Written Communication Assist Device [The Ohio State University]

Molly Baumann, Alex Clark, John Inkrott, David Kerslake, Kevin Metka, & Jenn Wharton

Abstract

A cervical spinal cord injury can change the way a person lives the rest of their life.  Each year, there are approximately 12,000 spinal cord injuries in the United States.  Some of the most common causes of these injuries include motor vehicle accidents, other types of accidents (including falls, violence, and sports), or a spinal tumor or abscess. Depending on the severity of the injury, certain nerve sensations and control of motor movements throughout the arms, hands, and wrists are affected.  This makes performing simple, everyday tasks an enormous struggle without the assistance of another person. While there is no medical procedure to bring back the nerve sensation and control of motor movements, there are medical assistive devices that help improve the ability to perform certain activities.

In the workplace, typing and writing are two essential abilities that someone should posses.  Currently, there are not a lot of assistive devices on the market that help the consumer to perform each of these tasks. These current devices are also difficult to put on without assistance and do not greatly improve the consumer’s ability to write and type.  Therefore, the goal of team Jomokedalexenn is to create a device to improve the written communication skills of individuals with spinal cord injuries.  The scope of this project includes creating a device that will combine these tasks while performing them efficiently, allowing the consumer to independently put on and take off the device, and having the best ergonomics (small, lightweight, and safe) as possible.

Acknowledgements

We would like to thank Kevin Stahr, occupational therapist at Martha Morehouse, for his expert opinion and allowing us to interview potential consumers. We would like to thank Dr. Tanya Nocera, our engineering advisor, and Theresa Berner, occupational therapist and clinical mentor, for their expert advice in developing our project solution. We would also like to thank Dr. Mark Ruegsegger and Dr. Sandra Metzler, our engineering design professors, for bringing this problem to us and teaching us about the design process. We would like to thank the Department of Biomedical Engineering and the Department of Mechanical Engineering at The Ohio State University for providing the necessary resources to design and build our device and for providing assistance as needed. We would like to thank the Department of Biomedical Engineering at The Ohio State University for funding our project.  Finally, we would also like to thank the potential consumers we have interviewed.

Chapter 1

1.1 Introduction

Around the world, between 250,000 and 500,000 people annually are in a situation resulting in spinal cord injury, 12,000 of them in the United States (World Health Organization 2013). Up to 90% of these injuries occur as a result of a traumatic event such as automobile accidents or falls (World Health Organization 2013). Spinal cord injuries impact nerve sensation and control of motor movements throughout the arms, hands, and wrists. Due to the importance of these regions of the body for everyday activities, assistance is usually required for daily living needs (Shepherd Center 2011). People with cervical spinal cord injuries have varying levels of motor control of their hands depending on how severed the cord is. Some individuals can still grasp certain objects and have some control of their hands. Some are able to use compensatory techniques to complete tasks. There are some devices on the market to aid with movements of the hands and wrists such as the Universal Cuff, which allows individuals to grasp objects even though they do not have control over their hands and fingers (North Coast Medical, Inc. 2014, Patterson Medical Holdings, Inc. 2014). There are other devices also on the market to help with everyday activities but these can be expensive, ergonomically inefficient, and not durable. Many of the more used devices currently on the market do not address written communication; the Universal Cuff does not have an attachment to help with writing or typing.

One specific area where cervical spinal cord injured patients who were interviewed by Team Jomokedalexenn would like to see advancement is in written communication devices. These people are involved in handwriting or typing daily in their workplace, so there is a need for improved typing and handwriting for these users. Team Jomokedalexenn will focus on improving both of these areas of written communication by creating a single device that improves both handwriting and typing. This new device will both improve writing and typing speed and accuracy, while also being ergonomically efficient for the user, making it require little energy for usage.

1.2 Problem Definition

1.2.1 Clinical Background

The 12,000 spinal cord injuries in the United State each year are commonly caused by motor vehicle accidents, other types of accidents (including falls, violence, and sports), or a spinal tumor or abscess (National Spinal Cord Injury Statistical Center 2013). These injuries can occur easily due to the C6 vertebra being exposed on the back of the neck. If the neck experiences trauma such as in a collision, the C6 vertebra can be fractured when the neck snaps. Figure 1 shows the location of the cervical vertebrae in relation to the skull and demonstrates that there is a vulnerability there due to the exposure.

