Element B Score 5 Ergo Corture Project

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1 Element B Score 5 Ergo Corture Project EXAMPLES & RESOURCES This entry received a score of 5 independently from a pair of expert raters who are both engineering educators based on the EDPPSR. Documentation of plausible prior attempts to solve the problem (that the people who use current walk-assist devices often do so with poor posture and impeded gait, and may experience further injury) is drawn primarily from a patent search. The analysis of various past attempts to solve the problem through some form of walker is based on clear criteria established by the students, including stability, maneuverability, comfort, durability, safety, indoor-outdoor dual-use capability, height and adjustability, cost, impact to gait, aesthetics, and storage capacity. Discussion is then widened to consideration of other assistive devices currently available that might address the problem. Throughout the entry, relevant data is included and presented objectively as support. Engineering Design Process Portfolio Scoring Rubric Component and Element Titles Component I: Presenting and Justifying a Problem and Solution Requirements Element A: Presentation and justification of the problem Element B. Documentation and analysis of prior solution attempts Element C. Presentation and justification of solution design requirements Component II: Generating and Defending an Original Solution Element D: Design concept generation, analysis, and selection Element E: Application of STEM principles and practices Element F: Consideration of design viability Component III: Constructing and Testing a Prototype Element G: Construction of a testable prototype Element H: Prototype testing and data collection plan Element I: Testing, data collection and analysis Component IV: Evaluation, Reflection, and Recommendations Element J: Documentation of external evaluation Element K: Reflection on the design project Element L: Presentation of designer s recommendations Component V: Documenting and Presenting the Project Element M: Presentation of the project portfolio Element N: Writing like an Engineer Please Note: Elements M and N require no submission from the portfolio author(s) and are intended to be scored based on the portfolio work as a whole from what has been submitted from Elements A through L

2 Element B: From the Engineering Design Process Portfolio Scoring Rubric (EDPPSR) EXAMPLES & RESOURCES Element B. Documentation and analysis of prior solution attempts 5 Documentation of plausible prior attempts to solve the problem and/or related problems is drawn from a wide array of clearly identified and consistently credible sources; the analysis of past and current attempts to solve the problem including both strengths and shortcomings is consistently clear, detailed, and supported by relevant data. 4 Documentation of existing attempts to solve the problem and/or related problems is drawn from a variety of clearly identified and consistently credible sources; the analysis of past and current attempts to solve the problem including both strengths and shortcomings is clear and is generally detailed and supported by relevant data. 3 Documentation of existing attempts to solve the problem and/or related problems is drawn from several but not necessarily varied clearly identified and generally credible sources; the analysis of past and current attempts to solve the problem including both strengths and shortcomings is generally clear and contains some detail and relevant supporting data. 2 Documentation of existing attempts to solve the problem and/or related problems is drawn from a limited number of sources, some of which may not be clearly identified and/or credible; the analysis of past and current attempts to solve the problem including strengths and/or shortcomings is overly general and contains little detail and/or relevant supporting data. 1 Documentation of existing attempts to solve the problem and/or related problems is drawn from only one or two sources that may not be clearly identified and/or credible; the analysis of past and current attempts to solve the problem including strengths and/or shortcomings is vague and is missing any relevant details and/or relevant supporting data. 0 Documentation of existing attempts to solve the problem and/or related problems is missing or minimal (a single source that is not clearly identified and/or credible) OR cannot be inferred from information intended as analysis of past and/or current attempts to solve the problem.

3 II.3 Benchmarking of Competitive Products Five different types of walkers were benchmarked against each other to establish a baseline for walker performance. Each walker was assessed in 11 categories: stability, maneuverability, comfort, durability, safety, indoor-outdoor dual-use capability, height and adjustability, cost, impact to gait, aesthetics, and storage capacity (the source of all data used in Section II.3 can be found in Table II.3.1 in the Appendix). The walkers used in the benchmarking exercise are shown in Figures II.3.1 to II.3.6 below. Figure II.3.1: The Drive Medical Supreme Aluminum 3- wheeled Rollator (Competitor 1). Figure II.3.2: The Ez2Care Deluxe Two-Button Folding Walker (Competitor 2). Figure II.3.3: The Drive Medical Deluxe Two-Button Folding Universal Walker (Competitor 3).

