Final Report All-Terrain Wheelchair For Melody Team #1 Steven Ben Brandon Calavan Ana Groff Sebastian Pineo Dylan Rinker TA: Ms. Sarah Brittain Advisor: Dr. John Enderle Client: Melody Kettle

Client Contact information: David and Patricia Kettle 206 Black Hill Road Plainfield, CT 06374 Phone: (860) 564-6672 (home) Email: [email protected]

Table of Contents Abstract………………………………………………………………...…………………………...……………………………3 1 Introduction………………………………………………………………...………………………………………4 1.1 Background (client and Disability)……………………………………..……………………..4 1.2 Purpose of the Project………………………………………………………………………..……..4 1.3 Previous Work Done by Others……………………………………………………………..…..5 1.3.1 Products………………………………………………………………………………….……5 1.3.2 Patent Search Results……………………………………………………………….…...6 1.4 Map of the Rest of the Report…………………………………………………………………....7 2 Project Design………………………………………………………………………………………………….......7 2.1 Introduction………………………………………………………………………………………..…...7 2.1.1 Alternative Design…………………………………………………………………….…..7 2.1.1.1 Alternative Design 1……………………………………………………...…..7 2.1.1.2 Alternative Design 2……………………………………………………….....9 2.1.1.3 Alternative Design 3……………………...………………………………...11 2.2 Optimal Design………………………………………………………………………………..……..12 2.2.1 Objective……………………………………………………………………………………12 2.2.2 Subunits…………………………………………………………………………………….13 3 Realistic Constraints……………………………………………………………………………………...…..16 3.1 Engineering Standards…………………………………………………………………….…….16 3.2 Economic……………………………..………………………………………………………….…….16 3.3 Environmental…………………………………………...………………………………….………17 3.4 Sustainability…………………………………..…………………………………………….………17 3.5 Manufacturability………………………………………………………………………….………17 3.6 Safety…………………………………………………………...……………………………….………17 3.7 Social…………………………………………………………………………………………….………18 4 Safety Issues…………………………………………………………………………………………...…………18 4.1 Mechanical………………………………………………………………………………….…………18 5 Impact of Engineering Solutions…………………………………………………………………………19 6 Life Long Learning……………………………………………………………………………………………..19 6.1 Social…………………………………………………………………………………………………..…19 6.2 Educational………………………………………………………………………………………..…..20 6.3 Mechanical………………………………………………………………………………………..……20 6.4 Software…………………………………………………………………………………………..…….20 7 Budget…………………………………………………………………………………………………………...….21 8 Team Members Contributions to the Project…………………………………………………...….22 8.1 Brandon Calavan..……………………………………………………………..……………………22 8.2 Ana Groff….……………………………………………………………………………………..……..22 8.3 Steve Benn……………………………………………………………………………………..………23 8.4 Sebastian Pineo……………………………………………………………………………..……….23 8.5 Dylan Rinker..…………………………………………………………………..…………………….23 9 Conclusion…………………………………………………………………………………………………………23 10 References……………………………………………………………………………………………………...….23 11 Acknowledgments…………………………………………………………………………………………..….24 12 Appendix………………………………………………………………………………………………...…………24 12.1 Updated specifications………………………..………………………………………….....……24 12.2 Purchase Requisitions and Price Quotes…………………………………...…………..…25

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Abstract The purpose of this project is to design and develop a multi-purpose, allterrain wheelchair for Melody Kettle. Melody is a 21 year-old girl who suffered a detrimental brain injury as a child. The devastating brain injury left Melody not only intellectually and developmentally disabled, but also 100% dependent upon others for her care. She is unable to walk and requires wheelchair assistance for her daily life. At present, Melody does have a wheelchair; however it is fraught with limitations. As such, Melody and her family are in desperate need of a new, modern wheelchair that is customized for Melody’s physical, emotional, medical and therapeutic needs. Because of her current wheelchair’s limited maneuverability when going off-road, Melody rarely goes outdoors. As Melody appears to thrive outdoors, she needs a wheelchair with off-road capabilities. This chair will have the ability to traverse all types of terrain and will be easily operated by any of Melody’s caretakers. Melody is now 21 years-old and is not as easy to lift as she was in the past. Therefore, the new wheelchair needs to be a lighter-weight design than her present one. The wheelchair will be customized for Melody’s height, weight and physical limitations (i.e. past spinal surgery significantly limits Melody’s neck and head movement). It will also have additional customized components such as: vibration, visual stimulation and storage space for Melody’s medical necessities. The chair will provide happiness for Melody and a sense of relief for Melody’s caretakers as it will be equip with everything she may need in case of a medical emergency. While structure and function are of the utmost importance in this project, the true goal is to provide Melody and her family with a significantly improved quality of life. The projected budget for this project is about $1,105 for our team. A timeline of tasks to be carried out was created in order to efficiently complete the project in steps. Each of the team members was assigned various tasks to aid in the completion of the project.

