMX

X

Y

Z

0

897.0351794

26913588

44855382

62797176

8073

FEB 20 200616:35:55

NODAL SOLUTION

SUB =1TIME=1SEQV (AVG)DMX =.232512SMX =8073

SAFETY ANALYSIS:The R.I.T. Senior Design Pool Lift Team focused on the safety of the consumers as the number one priority of this project. The ergonomics of the entire system was designed to limit the amount of human error that can occur during operation of the lift. The final design incorporates ADA requirements and uses certain features to ensure a safe experience during operation. The system is designed to operate in a wet and humid environment. The structure will be coated in a industrial grade paint which can be fully submerged in chlorinated water to prevent corrosion to any part of the pool lift. The rotational base will be water sealed to ensure the systems integrity. A linear actuator replaced the winch setup to provide a means for a smoother transition as well as safer. If the linear actuator fails it will seize in position which will either allow the operators to remove the consumer from the pool or from the pool seat causing no harm to the consumer. This will prevent the consumer from descending into the pool deck or into the pool at a fast rate. The seat is designed to ensure maximum safety and will have a four-point harness so that the consumer will

be fully supported. EVA water resistant foam will also be added to the seat, lateral supports and seat structure for safety of the consumer during loading and transition into the pool. The lateral supports lift out of the way simultaneously during loading to ensure more space when loading and unloading the consumers onto and off of the lift. The actual attachments for the lateral supports are behind the seat and behind the seat frame which ensures no pitch points for the consumer. The lateral supports have also been squared off and rounded so no impalement could occur. The actuator that is being used is splash resistant and the control box is waterproof to ensure the safety of the operator as well as anyone around the pool area. The wiring for the actuator will be ran underneath the pool to a GFCI outlet which will avoid accidents such as tripping over the wires and electric shock from the exposure to the water around the area. All of the edges on the actual structure that could come in contact with the consumer have been rounded for the safety of the consumer and operator. The underside of the pool seat was also taken into consideration and rounded out on the bottom to remove all doubt during loading and ensure a safe transition from in and out of the pool.  The actuator is mounted behind the consumer and all pinch points have been addressed.

MANUFACTURING PROCESS:A. OverviewAfter reviewing all facets of our design and making slight changes, the team devised a schedule to manufacture and build the new pool lift. A pool deck

mock up was first constructed out of 2x4 wood and plywood to simulate an actual pool deck environment. The center of the mock up contains concrete, specifically to add weight and provide extra support to counter act the moment caused when a person is being loaded for this proto type only. In the concrete, there is a stainless steel disc, which was machined to encompass a thrust bearing setup to allow for easier rotation of the main post, which supports all of the structure. An oil impregnated bronze bushing slip fits into a stainless steel disc as well to provide a surface for the main post to rotate upon, which in return decreases friction from transition from over the pool to over the deck. This setup was leveled and then encased in a PVC tube which also acts as a bearing surface and also helps safeguard the parts after all of the concrete is back filled in. This was incorporated for the prototype design only so that the integrity of the base would not be compromised and material would not be wasted but also can be used during installation of the final product. The main post fits securely into the bronze bushing and rests upon the thrust bearing. The main linkage arms which are made of aluminum 6061 were machined and also rounded on the edges for safety. The linkage arms also have a press fit bushing on each side of every hole in the arm to provide a smooth bearing surface during motion of the new pool lift. The main post has stainless steel shafts, which are press fit into the main post. These stainless steel shafts were also drilled so that when the linkage arms are attached with spacers, a coder pin will be utilized to secure the linkage arm onto the shafts, which reside on the main post. A larger lever arm was

machined and attached to the main post to provide a method to rotate the actual lift when in use. The pool seat frame was cut to length per plan and welded together to provide a rigid structure. The back of the pool frame was machined to have attachment points to the four bar linkage system. There are several mounting places for the actual pool seat, which was purchased from a vendor. The bottom of the seat frame was machined to be user friendly and also eliminate any hazard to the consumer and operators. The pool seat itself and arm rest will be padded to provide safety. The actuator will be mounted and tested prior to and after being part of the pool lift system. Originally, the team planned on having the main post rotate inside the bronze bushing but due to the size of the post the machine shop did not have proper equipment to modify the post.  Instead, the team decided to have the main post slip fit into the bronze bushing and have the bronze bushing rotate against the PVC surface for a better bearing surface which decreases friction during rotation.  In reality if the proper equipment were available, the team would have modified the main post but the PVC pipe allows a better bearing surface with less friction.After the complete manufacturing process is complete the pool lift will be assembled to check for fit and function, then disassembled and will be coated with anti-corrosive coats of paint.

B. Machining Pictures

Figures 10 and 11

Aluminum bar stock cut to length

C. Pool deck mock up picturesFigure 12: Plywood deck, concrete filled

Figure 13: Top view of the installation of the thrust bearing setup.

After the completion of the fabrication phase, the lift will be tested on the above base, as mentioned above, by a group member(consumer). This will

allow the Senior Design Team to see if the new design passes inspection and is ready to be installed into the Al Sigl Center for consumers to use.

CONCLUSIONS:The RIT Senior Design Team is in the final steps of building the product. The results of the testing will be elaborated on in the upcoming future. There were no problems that occurred throughout the manufacturing process and the team is 100% confident that the new lift will meet the design requirements to go above and beyond the customers expectations. The ARC of Monroe County will be very please as well as satisfied with their new product. A manual for the lift was made, which consists of installation, maintenance and troubleshooting for all parts used in this project. The actuator manual will also be available for future use. The Senior Design Team designed this lift with safety in mind. This is the most important subject when it comes to the consumers using the product. Every angle of the lift was designed to promote the safety of both the user and operated. A reclining seat was an option wanted by the ARC during the fifth week of Senior Design II. This was discussed with Dr. Debartolo and at this time in point it was deemed that another Senior Design team in the future could provide that as an option. Our team hopes that as future engineers, we can continue to make a difference.

ACKNOWLEDGEMENTS:The team would like to thank Dr. Debartolo for being our mentor and coordinator. Our team would also like to thank Kristen Quinlan for being our point of contact for the ARC of Monroe

County as well Bill Woodruff for providing support and answering questions about the facility. A special thanks to LINAK INC for donating us a linear actuator and controls, and also IGUS INC for all bearings. The team would also like to thank Dave, Rob and Steve in the machine shop for having patience with us and providing all the support we could ask for. A big thanks to the National Science Foundation for funding our budget. This project would not be able to be accomplished with out their support. Disclaimer: This material is based upon work supported by the National Science Foundation under Award No. BES-0527358.

Any opinions, findings, and conclusions or recommendations expressed in this material are those of the author and do not necessarily reflect the views of the National Science Foundation.

REFERENCES:Shigley, Mischke, BudynasMechanical Engineering Design (Seventh Edition). McGraw-Hill, 2004

ANSYS, Inc. ANSYS 9.0Copyright 2004 SAS IP, INC

Parametric Technology CorporationPro Engineer Wild Fire 2.0Copyright 2006 PTC