Figure 1: Cervical Vertebra Location (SBI 2011)

Figure 2: Dermatomes and Associated Nerve Levels (Filler 2004; Apparelyzed 2003)

The nerves affected by a cervical spinal cord injury also affect other parts of the body. Figure 2 shows the correlation between different levels. For example in green, the C5 and C6 vertebrae affect the nerve and sensation in the hands. Figure 2 shows the different parts of the body affected by the level of the spinal cord injury.

Many individuals with this type of cervical spinal cord injury have some function of their arm, but not their hand. They generally have function of their shoulder and elbow. Their range of motion may be slightly more limited than an individual without the injury, but they are still able to rotate their shoulder and flex their elbow, which gives them some ability to move their arm into a new position. Their fine motor skills are impaired which limits their normal grasp. The injury can cause nerve damage, which is what causes the loss of nerve control in the hand and loss of sensation.

The level of control depends on the nature of the spinal cord injury. There are two different types which have slightly different symptoms. There are complete and incomplete spinal cord injuries. Complete spinal cord injuries mean that the damage in the nerve obstructs all signals below the injury level (Christopher and Dana Reeve Foundation 2014). In incomplete injuries, there is some sensory and motor function spared below the level of the injury. The spinal cord is not completely severed or damaged so some of the signals are able to pass between the brain and the body (Christopher and Dana Reeve Foundation 2014). Incomplete injuries will be the focus of this device because they will have more upper arm function.

There are many functions that people with cervical spinal cord injuries cannot perform that are taken for granted by those unaffected by injury every day. This was a problem that was seen clinically. Those living with a cervical spinal cord injury have limited grasp and cannot hold many items, including a pencil, toothbrush, or razor. This limits their ability to perform everyday tasks independently. They require assistance from an aid or family member to brush their teeth, eat, get dressed, write, and perform other everyday tasks.

There are several other side effects of the cervical spinal cord injury. People tend to have either a very tight hand or a very flaccid hand. This is due to abnormal tone and specificity. This is caused by the nerve damage, which causes the muscles to respond abnormally. The nerves are impaired which results in the muscles contracting abnormally and decreases muscle strength in many cases. The term used to describe a person with a tight hand is tenodesis. Tenodesis is a flexion and compression of the muscles in the hand resulting from how the muscles and tendons are connected to the bones (Adapta Medical 2011). When the wrist is brought up or flexed, the fingers close making a firm grip. When the wrist is brought down or extended, the fingers will open. This needs to be considered because there will be varying levels of ability to hold a device. With a flaccid hand, there will be less ability to grasp. In typing and writing, a flaccid hand cannot grip a pencil and has trouble keeping their hand in position to type. With tenodesis, it may be more difficult to open the hand to grasp an object. They may not be able to grasp a pencil without having help to open their hand first and they may not be able to keep their fingers out to type. People with spinal cord injury often have a loss of sensation, which must be taken into account when designing the device (Shepherd Center 2011).  This loss of sensation is due to the severing or pinching of nerves in the spinal cord. With loss of sensation, the consumer loses the ability to feel some textures. If the device has a sharp edge, the user may not feel it which could damage the skin.

This device will be focusing on written communication whether by typing or writing because it is a need for consumers today. In the workplace, there is a need to be able to type reports, send emails, sign documents, and other tasks involving written word. Individuals with cervical spinal cord injury do not have the ability to easily type or write without assistance because their hand cannot act in the normal manner. For a normal typing motion, the individual must have control of their fingers to extend and flex them as well as to move their entire hand over as needed to reach other keys. The device will work to encourage movement of these muscles while providing stability. By using the muscles and encouraging this movement, the consumer could partially regain function in that hand. There are some devices currently on the market, but they are ineffective as they require assistance, fall apart easily, or only address one of writing or typing, but not both. When designing the device, factors such as tenodesis and perception of touch need to be incorporated in the design to make the device accessible across different wrist positions throughout the task required and making the device comfortable for the user who may not be able to feel the texture or other components of the device (Shepherd Center 2011). Written communication is necessary to function in the workplace and the current devices do not meet the needs of this consumer group.