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1 Introduction 1.1 Background (Client and Disability) Melody’s anoxic brain injury was the result of a prolonged seizure. According to Melody’s parents, the seizure was likely caused by an immunization reaction. Before the seizure, Melody was a happy, healthy 18-month old little girl who was developmentally and intellectually on target for her age. This life-altering anoxic injury has left Melody severely disabled; both mentally and physically. She is completely dependent on others for 24-hour care. She receives nursing care 11 hours per day and relies on her immediate family members for the remainder of her daily care. She cannot do any of her activities of daily living. She can breathe on her own, though she has intermittent oxygen requirements and must have an oxygen tank available to her at all times. She cannot feed herself and has difficulty with the mechanical act of swallowing. Her swallowing is also affected by the copious amount of respiratory secretions that she produces. She requires frequent suctioning by her family and nursing staff. She has a surgical feeding tube to provide her nutritional support. Melody has minimal interaction with her family and environment. Melody cannot speak and has severely impaired vision. Melody will smile and utter some happy, though unintelligible, sounds when she is positively stimulated. Melody’s doctors believe she is clinically blind, though to her family, she does appear to react to certain visual stimuli. Either way, her vision is severely impaired. Melody has also endured multiple surgeries in the past. She underwent spinal instrumentation (with metal rods) and fusion that has left her with significantly limited range of motion in both her head and neck. Despite her severe disabilities, Melody does appear to have some voluntary control of her head. She is currently able to activate a head switch, in the temporal regions of her head that can turn on and off some mechanical devices that provide vibratory stimulation. Not surprisingly, Melody’s physical, mental and intellectual disabilities require a great deal of need. Because Melody has minimal interaction with her environment, when she does respond positively (by smiling and uttering happy sounds), her parents are overjoyed. They want to provide her with as much positive stimulation as possible to improve her quality of life. She loves being outdoors, especially in the family’s large backyard. Melody’s father, David, specifically asked us if we could design a wheelchair with off-road capabilities for Melody.

1.2 Purpose of the Project The goal of this project is to improve Melody’s quality of life. Melody is completely wheelchair dependent. Her wheelchair is her current lifeline, though at present, it has significant limitations. It is only suitable for indoor use and Melody thrives when outside. On the limited occasions when Melody is able to go outside, the only person able to maneuver Melody and her current wheelchair is David. He is the only family member that is physically strong enough to lift Melody while simultaneously manipulating the heavy wheelchair.

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Melody also responds to some visual and vibratory stimuli. She smiles and makes happy sounds when she sees certain objects and feels vibrations (similar to a massage chair). As Melody’s family has witnessed her joy from being outdoors and from certain visual and vibratory stimuli, it is imperative that all of these components be incorporated into this project. Melody’s medical necessities will also be addressed in the wheelchair. The chair will be complete with an emergency kit, oxygen and suction; all of which Melody needs to breathe comfortably. Last, a feature to protect her from the outside elements will be implemented as a covering or shade that will shield her from the sun and wind for example.

1.3 Previous Work Done by Others 1.3.1 Products In the last decade the need for all-terrain wheelchairs has skyrocketed. The exact reason as to why the need has grown is not completely known, though one suspects it may have to do with the larger number of military personnel who are living with significant physical disabilities. We are a society at war, and have been for a significant number of years, and we have many young wounded soldiers that have disabilities that require wheelchair use. These young men and women do not want to be locked indoors. They want to be back on the road doing all of the things they used to do. Therefore, if our soldiers are going to be wheelchair-bound, the wheelchairs best have the most innovative all-terrain capabilities. The same is true for all people of disabilities requiring wheelchair use. They all should have the opportunity to have the most technologically advanced devices that can return them to a life filled with opportunity, both indoors and outdoors. To meet this demand, there are a lot of companies that have started to design and produce a number of allterrain wheel chairs; both manual and electric. These chairs can travel the beach, the hiking trails or even the average back yard. They provide their recipients with the freedom to explore a myriad of environments. The Hippocampe, pictured in Fig. 1, manufactured in the United Kingdom, is an example of an all-terrain wheelchair in use today [1]. The Hippocampe design incorporates an extra-large, double width, rear wheel that allows it to easily maneuver in mud, sand, snow and most extreme off-road conditions. It is designed with a low seat so that the user can get in and out of the chair with ease. The chair is also relatively light, so much so that it floats in water. All of the parts on the wheelchair are water and sand resistant and have protected (sleeved) aluminum tubes that keep them from getting hot in the sun.

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Figure 1. Hippocampe Scooter Additionally, there is a current wheelchair attachment, the LOMO 360 (Fig. 2) that is designed for off-road use. Manufactured by Stricker Hand Bikes in RehaEntwicklungen, Germany, this tubular framed attachment with an all-terrain wheel increases the users’ mobility when attached to a wheelchair [2]. It allows the user to traverse obstacles and move off road with ease. The LOMO 360 is adjustable so that it can fit many styles of chairs. It attaches to the wheelchair by two clamps that are intricately designed so no damage is done to the wheelchair when attached. It is also designed to lift the front casters of the chair of the ground, thereby allowing the third wheel top pivot and maneuver with ease.

Figure 2. Stricker Hand Bike Lomo 360

1.3.2 Patent Search Results A search on relatively recent, wheelchair based United States patents revealed the names of two gentlemen, John W. Rackley and Stuart G. Oxford [3]. On October 29, 2008, John Rackley, filled a patent (US Patent 7900945) for an all-terrain wheelchair with independently operating right and left push bars. This wheelchair allows the user to move forward, by pushing the bars forward, or backward, by pulling the bars back. In order to turn, the user must push one bar forward and pull another bar back. The chair was designed so that the operator can shift into different gear ratios depending on the terrain: snow, mud or sand. This provides the user with a significant deal of freedom. Many years prior to Rackley’s patent, on October 9, 1990, Stuart G. Oxford filed a patent (US Patent 75149118) for an all-terrain wheelchair [4]. The wheelchair

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frame is constructed from tubular, air filled members that allow the chair to float. The wheelchair is designed so that it can be used in water (as it floats due to the air filled tubular pieces) or on land. Additionally, two rear drive wheels (controlled by ratchet arms) are mounted on the rear portion of the wheelchair while a front wheel is mounted on the forward end of the wheelchair. This allows for all-terrain maneuvering. Additional measures can be made for further flotation, such as securing a paddle wheel to the rear wheels (to provide propulsion in the water) or adding additional flotation tanks.

1.4

Map of the Rest of the Report

The remainder of this report will provide a detailed account of the optimal design of Melody Kettle’s new all-terrain wheelchair. It will describe each subunit of the wheelchair in detail. Three alternative designs for the wheelchair will also be discussed. The report will also include a discussion of: the budget for the project, safety modifications, realistic constraints, impact of engineering solutions and lifelong learning experiences for each team member. Each team member will also outline the work that he or she completed for the project. The end result will be a thoroughly detailed optimal design.