4 Figure II.3.4: The Basic Foldable Walker Rollator (Competitor 4). Figure II.3.5: The Hugo Portable (4-Wheel) Rolling Walker with Seat (Competitor 5). Figure II.3.6: The Red Dot Two-Button Folding Walker Without Wheels (Competitor 6). Each walker was evaluated using the 11 criteria above by studying customer reviews and examining the product specifications. The product specifications provided objective, quantitative information about each walker, while the customer reviews provided subjective, qualitative information. Therefore, the next two sections will show the objective and subjective data differently. II.3.1: Objective Benchmarking Data Several of the 11 original benchmarking criteria can be assessed in a qualitative fashion. For example, the weight capacity that each walker can support impacts the stability of the walker. Similarly, maneuverability is determined partially by the weight of the walker itself, the

5 wheel size, and the size of the walker itself. The adjustability of the walker is described by its range of height adjustments, and price is clearly an objective criterion. Therefore, Table II.3.1, below, shows the specifications for each walker. Table II.3.1 Competitor 1 Competitor 2 Competitor 3 Competitor 4 Competitor 5 Competitor 6 Weight Capacity (lb.) Weight of Walker (lb.) Wheel Size N/A (in.-diameter) Walker Footprint 24 x x 8 21 x x x x 16 Dimensions (in.) Height Range (in.) Price ($) Table II.3.1: Objective benchmarking data for Competitors 1 through 6. Table II.3.2, on the next page, shows the rankings (from one to six) of how each walker performs with respect to the other walkers. This ranking assumes that a six out of six is the best ranking possible, and that a one out of six is the lowest ranking possible. A walker with a larger weight capacity is given a higher ranking than a walker with lower weight capacity, as walkers with higher weight capacities allow more consumers to use them. Users also prefer lighter walkers, so a walker will rank higher if the weight of the walker is lower. Smaller wheels promote more maneuverability, so a walker with smaller wheels will be ranked higher than a walker with larger wheels. Similarly, a walker with a smaller footprint will be more maneuverable than a walker with a larger footprint, so a walker with a smaller footprint will rank higher. A walker with a larger height range will rank higher than a walker with a smaller height range, and a walker with a lower price will rank higher than a walker with a higher price. If two competitor products have the same value for one criterion, each product will receive the same ranking. The results are shown in Table II.2.3.2, below. Table II.3.2 Competitor 1 Competitor 2 Competitor 3 Competitor 4 Competitor 5 Competitor 6 Weight Capacity (lb.) Weight of Walker (lb.) Wheel Size (in diameter) Walker Footprint Dimensions (in.) Height Range (in.) Price ($) Table II.3.2: Objective criteria comparison rankings for Competitors 1 through 6. II.3.2: Subjective Benchmarking Data The level of stability that the user feels while using the walker, how maneuverable users perceive the walker to be, the impact that the walker has on the user s gait, the comfort of using the walker due to the handle construction, the comfort of using the walker due to the posture the user maintains while using the walker, the durability of the walker, the safety of the walker, the capability of the walker to be used indoors and outdoors, and the reliability of the walker are all subjective criteria. Customer reviews for each walker were read by members of the design team, and performance of the walkers with respect to each criterion

6 were rated on a scale of one to five (five being the best rating). The results are summarized in Table II.3.3 to Table II.3.8, below. Table II.3.3 Rating Comments Stability 3 Decreased balance is an effect of increased maneuverability. Maneuverability 5 Most maneuverable type of walker on the market. Impact to Gait 4 Three wheels make walking easier. Handle Comfort 2 Handles made of hard plastic. Impact to Posture 5 All contact points are wheels, making it harder for users to lean over while using. Three wheeled base allows users to walk closer to walker. Durability 5 Constructed from large-diameter aluminum tubing. Safety 4 Brakes and wheel locks add to safety. Indoor/Outdoor Use 5 Large wheels allow for indoor and outdoor use. Aesthetics 5 Looks very different from a traditional walker. Storage Capability 5 Large storage case on rear of walker. Table II.3.3: Subjective benchmarking data for Competitor 1 (Drive Medical Supreme Aluminum 3-wheeled Rollator). Table II.3.4 Rating Comments Stability 4 Users report good balance. Maneuverability 3 Wheels do not swivel, but wheels on front allow walker to be pushed without being lifted. Impact to Gait 3 Harder to push than three or four wheeled walkers. Handle Comfort 3 Hard vinyl handgrips can cause pain. Impact to Posture 3 Users tend to lean over while using walker. Durability 4 Users report high quality construction. Safety 4 Rubber tips on back of walker can stabilize walker while in use. Indoor/Outdoor Use 3 Wheel diameter is too small to navigate over large cracks or bumps. Aesthetics 2 Looks like a typical medical walker. Storage Capability 2 None present, but can buy walker