1.2.2 Assistive Device Background

1.2.2.1 Need and Purpose

There is a need for a better device to assist the 12,000 individuals with spinal cord injury in the United States each year to be able to more effectively fulfill their work duties (National Spinal Cord Injury Statistical Center 2013). In today’s society, written communication is essential in the workplace. There is a need for a device that will allow a user to communicate through written means such as typing on a keyboard and writing with a pen or pencil. In a study conducted by the National Spinal Cord Injury Statistical Center (NSCISC), it was found that one year post-injury, only 11.8% of people with cervical spinal cord injuries were employed and after 20 years that number rose to 34.9% (National Spinal Cord Injury Statistical Center 2013). Being able to type and write is essential in almost any workplace today. Giving the people the ability to type and write more efficiently could allow them to increase their efficiency at work and be able to secure a steady job. While some individuals can use voice commands to type, others cannot implement this system in their work environment. Being able to type and write allows them to continue their productivity. The new device will allow the consumer to type and write more quickly and require less outside assistance to put on the device compared to current methods. These improvements will make the user more efficient in the workplace and at home. They will be able to type up proposals, respond to emails, research solutions, and write letters more quickly which allows them to compete with their coworkers in terms of productivity. Approximately half of the cervical spinal cord injured patients the team interviewed expressed an importance in typing and writing in their daily lives and would like to see improvement in such devices. The other half had more recent injuries and so they were struggling with many tasks and felt any assistance would be beneficial.

There are devices on the market currently, but they lack certain capabilities that are beneficial to the consumer. Decreasing time to equip the device for use as well as the comfort level are important to try to increase the use. The main goal for typing and writing in the device is increased speed. Typing speed will be improved by creating an ergonomic design that avoids user fatigue and allows the user to maintain a typing pace over a longer period of time. For writing with a pen or pencil, the goal will be to have a device that allows the user to write more efficiently and without assistance. By having a single device that combines both typing and writing, the overall speed and efficiency will also be improved by not having to switch out assistive devices when switching between typing and handwriting.

1.2.2.2 Scope

The new device will be used by people with a cervical spinal cord injury who have function of their shoulder and elbow, but have limited mobility in their wrist and fingers. It may also be possible to be used by individuals that present with similar limited hand function stemming from other injury types such as stroke, ALS, cerebral palsy, and neuropathy. This is not the target group, but would be a benefit if it can be applied more universally to other patient populations. People with these injuries often have difficulty eating, writing, typing, drinking, and performing other daily tasks. This device will address writing and typing. It will not directly address other tasks, but there are many products on the market for eating, drinking, and other everyday tasks.

1.2.2.3 Similar Devices

There are a number of assistive devices commercially available that are tailored for those with limited hand and arm function. In particular, the Universal Cuff (Figure 3) with a dycem non-skid strap is one of the cheapest at $15, most common devices currently on the market for consumers with spinal cord injuries (North Coast Medical Inc. 2014, Patterson Medical Holdings, Inc. 2014). This device is primarily used to stabilize grooming items such as brushes, razors, or electric toothbrushes. The device is very easy to strap on as well as easy to remove.

Figure 3: Universal Cuff (Cisler 2014)

There are also a few limitations with this device. The Universal Cuff is only able to stabilize medium-sized grooming items such as those listed above. It is unable, however, to handle very small objects such as cotton swabs, regular toothbrushes, combs, pens, and pencils. In addition, the device has difficulty stabilizing larger objects or those with uneven weight distributions. The device is mostly limited to grooming items that only require a weak to moderate grip on the object (Cisler 2014).  The Universal Cuff does not provide a solution to make typing easier or more efficient for the user. This is a major problem with the Universal Cuff because it does not address this area of need.

Another device available to consumers is the typing aid (Cisler 2014), which can easily be slipped onto the hand as seen in Figure 4. A stylus is attached to the device so the user can move their whole hand and not have to worry about moving just their fingers. The limitation on this device is still that the keys must be found individually and typically only one hand is used. Due to the angle of the device, there is limited visibility of the keyboard. This increases the time required to type because the consumer cannot see the keys easily. This causes typing to be a very long, inefficient process.

Figure 4: Typing Aid (Cisler 2014)

For writing with a pen, there are many different grips used. One of the common grips is the three-jaw chuck or tripod grip, which utilizes the thumb and first two fingers (Phillips 2013). This requires the muscles to be able to hold the pen upright and then for the fingers to control the pen while it moves (OT Plan 2014). For writing with a pen or pencil, there are makeshift devices that try to keep the tripod grip position as seen in Figure 5 below. This grip holds their writing utensil in the proper position so that their muscles are supported. The limitation to this device is that it is difficult to put on. Many consumers have to have assistance with putting their fingers in the device before they use it. A summary of the benefits and disadvantages of these current devices can be found in Table 1.