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Project Design

2.1

Introduction

In the following sections, we will describe the planning and brainstorming involved in the optimal design for Melody’s all terrain wheelchair. For Melody’s wheelchair, we came up with three different alternative designs, each with their own unique features. Following the alternative designs, each individual optimal design subunits are described in detail.

2.1.1 Alternative Designs 2.1.1.1 Alternative Design 1 For the design of the all terrain manual wheelchair, we will be using a threewheel design similar to the Hippocampe (as seen below in Fig. 3) [1]. We will be constructing a new metal frame from stock tubing. Once the frame is constructed, we will use one of Melody’s older wheelchairs (that was donated to us by the Kettle family) and adapt it to fit the new metal frame. Using the older wheelchair is extremely beneficial in this alternative design as the chair is already built to perfectly fit Melody’s body and it has a built-in lever-assisted recline function. The reclining function is hugely beneficial to Melody’s caregivers when they are repositioning her. It allows them to move her without having to lift her; thus giving some of Melody’s smaller-bodied caregivers the ability to aid in her assistance. Using Melody’s prior wheelchair is also a great budgetary savings for this project.

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Figure 3. Hippocampe To make sure the wheelchair is capable for off-road use, we will be using a total of three wheels in the design. The two rear wheels will be large and similar in construction to mountain bike tires. These wheels will be detachable, making it much easier for Melody’s family to store her wheelchair at home and when they travel. There will only be one wheel in the front of the chair, and this wheel will be smaller than that of the two rear wheels. The front wheel will be smooth and will have the ability to rotate 360-degrees. Having 360-degree rotation provides ease of maneuverability when traversing rough terrain. Melody’s family will have the ability to take her on all different types of surfaces; thus allowing more freedom. As Melody will now have the ability to travel on all different kinds of surfaces, the chair will be equipped with rear shocks so that Melody’s body is not affected by uneven or unfavorable terrain. The rear shocks will help to absorb the impact forces that Melody may encounter while off-road. Since Melody cannot control the chair at all by herself, her family needs to have complete control over the chair at all times. As such, the chair will be equipped with disc brakes; similar to those in place on a mountain bike. The brakes will be placed on the inside of each of the rear wheels. They will be well out of Melody’s reach, alleviating any worry that Melody could have her hands stuck within the braking system. Melody has undergone extensive spinal surgery with metal instrumentation and fusion. Her spinal mobility has since been extensively limited. Because of her limited mobility, likely scar tissue build up and subsequent discomfort, Melody needs a custom-built seat that fits the exact contour of her surgically altered spine. The seat must also be cushioned extensively to avoid any pressure ulcerations that could occur on Melody’s skin. We would prefer to have a new seat created that is cushioned and customized to Melody’s spine. If we can get a seat donated by the company that created Melody’s current seat, we will do so. If that is impossible, we will use Melody’s current seat and adapt it to fit in the wheelchair we are creating. When we adapt it, we will ensure it can be secured into this chair and be easily removed (to be placed back into her current chair whenever they wish to use it). The new wheelchair will be also be equipped with special features that are necessary for Melody’s medical condition. The chair will have a safety harness that will securely keep Melody fixed to the chair when she is travelling on rough terrain. This will be a 5-point harness, similar to those designed on an infant car-seat. Since Melody has no control of her own body, she definitely needs a safety harness available to her. Her family can decide whether or not to use it (i.e., when she is just at rest or indoors). Additionally, Melody needs to have oxygen available to her at all 8

times. She suffers from constant sputum production and can easily choke on her own secretions. Oxygen therapy prevents any further anoxic damage occurring to her body. The wheelchair will have space to store an oxygen cylinder and a functioning suction canister (to remove some of the copious amount of secretions that Melody produces). Melody’s chair will also have room for her emergency medical kit, or “go-bag” as Melody’s family refers to it, that is complete with her medical history, medications and family contact information. The chair will be designed with a retractable cover that can be pulled over Melody’s head and body in poor weather conditions. In ideal weather conditions, the cover will be pulled back and stored behind Melody. Lastly, since Melody seems to thrive (she smiles, coos and makes happy noises) when her body is affected by vibrating stimuli, we will also be incorporating a vibration component into the chair. Melody’s chair will vibrate whenever she hits a particular button with her head. Her parents will also have the ability to override the vibrating component so that if they feel Melody does not need to be vibrating in her chair, they can simply turn the function off.

2.1.1.2 Alternative Design 2 This second design for Melody is also a three-wheeled, manual wheelchair. This chair differs from that explained in Alternative Design 1 in that its frame is not newly constructed. We will be utilizing the chair that Melody’s parents have donated to us for use in this project. Using a donated wheelchair saves an incredible amount of money in this project. The donated chair is not the one she currently uses, it is one she has used in the past and her family has kept it simply for spare parts. While the chair still has three wheels, the wheels are positioned completely different than that in Design 1. There will be two large wheels in the front of the chair (and the tires will again be similar to mountain bike tires) and one mediumsized wheel in the rear of the chair. The rear wheel will be smooth and have the ability to rotate 360-degrees. Having 360-degree rotation provides ease of maneuverability when traversing rough terrain. Melody’s family will have the ability to take her on all different types of surfaces; thus allowing more freedom. This chair will be extremely similar in design to Francisco Lupin’s “All Mountain Wheel Chair” (seen below in Fig. 4) [6]. Again, so as to save space and provide ease during travel, the two front wheels will be removable whenever desired.