7 bags to add on. Table II.3.4: Subjective benchmarking data for Competitor 2 (Ez2Care Deluxe Two-Button Folding Walker). Table II.3.5 Rating Comments Stability 3 Users say the walker feels rickety. Maneuverability 3 Non-swiveling wheels limits mobility. Impact to Gait 3 r to push than three or four wheeled rs. Handle Comfort 3 Hard vinyl handgrips can cause pain. Impact to Posture 2 Users tend to lean over while using walker. Durability 2 Aluminum frame is durable but buttons and mechanisms associated with folding often break. Safety 4 Two release buttons prevent walker from folding during use. Indoor/Outdoor Use 3 Rubber wheels have a hard time navigating on hard surfaces. Aesthetics 2 Looks like a typical medical walker. Storage Capability 2 None present, but can buy walker bags to add on. Table II.3.5: Subjective benchmarking data for Competitor 3 (The Drive Medical Deluxe Two-Button Folding Universal Walker). Table II.3.6 Rating Comments Stability 5 Rear wheels have foot-activated brakes to prevent slipping. Maneuverability 5 Easy to maneuver due to swivel wheels in front. Impact to Gait 5 Four wheels allow more normal gait than two wheeled walkers. Handle Comfort 5 Padded handgrips and seats. Impact to Posture 3 Users tend to lean forward and push the walker ahead of them. Durability 4 Users rate the durability as 4.75 out of 5 on Walmart website. Safety 5 Foot-activated wheel brakes lock for safety. Indoor/Outdoor Use 4 Can be used both indoors and outdoors, but should limit outdoor use (wheels can be damaged). Aesthetics 4 Attractive color, modern appearance. Storage Capability 5 Storage basket underneath seat

8 Table II.3.6: Subjective benchmarking data for Competitor 4 (The Basic Foldable Walker Rollator). Table II.3.7 Rating Comments Stability 3 Slides when brakes are not applied Maneuverability 3 Heavier than most walkers. Less maneuverable than three wheeled walkers. Impact to Gait 5 Four wheels allow more normal gait than two wheeled walkers. Handle Comfort 5 Padded handgrips and seats. Impact to Posture 3 Users tend to lean forward and push the walker ahead of them. Durability 5 Solid construction. Can hold up to 300 pounds. Safety 4 More prone to slipping, but handbrakes are included. Indoor/Outdoor Use 5 Can be used both indoors and outdoors. Aesthetics 4 Bright color, modern appearance. Storage Capability 5 Storage bag beneath the seat. Table II.3.7: Subjective benchmarking data for Competitor 5 (The Hugo Portable (4-Wheel) Rolling Walker with Seat). Table II.3.8 Rating Comments Stability 5 Walker more stable than one with wheels. Maneuverability 3 Can easily fit through doors, but lifting and walking can be inconvenient. Impact to Gait 1 Walker too narrow for some users, lifting walker can interrupt normal gait. Handle Comfort 4 Rubber handles are commonplace. Impact to Posture 2 Lifting and moving can only occur for short distances. Durability 5 Can bear significant weight, few moving parts. Safety 4 Very slip resistant. Indoor/Outdoor Use 5 Usable both indoors and outdoors. Aesthetics 2 Looks like a typical medical walker. Storage Capability 2 None present, but can buy walker bags to add on. Table II.3.8: Subjective benchmarking data for Competitor 6 (The Red Dot Two-Button Folding Walker Without Wheels). II.3.3: Summary of Results Stability

9 o Objectively, the walker must have a weight capacity of between 250 and 400 pounds. o Subjectively, the users must be able to trust that the walker will provide them with good balance and a solid foundation. Maneuverability o Objectively, the walker must be light-weight (between five and nine pounds), have a small wheel diameter (five to seven inches), and the walker must have a small footprint (between 160 and 330 square inches). o Subjectively, the user must be able to navigate the walker through doorways, between furniture, and in tight spaces while never having to back-out of a hallway or confined area because their walker will not turn. Comfort o Elderly users walk with their walkers at all times when they are standing. The handgrips must therefore be comfortable enough that the user can use their walker for long periods of time. o The walker must also ensure that the user is walking with good posture so as to ensure that no harm is done to the user s back or shoulders. Walking with bad posture can cause upper-body pain and discomfort among users. Durability o The walking frame must be durable. Users want to purchase a walker that will last for several years. Safety o A walker must be safe to use. Brakes are very helpful in ensuring that the walker does not slide away from the user unexpectedly. Indoor-outdoor Dual-use Capability o Users must be able to use their walker both inside and outside of their home. The wheels of the walker, if any are included, must be durable enough to handle rough outside surfaces and large enough in diameter to navigate over bumps and cracks. Height and Adjustability o The walker must be adjustable in height to satisfy the needs of customers of any size. The best height range found in the products in the bench-marking exercise was 28 to38 inches. Cost o While some users may pay more for a walker that is a better quality design, the price of the newly designed walker must remain close to the price of the competitors. The average competitor price is approximately 71 dollars, therefore the new design should be priced reasonably close to 71 dollars (in a range of 40 to 100 dollars). Impact to Gait o Changing a user s gait can cause tripping, poor posture, and slow walking speed. Therefore, the new design should not impact the user s natural walking gait. The four- and three-wheeled walkers have the lowest impact to the user s natural gait. Aesthetics o As discussed in Section II.2.1 above, elderly individuals often resist using walkers that look like assistive devices. Therefore, the new walker design should have an attractive, modern look. If the walker s appearance appeals to the elderly, they will be more likely to use it.