Figure 5: Figure 8 Grip for Tripod Hold (Cisler 2014)

Table 1: Pros and Cons of Current Devices

1.2.2.3 Relevant Patents

There are many patents out there for splints (Patent No. 7762970, Patent No. D643931, Patent No. 8516612, Patent No. D617464) that stabilize the forearm, but these are not effective in helping written communication specifically (Figure 6).  These splints stabilize various sections of the arm including the entire wrist, the thumb only, one finger only, or some combination of these.  Some are more designed for injury, cooking, or support and not specifically communication.  Since many of the current solutions for writing and typing are makeshift, they do not have fully flushed-out patents filed.  The lack of available patents for performing both writing and typing efficiently shows a clear need for such a device to be designed.

Figure 6: Patents Available for Hand Splints (Patent No. 7762970, Patent No. D643931, Patent No. 8516612, Patent No. D617464)

1.2.3 The New Assistive Device

1.2.3.1 Objectives

The proposed device design has several objectives.  The device will be affordable so that many people with spinal cord injuries can afford it and does not add a financial burden to their life. Next, the device will be assistive in nature in order to help in written communication (writing and typing). The consumer should be able to use the device independently and take it on and off independently which is encompassed in the objective of independent usage. The next objective is it will be ergonomic in that it will be lightweight, safe, small, and comfortable to wear. The device will be lightweight so as to not overburden the user’s arms, safe for the consumer to use without fear of injury, small so it is portable and not cumbersome, and comfortable so that it does not cause chafing or pressure sores to form as a result of extended wear time. This encompasses the idea that the device should not hinder the user in any way.  Furthermore, the device will be durable and long lasting so that the consumer does not need to purchase a new device frequently. Finally, the device will be universal, or compatible, for different users within a range of hand sizes, position, or functionality (tight vs. flaccid hand).

Table 2: Objectives Pairwise Comparison Chart

The pair wise was used to compare each objective to all other objectives. The objective on the left is compared with each objective along the top. If the objective on the left is determined to be more important to device success than the one on the top, a 1 is placed in the box. If the top is more important, then a 0 is placed in the box. This is done for each objective and the total for each row is added up. The highest total means that is the most important objective to consider when designing the device. The pair wise comparison chart reveals that the device’s ability to assist a user is the most important objective, followed by ergonomics, universality, durability, independence of use, and affordability. If the device is not assisting in writing and typing, it is useless to use during those activities. This is the primary objective that must be achieved with the new device design. If the device does not assist the consumer in some way, it is not a successful device. The next most important objective is ergonomics because the way that existing devices feel during use was a major complaint of the consumers interviewed.  If the device did not feel comfortable, light, small, and safe, the patient quickly decided to use a different device to meet their needs. The device needs to be comfortable to use. This will be one of the most important objectives during development.

After ergonomics, objectives that have the next greatest importance are universality and durability.  To an extent, the device must be adjustable or have different models to manufacture in order to accommodate a wide range of hand sizes, as well as hands that are either typically flaccid or typically tight. The device must be durable because it is inconvenient to ask consumers to purchase a new one due to broken parts. While the ability of the device to be put on and taken off by the user without assistance is important, users tend to have other people around them in the workplace or at home who assist them with other tasks and these individuals could also assist in putting on and removing the device. It would be most beneficial if putting the device on and taking it off could be accomplished independently, but it is not mandatory.  Similarly, the device must be affordable within a reasonable price range, but the other objectives listed are more important to focus on.

1.2.3.2 Constraints

The constraints of the device are implemented to cover a wide range of requirements and to meet the objectives of the device.  First, the device will weigh less than a standard arm cast to limit the physical effort required to operate the device and to cut down on the cost of materials required to manufacture it.  For similar reasons, the device will be small and sleek, conforming to the arm, wrist, and hand of the user.  The device must also be smaller than a typical wrist cast.  This is a means to cut down on cost and weight, but also enable better upper limb mobility and comfort.  The device will have assistive features to enable use of teeth and elbows in addition to hands to put the device on and take it off in 30 seconds or less. The device will be inexpensive, costing less than $100 to the consumer. As this device would make their life considerably easier, the device should be affordable for people to use. Finally, the device must be adaptable enough to fit many hand sizes and degrees of functionality, so several different users of differing size and ability will test the device out to determine if this constraint has been met. The size of the device should accommodate differences in hand size for the 5th percentile to the 95th percentile of hand sizes, ranging from a palm width of 78 mm – 95 mm and a hand height of 173 mm – 209 mm (Georgia Institute of Technology 2007).