Figure 4. All Mountain Wheelchair 9

Since a base frame is not being built in this design, we will have limited space for extra features. We will need to make the most of the space available to us. We will use a drum braking system (that does not take up much space) and place a brake into the hub of each of the large front wheels. The brakes will be controlled by Melody’s parents (as she cannot control her own movements). This type of braking system is seen on some types of mountain bikes. Since this design only has on rear wheel, we will only be using one rear shock so as to again limit some of the impact forces that Melody may encounter when she is traversing rough terrain. Melody has undergone extensive spinal surgery with metal instrumentation and fusion. Her spinal mobility has since been extensively limited. Because of her limited mobility, likely scar tissue build up and subsequent discomfort, Melody needs a custom-built seat that fits the exact contour of her surgically altered spine. The seat must also be cushioned extensively to avoid any pressure ulcerations that could occur on Melody’s skin. We would prefer to have a new seat created that is cushioned and customized to Melody’s spine. If we can get a seat donated by the company that created Melody’s current seat, we will do so. If that is impossible, we will use Melody’s current seat and adapt it to fit in the wheelchair we are creating. When we adapt it, we will ensure it can be secured into this chair and be easily removed (to be placed back into her current chair whenever they wish to use it). The new wheelchair will be also be equipped with special features that are necessary for Melody’s medical condition. The chair will have a safety harness that will securely keep Melody fixed to the chair when she is travelling on rough terrain. This will be a 5-point harness, similar to those designed on an infant car-seat. Since Melody has no control of her own body, she definitely needs a safety harness available to her. Her family can decide whether or not to use it (i.e, when she is just at rest or indoors). Additionally, Melody needs to have oxygen available to her at all times. She suffers from constant sputum production and can easily choke on her own secretions. Oxygen therapy prevents any further anoxic damage occurring to her body. The wheelchair will have space to store an oxygen cylinder and a functioning suction canister (to remove some of the copious amount of secretions that Melody produces). Melody’s chair will also have room for her emergency medical kit, or “go-bag” as Melody’s family refers to it, that is complete with her medical history, medications and family contact information. The chair will be designed with a retractable cover that can be pulled over Melody’s head and body in poor weather conditions. In ideal weather conditions, the cover will be pulled back and stored behind Melody. Lastly, since Melody seems to thrive (she smiles, coos and makes happy noises) when her body is affected by vibrating stimuli, we will also be incorporating a vibration component into the chair. Melody’s chair will vibrate whenever she hits a particular button with her head. Her parents will also have the ability to override the vibrating component so that if they feel Melody does not need to be vibrating in her chair, they can simply turn the function off.

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2.1.1.3 Alternative Design 3 For the third design, we will construct an adapter that will attach to the front of Melody’s existing wheelchair; similar to the Lomo 360 by “Stricker” (seen in Figure 3 below) [2]. The adapter will have two mechanical arms that will attach to the wheelchair and a front fork that holds a medium-sized mountain bike tire. Melody’s current wheelchair presently has two small wheels in the rear. Since the small wheels do not presently accommodate off-road use, we will provide two large, off-road (mountain-bike like) wheels that can be easily exchanged when wanting to use the adapter. When attached to the chair, the adapter will raise the front caster off of the ground; allowing for greater ground clearance. The single wheel in the front of the adapter will have the ability to rotate 360-degrees; providing ease of maneuverability when traversing rough terrain. Melody’s family will have the ability to take her on all different types of surfaces; thus allowing more freedom.

Figure 5. Lomo 360 Since this design consists of a device that acts as an accessory to Melody’s current wheelchair, we will not have to acquire a new seat or purchase a safety harness. We can use the seat and harness in her current chair. However, Melody’s has extensive medical needs and must have certain items available to her at all times. She suffers from constant sputum production and can easily choke on her own secretions. Her adapter for her wheelchair will have space to store an oxygen cylinder and a functioning suction canister (to remove some of the copious amount of secretions that Melody produces). The adapter will also have room for her emergency medical kit, or “go-bag” as Melody’s family refers to it, that is complete with her medical history, medications and family contact information. We will design a retractable cover for her current chair that can be pulled over Melody’s head and body in poor weather conditions. In ideal weather conditions, the cover will be pulled back and stored behind Melody. Lastly, since Melody seems to thrive (she smiles, coos and makes happy noises) when her body is affected by vibrating stimuli, we will also be incorporating a vibration component into the chair. We will add a vibratory component to Melody’s current chair. The chair will vibrate whenever she hits a particular button with her head. Her parents will also have the ability to override the vibrating component so that if they feel Melody does not need to be vibrating in her chair, they can simply turn the function off.

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2.2 Optimal Design 2.2.1 Objective This chair will have the ability to traverse all types of terrain and will be easily operated by any of Melody’s caretakers. Melody is now 21-years-old and is not as easy to lift as she was in the past. Therefore, the new wheelchair needs to be a lighter-weight design than her present one. The wheelchair will be customized for Melody’s height, weight and physical limitations (i.e. past spinal surgery significantly limits Melody’s neck and head movement). It will also have additional customized components such as: vibration, visual stimulation and storage space for Melody’s medical necessities. The chair will provide happiness for Melody and a sense of relief for Melody’s caretakers as it will be equipped with everything she may need in case of a medical emergency. While structure and function are of the utmost importance in this project, the true goal is to provide Melody and her family with a significantly improved quality of life. The wheelchair will be designed so that it will be easily maneuvered off-road. The tires will be suitable for off-road use on all different types of terrain. The chair will incorporate a larger rear wheelbase with a single front wheel. The larger wheelbase will allow for more stability where the single front wheel will allow for greater maneuverability in all types of terrain. It must also be lightweight and easily maneuverable. To accomplish the design, we will be building a three-wheeled wheelchair with a lightweight frame. The frame is going to be built out of a lightweight material such as aluminum or steel. When constructing the frame, we will be using round tubing. This ensures that there will be no square corners in the design that Melody could injure herself on. Because the typical wheelchair wheel is very narrow for ease of pushing on hard surfaces, they will not be used. A narrow wheel is just not suitable for off-road use. To solve this issue, we will be using wider, knobbier tires. The rear tires will be a large diamter. For ease of maneuverability, the front tire will smaller and narrower than the front. To ensure that the wheelchair glides across unstable terrain, we will be equipping the rear wheels with shocks. The wheelchair must have the ability to stop instantaneously. In order to achieve this, a disc braking system will be used. The brake system will be mounted to each side of the axle and controlled by a hand lever located on one handle of the wheelchair. There will also be a hand break and a parking brake system (a bar that rotates on the axle, so when stopped, the wheels can be locked into place) for additional stopping and locking measures. Melody’s chair will also need a customized seat that reclines backwards, allowing her Melody to be suctioned easily. This seat also allows for Melody to be repositioned easily. Repositioning is key to preventing pressure ulcerations from developing on Melody’s body. Melody’s chair will also be designed with both cushioned headrests and armrests. Since Melody does not have any functional control of her body, her head and extremities need to be protected by cushioning in case she involuntarily flails them around. To make sure her correct measurements are used, we will be using an older wheelchair of Melody’s that her family has given us. The older chair was built to