10 Storage Capacity o Users enjoy the ability to store things in their walkers, especially because using a walker causes individuals to lose the use of their hands. Adding a basket, bag, or tray to the new design will help users keep their hands free while walking. II.4 Patent Search To gather more information regarding the walker and assistive devices market space, six patents were studied to determine the options for providing support to elderly individuals while they walk. Five types of products were studied: two medical walkers, one baby walker, one support harness, one back brace, and one weight suspension device. These patents were studied because each device brings aspects that can be applied to the new walker design. Each of the next six sections will discuss the search process method for finding the six patents, why the patents apply to the design, and a description of each patent. II.4.1 US A: Adjustably Controllable Walker The main category under USPTO that directs to walkers is Patent Class 135: Tent, Canopy, Umbrella or Cane. Under that class is subclass 65: Canes, Sticks, Crutches, and Walking Aids; down another subclass is 67: Walker type, where various walker patents may be found. The search was specifically looking for a walker function that the team s design may utilize, such as a braking mechanism for wheeled walkers. Lightness and stability (as well as added features) are often traded off in non-wheeled walker designs to make shuffling a walker more manageable. This problem is alleviated in walkers equipped with wheels, so that lifting is not necessary. This allows for the installation of additional features, such as seating or supports, for a more ergonomic walker. Since walkers are often used for balance and to prevent falls, wheeled walkers should possess controllable brakes so that they do not accidentally slip away. The new walker design could incorporate brakes to ensure safety and stability of the walker. This patent specifies a wheeled walker with braking capabilities. The patent s descriptions are written generally to encompass mechanical and electrical braking mechanisms. The Figure II.4.1.1: Patent No US A. general geometry of a walker is described as including vertical support members and at least one horizontal support.

11 The novel concept is the inclusion of an actuator and a stabilizer for a controllable brake. The brake functions with two settings: passive and active. Passive indicates a stable state in which the walker does not move, and active indicates a mobile state. The patent mostly references an enbodiment in which the stable state is when the brakes are engaged, and the mobile state is when the brakes are released; the reverse is also possible in which walker is normally mobile and only fixed when the brakes are engaged. The control system includes some actuator for the brakes. Besides a button or switch as indicated in label 50 of Figure II.4.1.1, the actuator could utilize a pressure sensor (likely a strain gage) to obtain the distributed forces applied by the operator, which then actuates an electrical circuit connected to the brake mechanism. The pressure necessary to engage/disengage the brake can be calibrated to suit the operator. Figure II displays a generic walker with braking capabilities (features such as the number of legs and location of the actuating mechanism may vary). The four vertical supports 12, 14, 16, 18 can be clearly seen. Feet 32, 34, 36, and 38 may include rubber or some other material with high static friction to secure the walker. The brake actuator, 50, is generalized as a switch located on the horizontal cross bar, 20. When the switch is closed, solenoid brakes 42, 44, 46, 48 are powered. Assuming this electrical braking configuration, a microcontroller would determine when enough pressure is applied to activate/deactivate the solenoids. Strengths: The main advantage presented in this patent is the ability to adjust the braking capabilities according to the differing needs of users. Not only can it be adjusted for different patients, the walker can be calibrated to brake at different applied pressures for the same patient undergoing rehab and improving in condition (relying less and less on walker), or for an elderly person becoming more reliant on walking aids. Weaknesses: This design may not cover all the possible situations that necessitate braking. For example, a push forward may still cause the walker to slip away if the braking mechanism is designed to be off until actuated by a sufficient downward applied load. The braking functions may also be too costly, or too heavy. II.4.2 US A: Wheeled Triple-Leg Walker The search process that led to the discovery of this type of walker focused on finding walkers that were rated the highest in the combined categories of stability and maneuverability. By searching for customer reviews of walkers, the three-wheeled model was found to be rated highest in both categories. Then, the design team searched specifically for three-wheeled walker patents. The classification system was not used to find the patent. In a study performed by R. Anslow et al., three-wheeled walkers were found to be the most maneuverable in a comparison between, two-, three-, and four-wheeled walking frames. The three wheeled walkers were rated just as high as two- and four-wheeled walkers in stability. This design could provide as a good example of a walker that is both easily maneuverable and highly stable, and lessons from this three wheeled walker can be applied to the new design.