1.2.3.3 Motivation for Device

There are 12,000 new cases of cervical spinal cord injury in the United States every year (National Spinal Cord Injury Statistical Center 2013), which is a large group that cannot perform tasks efficiently. In the workplace, their efficiency is reduced because they cannot type as fast as their co-workers. This means they will take longer to type up proposals, respond to emails, and research solutions. Likewise, the inefficiency associated with writing with a pen causes this task to become essentially extinct in the life of a person with a cervical spinal cord injury. Outside of writing an occasional check or signing a form, these consumers do not write because it is too time consuming and energy intensive to grip the pen even with a device to help. If these tasks were easier and more efficient, these people would be able to perform tasks more quickly increasing their productivity.

While some similar medical assistive devices exist for people with these specific needs, it is obvious that new designs with added functional capabilities are needed. If both tasks could be performed with the same device that would reduce time needed to switch devices thereby decreasing frustration and the need for assistance. The ability to perform simple tasks efficiently and with relative ease, such as typing and writing, can drastically improve the day-to-day lives of these people.

These devices will be easy to equip and use, increasing the motivation for the consumer to make use of the device.  This is a key factor in making the medical assistive device a success. If the struggle to equip the device is more frustrating than performing the task without it, then the device will hardly be used.  Another important factor of this device is it will encourage the user to utilize both hands instead of just the one they have better control over.  This will help to curb atrophy of the unused hand.

Chapter 2

2.1 Engineering Functions

This chapter will discuss the functions that the new device must have. These will include the mandatory functions for this device to be considered clinically relevant and the optional functions which will give added benefit to the device, but are not mandatory for the overall relevance of the device. The standards that must be considered will also be discussed. There will be a variety of stakeholders and users of the device which will be listed and discussed here.

2.1.1 Mandatory Functions

There are a number of mandatory functions the device must have to be successful. First of all, the device must improve typing words per minute by 20% as well as reduce errors by 10%. Currently, people with this disability experience difficulty typing quickly and efficiently due to limited fine motor control. This device will allow them to increase both the speed of typing as well as accuracy and efficiency. The same is true for handwriting. The device will also help increase the speed and accuracy of handwriting. The device will increase the hand-written words per minute by 20% and also improve readability and handwriting. All of these percentages will be the device compared to the consumer’s current method of writing. In addition, the device must encourage users to utilize both hands equally. This will allow for improved dexterity and strength for the non-dominant hand while typing as well as performing other tasks.

The device also must take less than 30 seconds to put on and must not require assistance from another person. Many consumers use their teeth to assist them in putting devices on and getting them off. This must be considered when designing the device and the ease of getting on and off. Additionally, the device will allow the user to use a mouse or touchpad while typing. It is common practice to type and navigate the screen with a mouse or touchpad simultaneously, and this ability must not be hindered. Finally, the device should be smooth and avoid rough edges. Many of the consumers have decreased sensation and would not be able to feel any protrusions on the device. As such, if there is a rough edge, it could be harming the consumer unknowingly. A summary of the functions that are mandatory for the device can be seen in Figure 7 as well as the requirement to check the function and how that test will occur.

Figure 7: Mandatory Function Tree

2.1.2 Optional Functions

The main optional function is that the device should not look like a medical machine. The device should maintain normal looking aesthetics as much as possible. The consumers often have to deal with the psychological effect of doing something differently due to having a device. This can be limited by creating a device that has natural appearing function and is the proper size and shape to what would be performed by an uninjured person. If the device is inconspicous, that aids in use because observers do not notice a difference between what the user is doing and what is normal. An example of this restoring function and keeping the function looking normal is Dining with Dignity as shown in Figure 8 (Dining with Dignity 2014).

Figure 8: Dining with Dignity (Dining with Dignity 2014)

Dining with Dignity allows the consumer to slip their hands into the device easily and then bring the food up to their mouth the same as anyone else would bring food to their mouth. The device will look as similar as possible to an unmodified device.  People with spinal cord injuries tend to favor devices that do not look too different from the devices they utilized before their injury.  The device must look very similar to unmodified devices, so as little aesthetic differences must be visible as possible.  This means that color, texture, and shape must be closely matched between modified and unmodified devices.

Likewise, the device should encourage the use of both hands and mimic the normal motion. Devices are more useful and more used according to interviews with potential consumers if they promote normal use. For example, with writing with a pen, being able to use a normal grip is more favorable to wrapping the entire hand around the pen and writing vertically with that.