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Melody’s exact measurements (and they have not changed since this chair was used) we can use this as a model for the design. Her customized specifications will be built into the frame design of the new chair. Melody also needs to be able to go outside year round in any weather condition. Therefore, it is imperative that a retractable cover be mounted to the chair. The wheelchair also needs to be extremely safe, and must not compromise Melody’s health, comfort, posture or range of motion. There must be space for oxygen and suction canisters because without these items, Melody could suffer from rapid respiratory distress. Melody is suctioned continuously due to her copious amount of respiratory secretions and must have suction available to her at all times. There must also be enough room for Melody’s “go bag.” This “go bag” is what Melody’s family refers to her emergency medical kit. It contains first aid supplies along with a list of contact telephone numbers, Melody’s past medical history and current medication list. In the event that Melody needs to be transported to the hospital by someone other than her family member, medical staff can obtain all of her pertinent medical information from her “go bag.”

2.2.2 Subunits Like any finished product, this all-terrain wheelchair will be the sum of its parts. This all-terrain wheelchair will be comprised of multiple smaller subunits. All of the subunits together will create the completed wheelchair. It is imperative that each subunit is designed not only to serve an individual function, but it must also integrate smoothly within the overall wheelchair design. This section describes each of the subunits individually, making mention as to where each subunit fits into the overall design. Main Frame The frame of the wheelchair will be built composed of 6061-T6 2x2-inch square tube stock aluminum. This is a high-strength aluminum alloy that can be manipulated by welding. The aluminum can be welded very easily and unlike some metals, a welded area will be just as strong as un-welded aluminum after a few weeks have elapsed. The frame will be assembled and welded (wherever necessary) almost immediately so that the welded areas of aluminum can recover and regain their maximum strength before Melody uses the wheelchair. Chair Frame The Kettle family is donating one of Melody’s previously used wheelchairs that was built exactly to her body’s specifications. This chair will be used as the chair frame for this project. The wheelchair frame contains a positioning system within it that is comprised of a harness and safety belt. This system is designed to keep Melody within the center of the chair so that she may safely ride on different types of terrain. This positioning system is adjustable as Melody grows. Wheels (Front and Back) The wheels of this all-terrain wheelchair must be large, wide and have enough tread to traverse through all different types of terrain. We would like Melody’s chair to be able to travel through sand, dirt, snow and mud. Having wheels

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of differing size and composition will allow for most efficient all-terrain use. The two rear wheels will be approximately 24 to 29 inches in diameter and will be composed of material similar to that of a mountain bike (Fig. 6). The front wheels will be approximately 10 to 14 inches in diameter and will be similar to those used on a stroller or trailer wheel. In order to effectively travel on different terrain, all of the wheels must be able to function at different air pressures.

Figure 6. Mountain bike wheels Brakes

Melody’s anoxic brain injury does not allow her any functional use of her arms or legs. She does not have the ability to move or stop her wheelchair. As such, her parents and caregivers must have the ability to stop her all-terrain wheelchair instantaneously and at any given time. As such, the wheelchair will be equipped with a disc braking system. The brake system will be mounted to each side of the axle and controlled by a hand lever located on one handle of the wheelchair. There will also be a hand break and a parking brake system (a bar that rotates on the axle, so when stopped, the wheels can be locked into place) for additional stopping and locking measures. The brake system used will be similar to the Nashbar Mechanical Disc Brake Set, below in Fig. 7 [7].

Figure 7. Nashbar mechanical disc brake set Shocks

This all-terrain wheelchair is being designed so that it effectively travels through all different types of terrain. However, it must travel the terrain smoothly and comfortably without causing any distress to Melody when she rides. Therefore, the wheelchair will be equipped with the Fox shocks seen in Fig. 8 below [8]. The force the wheelchair experiences as it goes over rough terrain must be damped. Shocks, or large springs in this case, function as dampening devices. These springs must resist the mass of the wheelchair plus the force of additional shock from 14

uneven terrain. The springs will provide Melody with an underdamped response from rough terrain. As a result, Melody’s body will not feel the impact of any uneven or difficult terrain. Without shocks, Melody would experience an overdamped suspension response to bumps or rough terrain and she would be unnecessarily jostled. The goal is to provide Melody with a smooth ride no matter the type of ground traveled.