12 Figure II.4.2.1: Patent No. US Ching-Tien Pi s US patent (published December 21, 1999) is for a three wheeled mobility aid. This walker design uses three wheels (30) that are fixed to the frame, but will be allowed to turn when a downward pressure is applied through the leg (31). The walker uses a frame that is made up of four members, two of which connect the wheel assemblies and the arm rests (55) and two of which are used to improve the stability of the structure. This particular walker uses arm-rests to support the users weight and are tilted at an angle to allow the user to push the frame forward. The walker also has a collapsible seat (47) that can be connected to the cross members. Strengths: The three-wheeled design allows the frame to be narrower which allows users to easily maneuver the walker around obstacles in an indoor environment. The arm rests allow the users to comfortably rest their weight on the walker and alleviates the danger of ulnar palsy from holding the hand grips. Weaknesses: The narrower frame may mean that the stability is compromised. Also the design that allows the wheels to turn could be difficult for lighter patients to use. Though the arm rests allow the user to comfortably rest their weight on the device, they encourage poor posture that can lead to back problems. II.4.3 US : Dual Function Baby Walker The search process began by using the classification guide that was shown in class on Tuesday, September 10. Baby walkers fall under two classifications: vehicle (280) and with seat (297). Searching further in those classifications, baby walkers under vehicles are placed within several more subsets. Baby walkers are land vehicles (280) that are wheeled coasters (29 and 87.01) and are occupant pushed (87.021). Under occupant pushed, one can find baby walkers (87.051). Baby walker patents were then found using the Google Patent Search Tool. When the dual function baby walker patent (US ) was selected, the US Patent and Trademark Office website was used to view the official documentation and to ensure that this patent falls under the classifications that found earlier.

13 The Dual Function Baby Walker Patent, United States Patent B1, is relevant to the design of a more ergonomic walker for the elderly because the baby walker has two modes of support for young children at different stages of development. The baby walker has a seat that infants can sit in while they are first learning to walk and cannot yet support their full body weight (Figure II.4.3.1). The seat, however, allows infants to push against the ground with their legs and propel themselves so that they can begin developing the leg strength and motions associated with walking. The seat and undercarriage can also be detached so that toddlers, who are more advanced at walking, can walk upright. A handle is added to the rear of the walker so that toddlers can push against the walker for support while they are walking upright (Figure II.4.3.2). This dual function aspect could be adopted in our design for a more ergonomic walker for the elderly. In order to satisfy the needs of elderly with different levels of mobility, we will need to ensure that our ergonomic walker has a mode to help remove some of the user s body weight if their legs are not strong enough to hold them upright and a mode to provide assistance for those users who can support their body weight but rely on the walker for balance. The ergonomic walker could also be helpful to individuals who are recovering from an injury, such as a fall. As the individual begins to rebuild leg strength, they can change the ergonomic walker from a mode that supports a portion of their weight to a mode where the walker is used only for balance. Jung Chih Wu s US B1 patent (published May 15, 2001) describes a dual function baby walker. This baby walker contains a seat (item 3.1 in Figure II.4.3.3), restraint (3.2) and undercarriage (3.3) to hold an infant in place while he/she propels the walker with their feet. The seat allows the infant s legs to touch the ground, the restraint prevents the infant from falling out of the walker, and the undercarriage allows for smooth motion. The seat (3.1) and undercarriage (3.3) can be detached and wheels (3.4), a handlebar (3.5), and a seat pan (3.6) can be attached so that a toddler can walk while supporting most of his/her own body weight. The toddler can push against the handlebar (3.5) to propel the walker while using it to maintain balance. The undercarriage (3.3) is replaced by studier wheels (3.4) so that the walker is lowered to a height at which the toddler can use the walker much like an elderly individual uses a walker. The seat pan (3.6), held in place by the support (3.7), ensures that one child cannot become trapped inside the restraint while another child is pushing the walker. It also allows a toddler to safely and securely load the seat pan (3.6) with toys and push the walker as if it were a baby s stroller.