It would also be beneficial if it helps with other tasks or populations. People with cervical spinal cord injuries have difficulty with many tasks, not just written communication. If the device could also help with these other tasks that would be an added benefit that would make the device more clinically relevant than it already is. There are other injuries that present with similar symptoms to cervical spinal cord injuries such as stroke, neuropathy, and ALS. If the device were able to help these other patient populations, that would also be an added benefit.

2.2 Standards

When designing this device, some of the main standards that must be considered come from ANSI, AAMI, and ISO.  The main areas that are standardized include human factors, health safety, design process, preferred practices, and risk management.  The following standards are applicable to this design.

ANSI/AAMI HE48: 1993 refers to human factors engineering guidelines and preferred practices for the design of medical devices (ANSI/AAMI (n.d.[a]).  ANSI/AAMI HE74: 2001 refers to human factors design process for medical devices (ANSI).  AAMI HE75: 2009 refers to human factor engineering-design of medical devices (ANSI/AAMI (n.d.[b])).  ISO 14971:2007 refers to medical devices-application of risk management to medical devices (ISO 2007).  ISO 10993-1:2009 refers to biological evaluation of medical devices (ISO 2009).  This is especially important, as the user will most likely be using their mouth to aid in the equipping of the device.

With these standards in mind, it is important to adhere to them when designing the device.  As long as all the required standards are met, the device would be able to go into the market very soon granted it makes it to that stage of development.

2.3 Stakeholders and Users

The user groups for this device are anyone with little to no fine motion control with their hands. The main focus group is consumers with cervical spinal cord injury; however, the device could likely be easily used in other injury fields such as stroke, ALS, or neuropathy. Those populations will not be the main focus of this study, but could also potentially benefit. These devices would help them perform daily activities without relying on help from someone else.  Going past the people with disabilities using the device, it would also have an impact on the potential employers of these consumers.  With most jobs in today’s society, typing on the computer and writing are almost always a required skill.  With the help of this device, the typing and writing speed of the consumer would increase, thus making them able to perform at their job more effectively. The device is also beneficial to aids and family members of those that have a spinal cord injury. If the task is easier to perform, the consumer would not need as much assistance from the aid or family member, allowing those groups more time to work on other tasks.

2.4 Sustainability

Ideally, this product should last somewhere around 5-10 years.  Due to the simple nature of the design and how it will be handled on a day-to-day basis, there should not be significant effects of wear and tear.  The forces associated with using the device is also very small, making the durability goals much easier to achieve.  As most people use their mouths extensively in order to assist with equipping the device, the material should be safe to use in regards to this.  Because there is not extensive durability issues, the material will be more focused on comfort and fitting the hands snuggly.

In the long term, once the device is ready to be thrown away, the best-case scenario would be for the device to be fully recyclable.  Due to the limitations this might cause with the design, the goal will be to make as many of the different materials environmentally friendly, minimizing the effects of pollution when sitting in a landfill.  This goal should be a priority.

Chapter 3

3.1 Concept Selection

This chapter will describe the process of concept generation and modification. The top several devices will be described in detail including mock-up pictures of the devices. The final selection process will be described and validated before describing the final device design.

3.1.1 Development of Initial Concepts

During consumer interviews, ideas on device concepts were discussed between the team members and the patients.  Every interview yielded a different perspective on how current devices could be improved or re-imagined in order to better fit the needs of the user. Before committing ideas to paper, the team examined the current market of written communication assist devices and weighed each existing devices’ pros and cons.  Some devices were more ergonomic and some had better functionality, but none of the devices struck a good balance of both attributes.  Additionally, many of the better devices examined were just prototype models that had never been mass-produced and put to market.

After bouncing ideas around throughout several weeks, the team met together and brainstormed the vision of the device.  The main focus areas were that the device concepts must allow the user to write and type more efficiently, they needed to be as ergonomic as possible to improve comfort, and they needed to be achievable within the means of the project.  Each team member separately free sketched 20 concept designs on paper.  Some of these designs were entire devices, while others focused in on one feature or one area of the potential device.

Each sketch was not required to cover the functionality of both writing and typing.  Some concepts, for example, showed how erasing could be achieved with minimal effort, how a stylus could be incorporated that can interact with touchscreen devices, and how wrist cock-ups or splints could be incorporated to decrease fatigue and direct a more natural writing/typing hand position.  Some concepts involved intricate mechanisms for writing utensil attachment, while others contained more elegant designs that require less materials and reduced the manufacturing complexity.  There were even some similarities in design that emerged between team members that could be combined to produce even more refined conceptual ideas.  Overall, the team was satisfied with the breadth and depth of ideas they had created and how they may be combined to create mock-ups to present to patients.  Figure 9 shows a couple examples of concept design sketches.