Figure 8. Shocks Seat Melody’s wheelchair seat must be customized and cushioned so that it provides Melody with maximum support. The chair will have the ability to recline backwards so that Melody can be orally or nasally suctioned whenever her secretions accumulate. While it is ideal to keep Melody centered within the chair, Melody must be able to be repositioned easily as repositioning is key to preventing pressure ulcerations from developing on Melody’s body. Safety Harness Most wheelchairs designed for individuals with disabilities are equipped with safety harnesses that provide stability, security and support for the disabled individual [9]. Melody’s anoxic brain injury inhibits her ability to sit up straight and control her motor functions. Therefore, Melody must be safely secured within her chair at all times and safety straps will be incorporated into our wheelchair design. The safety harness will be a butterfly strap padded harness (similar to the Healthwares Flexible Chest Harness seen below in Fig. 9), which will help to keep Melody’s body straight against the back of the seat [10]. The Healthwares Flexible Chest Harness can be worn on all individuals, though it is particularly suited for women (as compared to a traditional H-strap harness) due to the location of the buckles. The harness will wrap around Melody’s shoulders and clip together on either side. The harness closely resembles those used as baby carriers or backpacks.

Figure 9. Healthwares Flexible Chest Harness 15

Miscellaneous Features The wheelchair must have space for oxygen and suction canisters because without these items, Melody could suffer from rapid respiratory distress. Melody is suctioned continuously due to her copious amount of respiratory secretions and must have suction and oxygen available to her at all times. There must also be enough room for Melody’s “go bag.” This “go bag” is what Melody’s family refers to her emergency medical kit. It contains first aid supplies along with a list of contact telephone numbers, Melody’s past medical history and current medication list. In the event that Melody needs to be transported to the hospital by someone other than her family member, medical staff can obtain all of her pertinent medical information from her “go bag.”

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Realistic Constraints

The biggest constraint we are faced with in the design of this wheelchair is Melody’s medical condition itself. The purpose of this project is to provide Melody with an all-terrain wheelchair that will improve Melody’s quality of life. However, Melody’s medical condition and all of its complications must not be compromised in any way.

3.1

Engineering Standards

This all-terrain wheelchair will be designed to meet industrial wheelchair development standards. It will be composed of high quality material and will be best suited for all of Melody’s medical conditions. It will maintain function similar to that of most wheelchairs and almost identical to all-terrain wheelchairs. All members of the design team will undergo machine shop training (including safety training) so that the wheelchair can be optimally fabricated. We will ensure optimal craftsmanship while all parts are made and when the wheelchair is assembled.

3.2

Economic

Wheelchairs are expensive and customized wheelchairs for disabled individuals are even more costly. The average cost of a wheelchair is close to $7,000 (disabled-world.com) though, wheelchairs in general can cost anywhere between $3,000 and $30,000 (disabled-world.com). Not surprisingly, economic constraints are a major concern for this project. We suspect that the majority of the costs for this project will be related to the special needs of Melody’s medical conditions. The materials that comprise the wheelchair (tires, frame, seat, brakes, etc) are expensive to obtain and customize. We do have a set budget for the project, though we are concerned as to how we can meet all of Melody’s needs while we stick to the budget. As such, we are going to seek donations from many different companies so that we can create the highest quality all-terrain wheelchair that will meet all of Melody’s healthcare demands.

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3.3

Environmental

Manual wheelchairs have minimal impact on the environment. It is imperative that Melody’s wheelchair does not destroy any of the types of terrain it is designed to travel through. The tires will be similar to mountain bike tires that are readily used without any damage to the environment. We also plan on using materials (aluminum frame, tires, etc) that will not damage or negatively impact the environment. We are concerned that extreme environmental conditions, like rain, sleet and snow, could potentially damage the wheelchair over time. Therefore, we will recommend that the chair be stored indoors. We certainly expect the wheelchair to operate in all types of weather conditions and it will be designed to do so. However, extensive exposure to harsh elements could damage the strongest of materials. Therefore, we will recommend that the wheelchair be stored indoors when not in use.

3.4

Sustainability

It is imperative that this wheelchair be sustainable for a long time. Melody’s family has limited resources available to them and must make use of the materials they have. They simply do not have the financial ability to buy Melody a new wheelchair whenever they wish. This wheelchair will be designed so that it can be used for many years with minimal maintenance. It will also be able to be adjusted for Melody’s changing body as she grows. Since all materials wear and tear over time, we will make sure the wheelchair parts can be easily replaced if necessary. We want to do whatever is necessary to limit costs and maintenance of the wheelchair for the Kettle family. We will recommend that the chair be cleaned regularly (to remove dirt, water, nature components, etc) to prevent corrosion and damage to the wheelchair.

3.5

Manufacturability

We suspect that this wheelchair, with all of its customized specifications, will be somewhat difficult and expensive to create. However, after building this wheelchair for Melody, we hope to be able to learn a great deal as to how manufacture future wheelchairs at less cost. We can order products in bulk to cut down on costs and we can use any and all donated materials to further decrease prices. Additionally, we can select material that is durable and easily manufactured.

3.6

Safety

Melody’s all-terrain wheelchair must be functional and extremely safe. Her wheelchair will be equipped with a safety harness that will provide Melody with stability, security and support. It will help to keep Melody’s body straight against the back of the seat since she is unable to control her bodies own motor function. The wheelchair will also be designed with a wide base so that it will not tip and fall 17

over easily. Additionally, the wheelchair is being designed with a disc braking system that allows for instantaneous stopping at any time.

3.7

Social

Socially, we are unable to meet with Melody and the rest of the Kettle family on a regular basis because of the relatively large geographic distance between their home and the University of Connecticut. We would like to spend as much time with Melody as possible and make sure the chair is perfectly customized in each step of the design process. Unfortunately, because of the distance, we must communicate with the Kettle family on the phone or through email. Though, we will still make as many visits to Kettle home as possible. Additionally, Melody seems to thrive when she is outdoors. She is socially more interactive when she is in her backyard or enjoying other outdoor areas. Having an all-terrain wheelchair that allows her to thoroughly experience nature and the elements will most certainly improve her quality of life and will bring joy to her family members.