14 Strengths: The patent s strengths stem mostly from the walker s dual function. Since the walker can be used for young children at multiple stages of learning how to walk, parents do not have to buy multiple walkers for one child. Children can use the same walker as infants and toddlers, saving parents money and adding value to the product. The restraint (item 3.2 in Figure II.4.3.3) ensures that the child remains safe during use. Since the restraint wraps 360 degrees around the child, it is very hard for a child to fall out. The wide undercarriage also adds stability to prevent the walker from tipping over. The walker is also designed to look like a car, which is appealing to children, especially young boys. Children will want to use their walker because it looks similar to a car that their parents drive. The young users will enjoy the ability to be imaginative while using the carshaped walker, and will enjoy that they can fill the seat pan (3.6) with toys to push around. Weaknesses: While the dual function aspect helps parents save money, it also requires significant disassembly and reassembly. To change from the seated walker to the pushing walker, parents have to remove the seat and undercarriage, and then install the handlebars, support, seat pan, and wheels. While this is not a big issue if parents are only changing the walker once, it could get tedious for a child who is in between being able to stand on his or her own and needing the seat. During that in-between phase, parents may have to change modes quite frequently. This is especially necessary when parents do not have the time to watch their child s every move. Removing and attaching the different parts to change the walker s function could also cause the parts to degrade. The more often that parents switch functions, the more likely it is for parts or connections to become damaged. A second weakness stems from the lack of a seat belt in the walker. Most, if not all, strollers have belts to make sure that the child stays securely in their seat. This walker, however, has no restraining belt, which could allow infants to slip out of their seat while using the walker in the seated mode.

15 II.4.4 US : Floating Harness This patent was found by searching directly for harnesses worn by firefighters. The classification system was not used to find this patent. The idea behind current walkers is that the user uses their upper body strength to support the rest of their body. This is usually accomplished through the user leaning forward and holding onto two grips attached to the walker frame. The design team wants to develop a walker that puts the burden of supporting weight on the walker without utilizing the user s upper body, similar to how harnesses use the midriff of the user to support their body weight. Figure II.4.4.1: Patent No. US The patent by Mark Mordecai, Julie Snedeker, and John Yates (published October 9, 2012) is for fully supporting a person who is not standing on the ground. The harness consists of one strap of constant diameter that slides over one leg and another adjustable strap for use over the other leg. This harness, aimed for use with firefighters, can be easily attached to a firefighter s suit. Strengths: This harness is small, lightweight, and quick and easy to don. The harness is meant for quickly escaping burning buildings from tall heights, so it was designed to be put on quickly. Previous means of escaping burning buildings from tall heights required the use of bulky rope and harness systems that would not always be carried into a burning building because of the amount of equipment firefighters already bring with them. Weaknesses: A harness like this is perfect for emergency situations. But, in the scope of the design project, the time required to done such a harness is not defined by an emergency situations. This harness would require a sufficient amount of mobility and strength to don with large leg movements and a bent over posture. Comfort is also not a major objective of this design. A firefighter s repel from the top of a burning building would take minutes at most. A walker is designed to be used for an entire day if it has to be.

16 II.4.5 US : Comfortable Back Brace During my search process, the USPTO patent search tool was used to narrow down results down to show only patents which included back brace in the title. This search yielded many results, many of which were viewed before settling on this patent as the final choice. When reading through the patents, the design team looked for a design that provided good support while still keeping user comfort in mind. The team also looked for more recent patents, since the designs of back braces have been improved upon for many years, dating back to the 1970 s. Improving the posture of the walker user is one of the main focuses for this design, as existing walker designs seem to cause poor posture. A comfortable back brace could be added to the walker to help encourage elderly users to stand up straighter. Figure II.4.5.1: Patent No US Willie Neil Johnson s patent (published May 28, 2013) is for a back brace which conforms to the user s back to encourage proper posture, as well as abdomen and lower back support. The adjustable belt (320) can be adjusted by the user to keep the brace secure and ensure that it is offering the proper support without being tightened uncomfortably. The lumbar support panel (210) provides lower back support for the user, while the dome-shaped protrusion (240) matches the contour of the user s back, providing enhanced lumbar support. This is coupled with abdominal support, which is provided by the abdominal support panel (100), which is located inside of the support envelope (120). Strengths: This brace is very useful for lower back support, as it includes features to support the lower back and to ensure that the brace promotes proper back posture using the protrusion. These features could be helpful in improving the posture of walker users if they were incorporated into the new walker design. This may also improve user safety, as the walkers would be less likely to slip out from under the user if they were kept from hunching over and holding the walker farther away from their body. In addition, if this strap was incorporated into the walker in such a way that there was a sturdy connection between the strap and the walker, it could possibly be used to help keep the user upright if they begin to fall over.