Figure 9: Sample Concept Design Sketches

Figure 10 shows options of how different aspects of the device could be accomplished based off the many ideas presented by the team.

Figure 10: Concept Tree

3.1.2 Concept Screening

For the initial idea generation process, each team member was required to brainstorm and come up with 20 design sketches for a total of 100 sketches for the team that contained 5 members. These design sketches were to contain any ideas that could be implemented in the docking station device and didn’t have to be complete designs for device. Each sketch was explained by its owner in a group meeting to familiarize everyone with all the concept sketches created.

From here, all of the sketches were passed around the table to each group member and if an idea was liked, it was placed in the middle of the table to be examined further. Those designs not placed in the middle of the table did not strike great interest by the group and thus were not to be considered further in the screening process. This first phase narrowed the sketches down to around 35. To make this number more manageable, ideas that were duplicated were removed. Also sketches with similar functions were combined into 1 single sketch idea. These two processes of deleting duplicates and combining similar functions resulted in 25 total sketch ideas. These 25 final sketches were then categorized into 3 groups based on function: typing, writing, and combined typing and writing design ideas.

The group then explained each concept remaining to the group again and there was open discussion on the advantages and disadvantages of each concept. The group decided that a manageable number of final sketches to present to its engineering and clinical mentors was around 15 sketches. This number was decided because the group wanted to have enough sketches for the possibility of throwing out a couple based on mentor feedback, and also not having too few sketches to not allow 5 mockup prototypes to be designed later in the design process. The team also didn’t want to have more than 15 final sketches because too many sketches would take too much time to analyze and narrow down to 5 final mockups designs later in the process. Thus, from the 3 categories of typing, writing, and combined typing and writing, 5 sketches from each category were voted on during in-group discussion to complete the initial concept screening. These final designs were later presented to the engineering and clinical mentors to narrow down further into an eventual 5 mockup prototypes for the docking station device.

3.1.3 Conceptual Designs

The first alternative design was the magnetic wrist strap. This design consisted of a simple strap around the palm of the hand with a magnet attached at the center of the palm. This device would also come with small magnets that could be attached to objects such as a pen, pencil, or typing device. The magnet on the palm would then be able to pick up any object with a small magnet attached. Examples of these attachments can be found in Figure 11.

Figure 11: Magnetic Wrist Strap Device Design

This device would have the potential to assist the user beyond typing and writing. The consumer would be able to pick up other objects such as phones, television remotes, or silverware by attaching magnets to these objects. However, patients are very wary of regularly handling magnets for fear of affecting credit cards, phones, or computers. In addition, the user of this device would not be able to write in a typical writing fashion, but instead would have to grip large writing utensils with the palm of their hand.

The second device consisted of a handle on which to place the palm, and a strap around the back of the hand. The device would also have two removable prongs protruding from the front of the device to assist with typing. A slot for a writing utensil would be located near the inside of the hand between the thumb and index finger. The consumer would use one device with the writing attachment on their dominant hand, and one without the writing attachment on their non-dominant hand.  A mock-up of this device can be seen in Figure 12.

Figure 12: Wolverine Device Design

This device would allow the consumer to type much faster with four total prongs to use for typing. This device would also have the potential for other attachments. However, the device would take a significant amount of energy to rotate the arm to control the prongs on each hand. The device also contains many parts and may not last as long as a device with only one piece.

The third device was a plastic piece with two holes: one for the index finger and one for the middle finger. The device would also have a slot to insert a writing utensil. A mock-up of this design can be seen in Figure 13. This device would allow the user to write with a technique close to typical writing. The device would also be small and inconspicuous to help with aesthetics. However, this device does not assist the user with typing. In addition, the device only supports two fingers. Consumers with flaccid hands would not have support for the rest of the fingers to restrict their motion.

Figure 13: Dinning with Dignity Device Design

The final alternative design was a hybrid between the second and third device. This device consists of a handle on which to place the palm, and a strap around the back of the hand. The device would also contain a hole on the inside of the device to support the thumb. The handle and strap would be adjustable to fit a variety of hand sizes. An eraser would also be located on the outside of the device for easy erasing and typing assistance. A mock-up of this device can be seen in Figure 14.  This device would provide enough support for both tight and flaccid hands. However, it would be difficult to design an attachment for the writing device. In addition, the device does not significantly improve typing.