4

Safety Issues

Melody’s safety is the number one concern in the design of this all-terrain wheelchair. All of the mechanical components of the wheelchair that are being built by our design team must be properly crafted. They will be properly tested within the design lab, by students and eventually by Melody, to ensure the wheelchair meets all of the recommended safety standards.

4.1

Mechanical

The mechanical components of the wheelchair must be extremely safe so that Melody’s health and well-being are never compromised. The wheelchair must be stable to withstand all types of terrain (uneven, rocky, wet, etc). A solid chassis and larger (mountain bike-like) wheels will be used to provide maximum stability. The chassis must be a solid so that it can support Melody’s weight. If not properly built and tested, the chassis could break at any time; causing Melody potential grief and injury. The wheels must be durable and have the ability to withstand all types of terrain and weather. All of the subunits of the wheelchair must be properly mounted or attached to the final project so that nothing will falter or fall off during use. For example, if one of the wheels fell off while in use, the wheelchair could become exceedingly unstable and fall over. An unforeseen fall could be detrimental to Melody and we would never want to see this happen. This wheelchair is designed so that Melody is stabilized when in use. The safety harness will keep Melody in almost a 90 degree position (straight to the back of the seat) at all times. The seat back will be well-cushioned so that Melody’s skin is not abraded or invaded.

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5

Impact of Engineering Solutions

We suspect there are thousands of people like Melody who are completely dependent on their caregivers and require wheelchairs for their everyday lives. There is a huge market for customized, all-terrain wheelchairs. If we can design and create this wheelchair for Melody, we can design it for anyone. The key to successful future use is in determining how to most cost-effectively create customized all-terrain wheelchairs. Once we create Melody’s wheelchair, we will know what materials to use and how to make the most of our budgetary constraints. We hope be able to manufacture future wheelchairs at a significantly reduced cost. This wheelchair has the potential to positively impact the lives of so many disabled individuals. Traditional manual wheelchairs are really only made for the indoors. We have the ability to introduce disabled individuals to a whole new world through an all-terrain wheelchair. We will give them the ability to go outdoors. Disabled individuals with more function than Melody might be able to go outdoors on their own, further increasing their autonomy and improving their quality of life.

6

Life-Long Learning

The design team has learned so much not only from Melody but also from the entire production process. Most of us were not familiar with anoxic brain injuries and had no idea what impact it could have on a person and family. We have gained an incredible appreciation for the selfless work that Mr. and Mrs. Kettle do on a daily basis in caring for their daughter. We have also realized just how fortunate we are to be able to go to school and pursue our dreams. Melody’s family would probably give anything to have the same opportunities for Melody. We have also learned many mechanical skills that will help us in all of our future careers. This project has been an incredible learning experience to all of the members of our group.

6.1

Social

When we began this project, we were individuals who were selected to work together on a project. We, like the wheelchair, were a group of subunits. We learned to work together cohesively and effectively. We developed strong social skills to effectively communicate with Melody’s family. We needed to establish a strong rapport with the Kettle family so they would know we had the best intentions when creating an all-terrain wheelchair for their daughter. We divided tasks to make the most of our time, though we always kept in constant communication so that we were always on the same page. We had to be organized, detail-oriented and efficient so that we could develop the best product possible for Melody. This project was successful because of our teamwork and because off the inspiration we derived from Melody and the entire Kettle family. Each of us wanted to help Melody as much as possible. She has a special place in each of our hearts.

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6.2

Educational

Melody suffers from the complications of an anoxic brain injury. As most group members were unfamiliar with this condition, we researched the condition and became much more educated on anoxia and its complications. We also educated ourselves on how to effectively adhere to budgetary constraints within a project. We learned how to interact with family members, company owners (when asking for donations) and team members. We also had to familiarize ourselves with how to most effectively present this project in a group setting.

6.3

Mechanical

Since the wheelchair had to be created from multiple different parts, it was imperative that the team members used how to effectively use different tools and power equipment. Additionally, some members learned how to weld and cut various metal types. It was important for the group to learn how to use different tools and power equipment. Building the all-terrain wheelchair significantly improved the overall mechanical skills of all group members.

6.4

Software

In order to successfully complete the design and development of Melody’s all-terrain wheelchair, all group members had to become more familiar with some engineering computer programming. For the chair’s initial design, it was essential to learn Solidworks, a CAD program that allows for 3-D modeling and simulation of mechanical components. Having a computerized, 3-dimensional image of the wheelchair facilitated the actual creation of the wheelchair.

7

Budget

In order to build Melody’s all-terrain wheelchair, most of the parts will need to be custom ordered. Melody’s father has graciously supplied us with one of Melody’s older wheelchairs that can be used for parts. We will also be contacting several manufacturers to see if anyone will donate parts for the chair. The more parts that are donated, the better off we will be. The estimated budget for the wheelchair is $1,105.11, as seen in Table 1 below.

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Table 1. Estimated off-road wheelchair budget costs 7.2

Timeline

The following table (Table 2) shows an Excel version of the timeline for this workstation project that was created in Microsoft Project. The full version can be found on the team website. (https://www.bme.uconn.edu/sendes/Spring13/Team1/Project %20Timelines.htm)

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Task 1 2 3 4 5 6 7 8 9 10

8

Task Description Duration Start Design Wheelchair 15 Days 9/12/2012 Design Shock mount assembly 3 Days 10/8/2012 Design quick release socket assembly 1 Day 10/17/2012 Order parts 1 Day 10/18/2012 Pick up parts 1 Day 10/31/2012 Machine quick release socket assembly 4 Days 10/24/2012 Machine shock mounts 5 Days 1/7/2013 Build wheelchair frame 5 Days 1/15/2013 Assemble wheelchair 7 Days 1/23/2013 Test Wheelchahir 10 Days 2/5/2013 Table 2. Timeline for Melody’s all-terrain wheelchair