17 Weaknesses: This device may not be ideal for use by the elderly due to the necessity to strap oneself into the belt. This may prove difficult for those who suffer from arthritis or similar conditions. Although the strap itself should decrease discomfort in the form of back pain, if it is painful for users to use the straps this would defeat the purpose of increasing comfort and ergonomics. In addition, this device by itself does not really address the issues of stability or maneuverability, which seem to be two of the most important customer requirements for walkers. II.4.6 US : Racing Speed Training and Therapy Apparatus Method This patent was found using the USPTO website s search tool. While this patent is intended to encourage proper speed training for races, the technology lends itself to be applicable to the new walker design as well. The 1993 patent by Richard Bryne uses a frame attached to a belt or harness encircling the user s body, partially suspending him or her, to lower the impact pressure to the knees of the user while running or walking. The new walker design could utilize a similar belt or harness to allow users to walk while supporting less than their full body weight on their legs. The frame of such a device could either be used free-standing, or could be attached to a propulsion means (such as a treadmill or wheels, as seen in Figures II and II.4.6.2) for road training. Bryne described the supports as being adjustable and releasable through the means of a clip or belt, allowing for the maximum comfort and ergonomic benefits for the user. Figure II.4.6.1: This sketch depicts an option of Bryne s design in which the user would be stationary and the device would be used to help the user train on a treadmill. In this picture, the user is secured by a belt around the waist through some rigid supports and some adjustable straps.

18 Figure II.4.6.2: This sketch depicts an alternative design, in which Bryne added wheels to the frame to allow the user to be much more mobile and travel outside. In this illustration, the user is encircled by a rigid frame and attached to the frame via straps connecting to the torso. Figure II.4.6.3: This diagram illustrates a device in which the user is suspended from the frame with a pants-like support device. Presumably the frame itself would be adjustable in height, allowing for the variation in induced body weight. Strengths: Bryne s therapy apparatus permits the user to remain fully upright with proper running/walking form, which is the entire goal of our design of an ergonomic walker. Additionally, Bryne s design is fully adjustable in terms of tension and suspension, allowing for the variation in the user s induced body-weight. Since part of our target market is the physically disabled (perhaps those who are temporarily physically disabled and are undergoing rehabilitation), the ability to learn to walk correctly but without the shock and stress of hitting the ground at full impact would a huge benefit for the customer. Further, the patent includes a design option with wheels, which would be ideal for promoting a user s maximum mobility. Bryne even specified the material qualities of the design, stating that the belt is sufficiently pliable and elastic so that it does not inhibit the [user s] movements, but not so elastic as to permit the [user s] weight to completely overcome the upward forces of the supports. The support straps included in the design are placed so as not to interfere with the user s natural arm swing. Weaknesses: Several disadvantages plague Bryne s design as it applies to our project. While Bryne mentioned clips and belts as a means of securing the user to his device, he was vague about how easy it would be for the user to enter and exit the apparatus. The design team would aim

19 to make the entry to and exit from the device much more user-friendly if implemented in the walker design, in the case that the user would need to transition from a sitting to standing position, for example. The device also seems rather large for everyday use. Even for its intended use of speed training, the apparatus is bulky and would not work well on narrow roads. If the team was to adopt some of Bryne s ideas into the new design, the team would definitely innovate a walker that is much narrower, for the purposes of the user being able to navigate within a home, office, or building. Finally, in order to make Bryne s invention more relevant to the new design, the team would probably add some storage device to our walker, like a basket or bag for holding personal itee II.4.7 Lessons Learned The USPTO separates walkers with seats and walkers without seats into two separate classifications. This separation suggests that the design team should consider incorporating a seat into the new walker. The seat will allow elderly individuals to rest while walking, especially in public places where benches and chairs may not be readily available. The speed training and therapy device patent (US ) demonstrates one way to lessen how much of their own weight that the users must support. For elderly individuals using a walker, a significant portion of their weight is supported by their arms as the hold onto the walker for balance. Alleviating some of the pressure on their arms could make walking with a walker safer and more comfortable. The design team must remember, however, that any harness system must be easy to get in and out of. Unlike a runner who may train for several hours in the speed training and therapy harness, elderly individuals will have to put on and take off the harness tens of times throughout the day to get dressed, bath, and use the toilet. Therefore, the harness should be easy to put on and take off quickly similar to the floating harness (US ). The comfortable back brace (US ) is a great example of a product that promotes proper back posture. A brace that is attached around the back of elderly users will help encourage them to stand up straight and avoid leaning over their walkers. However, elderly individuals would not be able to put on and take off the comfortable back brace (US ), especially if they have arthritis. Individuals who suffer from arthritis and other joint pain are not able to attach small buckles or push adjustable belts through small holes. As the design team develops concepts, it must keep in mind that any harnesses or controls included in the new walker need to be arthritis-friendly. The three-legged walker (patent US ) reminds the design team that three wheeled walkers are the most maneuverable. When designing a new walker, the team may want to consider developing a walker with three legs and three wheels to allow for the best mobility possible. However, the design team must ensure that increased mobility does not mean decreased safety and stability. A walker that is easier to move is good for promoting natural gait and high maneuverability, but a walker that is easier to move is also more likely to slip away from the user. The adjustably controllable walker (patent US A) contains brakes that can help alleviate this concern. Whether the design team includes brakes that are foot activated, hand activated, or automatically activated if the walker experiences large accelerations, brakes will be a key part in ensuring safety and stability of the new walker design.