Finish 9/26/2012 10/11/2012 10/17/2012 10/18/2012 10/31/2012 10/29/2012 1/14/2013 1/21/2013 2/4/2013 2/18/2013

Team Members Contributions to the Project

As our team was involved in several different projects, it was important to identify a team leader for each project. Brandon was chosen to be the team leader on this specific project, though every team member participated thoroughly in the design and creation of an all-terrain wheelchair. Every team member went to meet Melody and her family. The entire group also went to the NEAT Marketplace to choose wheelchair items that could be used for the project. Every member also helped with the optimal design and final design papers. 8.1

Brandon Calavan

Brandon was chosen as the team leader because he has both a medical and a construction background. He served in the military as a flight-medic (where he worked with many brain injured patients) and his grandfather owned a machine shop that he learned in. As such, he was the obvious choice for team leader for this project. He did most of the design of the wheelchair and frame. He researched the parts and worked on all the reports for this project. He ordered all the parts and worked on machining the quick release socket. He also did the CAD modeling for the shock system. 8.2

Ana Groff

Individually, Ana’s organizational skills were extremely beneficial to the project. She kept a meticulous log of the budget, parts ordered and due dates for specific tasks. She also ensured the entire group was in constant communication. Ana helped work on the design of the hub with the quick release socket. She researched stock aluminum parts for the frame and worked on the design for the bearings.

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8.3

Steve Benn

Steve helped a great deal with the initial design of the wheelchair, specifically with the design of the brakes. Both his computer skills and expertise with SolidWorks were key in the design process. He researched and purchased parts at NEAT (axles, basket, shocks (didnt buy)). 8.4

Sebastian Pineo

Sebastian helped with the physical building of the wheelchair. Sebastian went to purchase the wheelchair subunits at NEAT Marketplace (axles, basket, oxygen tank holder). He also helped with initial designs of the off-road wheels. His participation in the workshop, especially with machining, was extremely helpful. 8.5

Dylan Rinker

Dylan helped to order all of the many parts throughout the entire design and building process. Prior to the ordering, Dylan spent a great deal of time researching what parts would be best to order for the project. He helped in the initial design of the wheelchair. He also went to NEAT marketplace to view available wheelchairs and parts.

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Conclusion

Prior to suffering an anoxic brain injury, Melody Kettle was a happy, healthy, well-developed baby girl. Her life was forever drastically changed at 18 months of age. All the hopes and dreams Melody’s parents had for their little girl’s life were taken away by a prolonged seizure. Despite all of the challenges Melody and her family have endured due to her anoxic brain injury, Melody does thrive. She enjoys her family and her family loves spending time with her. Her severe disabilities have confined Melody to her wheelchair. The wheelchair is her life. It is her means of transportation, oxygenation, communication and stimulation. By developing a wheelchair with the components described above, Melody and her family will enjoy more freedom than they ever have. Melody will be able to enjoy the outdoors more frequently, and with ease. She will be able to enjoy a life filled with more nature, vibration, stimulation and improved independence.

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References

[1] “Hippocampe All Terrain Wheelchairs New Feature”. Scooter Direct. . [2] “Tetra Lipo Smart”. Stricker Handbikes. .

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[3] Rackly, John W. All-terrain wheelchair. United States Patent number 7900945. Filed October 29, 2008. Issued March 8, 2011. . [4] Oxford, Stuart G. All-terrain wheelchair. United States Patent number 75149118. Filed October 9, 1990. Issued September 22,1992. . [5] “BergmÃnch, the Bicycle that Folds into a Rucksack”. Treehugger. . [6] Lupin, Francisco. All Mountain Wheelchair. Coroflot: May 8, 2010. . [7] “Nashbar Mechanical Disc Brake Set”. Bikenashbar.com. . [8] “Polaris Shocks”. Fox. . [9] “Wheelchairs - Information and Reviews”. Disabled World. . [10] “Comfort-Flex Chest Harnesses – Flexible & Vinyl-Clad”. Healthwares. < http://www.healthwares.com/documents/MSRP-Harness-ChestShoulder.pdf>.

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Acknowledgments

This project was made possible by the help of many outside sources and generous donations. It has been a privilege to meet and work with Melody and the entire Kettle Family. We are ever so grateful that they initially contacted the UCONN Biomedical Engineering Program. They have shown us the reality of traumatic brain injuries. They have also educated us on what it means to truly sacrifice and have unconditional love for their family member. They have made us want to be better people and better engineers. We would also like to acknowledge Dr. Enderle, our professor, for his constant advice and support throughout the entire design process. His expertise and guidance has been invaluable. We also owe a great deal of gratitude to Dave Barrow, owner of Tolland Bicycle, for his considerable donations of wheelchair parts and labor. We are fortunate that he shared his knowledge of bicycle parts and equipment with us. Lastly, we are indebted to Serge and Pete in the UCONN Engineering Machine Shop as they spent countless hours teaching us how to properly use the equipment for our project. They also helped us in the actual machining of many parts.

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Appendix

12.1 Updated Specifications Technical Specifications

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Wheelchair: Quickie Zippie Iris Tilt Mechanical Material (Frame): Size (Frame): Weight: Weight capacity: Electrical Wires:

T-6061 Aluminum Width (wheel-to-wheel): 22 inches Depth: 34 inches 22 lbs 150 lbs Head switches programming Vibratory stimuli (battery)

Environmental Operating Environment: Storage Temperature: Operating Temperature:

Indoor, Outdoor, Dust, Humidity -10 – 120 °F 20 – 110 °F

Software User Interface: Hardware Interface:

Head switch Controls Power supply component

Safety

Maintenance

Harness/Lap belt security Braking System Shocks Neck, trunk, and leg support Easily fixed Allows room for growth Able to be transported

12.2 Purchase Requisitions and Price Quotes

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