20 II.5 Opportunities for Competitive Advantage While there are many walker designs currently on the market, there are three needs that current models do not address: limiting impact to natural gait, encouraging correct posture, and providing a more attractive appearance. Many walkers on the market provide good stability, have large weight capacities, are durable and reliable, are priced reasonably, have storage capacity, and can be used both indoors and outdoors. Therefore, from a functional standpoint, there is not much room for innovation to improve the basic walker functions. Walkers designed for increased maneuverability, such as the three and four wheel rollators studied in the benchmarking exercise in II.3, are also numerous. What is currently missing from the walker sales arena is a device that improves the comfort of the user both physically and mentally. Too many users push the walkers too far out in front of them and end up slouching over their walker; and while walkers are meant to be used for assistance, users should still be supporting the majority of their weight with their legs. As stated above and confirmed through the interview with Deborah Catherine, the main use for a walker is to provide balance for elderly individuals not to support their full weight. Prolonged periods of slouching can also lead to back injuries, shoulder injuries, and ulnar nerve palsy. Therefore, there is opportunity for a new walker design to encourage good posture and limit the amount of slouching of the user. As discussed in Section II.1, above, the number of falls that occur while individuals are using walkers is alarmingly high. The high rate of walker related may be related to the impact that the walkers have on users gait. For people who have walked unassisted their whole lives, walking behind a walker feels unnatural. Elderly individuals react to the walker placed in front of them by altering the way they walk, which can lead to falls. Therefore, a walker that allows individuals to maintain their natural gait while using the walker will help to lower the number of walker related falls in the future. While encouraging good posture and uninterrupted gait will help to decrease back injuries and injuries related to falls, it will also help to slow the process by which elderly users become dependent on their walkers. As users begin to change the way that they walk, then walk for days and months using their walker, they will lose the muscle memory of unassisted walking. As they lose this muscle memory, they will become more and more dependent on their walkers and quickly develop a need to use a wheelchair. Encouraging elderly users to walk properly will help them maintain a high level of mobility and strength that can only be kept by walking unassisted. Maintaining the muscle memory and strength necessary for unassisted walking will be particularly useful for elderly individuals recovering from surgery or an injury. Many individuals who have to use a walker after undergoing surgery or suffering a fall become dependent on the walker. A walker that mimics the posture and gait of natural walking will ensure that users can return to natural walking after recovering. An aesthetically pleasing walker design is also a major area for competitive advantage. As discussed in Section II.1 above, many elderly individuals resist using their walker or assistive device because they believe that it makes them look too old. Mrs. Exelbert echoed that belief in her interview. She voiced a need for a walker, cane, or other device that provides the user with balance but does not look like a traditional medically issued artifact. Mrs. Exelbert suggested a product that falls between a walker and a cane. An artifact that falls into this category would have a large competitive advantage because there are currently no products in this space. Being first to market in this blue ocean would ensure that our firm and design

21 attracts customers that would otherwise be difficult to attract if we were directly competing with established firms. There is no question that any new design would have to meet a standard for stability, maneuverability, safety, durability, height adjustability, storage capacity, and indoor/outdoor dual usability. Our walker design will have to function at the same level as the baseline established through benchmarking in order to be a viable option as an assistive device. However, the design team s goal is not to make a higher performing walker with respect to these seven categories. Instead, we will focus on making a walker that encourages correct posture and gait. We will also focus on designing a walker that elderly individuals will want to use. The new walker design will be fashionable and attractive as well as functional so that elderly users will actually be happy while using the device.