Figure 14: Hybrid Device Design

3.1.4 Selection Process

The table below (Table 3) shows the quantification of Team Jomokedalexenn’s decision matrix for choosing the final device. Each criterion was given a certain weight with six meaning it is the most important and one meaning it is the least important. Each design was then evaluated on those criteria and given a ranking of one through five with five meaning it was very good at fulfilling that requirement and one meaning it was very bad at fulfilling that requirement. The weight is multiplied by the rank, which gives a product. These are added up for each design to find the total. The largest total was then selected as the final device design.

Table 3: Final Design Decision Matrix

The criteria used to determine which device was the best were the objectives: affordable, assistive in nature, independent usage, ergonomic (safe, comfortable, light weight, small), durable, and universal. The weight on each of these was based off of the pairwise comparison chart (Table 2). Assistive in nature was the most important objective because it is the entire purpose of the device so it was given a weight of 6. The next most important objective was ergonomic. Ergonomic encompasses the safety of the device and comfort of use so it was given a weight of 5 as the second most important objective. The consumers interviewed described their lack of desire to use devices because using the device tired them out. The third objective was universal. The device needs to be able to be used on individuals of varying hand sizes and levels of function so it was given a weight of 4. It is not the most important because it would still be helping someone, but it is better if a wider audience can use it. The device must be able to last for several years without breaking so it was given a weight of 3. Some of the devices today are not durable and consumers complain of having to purchase a new one every couple of years. The device should be able to be used for longer than the current devices, but if it works well, it would still function. The device will be most useful if the consumer has the ability to put it on by themselves and does not need assistance from another individual to use it properly, but the device will still work if someone has to help the consumer put it on so independent usage was given a weight of 2. Many consumers have help and are used to it, so it is not of the most importance that they be able to use it independently. Finally, the device would be most useful if it is affordable, but is not mandatory so it was given the lowest weight of 1.

The products evaluated were the magnetic wrist strap (Figure 11), the simple dining with dignity idea (Figure 12), the wolverine (Figure 13), and the hybrid (Figure 14). The values were assigned based on the projected results of each device from consumer feedback, current device similarities, and other research. The devices were also compared to each other so that devices that were comparable could be given the same value.

For the magnetic wrist strap, the magnets would make the device more expensive to produce, which would increase the cost to the consumer. It still would not be outrageously expensive, but it would be more expensive so it was given a rank of two. It is quite assistive as it can work for typing and writing and with the magnets could potentially have other functionalities added which would make it better than others. It would however, have potentially the same problems with typing that some of the current devices have so it was given a rank of four. For independent usage, the magnets allow for the consumer to have a station to hold the attachments which would allow them to get them off and on easily on their own, giving a ranking of five. Ergonomically there are some concerns about magnets and their proximity to electronics, which could cause problems. Due to the magnets it would also be a bit heavier so it was given a ranking of three. It would be very durable, but the magnets may age which would decrease durability so it was given a rank of four. Finally, it is universal because the strap could be designed to easily fit a variety of hand sizes so it was given a rank of five for a total of 83.

For Dining with Dignity, very little material would have to be used because it is so small and lightweight. This would make it very affordable and also very ergonomic giving a rank of five in both of those categories. It would, however, have problems with being assistive in nature because it was only designed to help with writing, not typing. This means it should be a rank two for assistive in nature. It would be easy to slip on and off independently, giving it a five ranking and would be durable because the material would be solid and strong giving a five in the durable category. For being universal, this device is not the best because there are different finger sizes and strengths. With tenodesis and flaccid hands to account for, this device is complicated because the consumer may need somewhere to place the other fingers if they have a flaccid hand and the tight hand may cause discomfort due to the positioning of the fingers so this was given a rank of three for a total of 79.

For the wolverine, the prongs would have some kind of hinge or method to control whether or not the prongs are out which means there would be more parts to pay for and it would also mean that there are more places where the device could potentially fail meaning it would be less durable. This results in a two ranking for both affordability and durability. The parts increase failure points and also increase the cost to manufacture. It is assistive since there is the potential for pencils to be put in as well as the typing aids. It would be difficult with typing and how that would go in or out so it was given a four ranking. With a strap, it might be a bit more difficult to place on the hand independently with the typing aids to also have to work around so that was given a ranking of three. With more parts, it is also less comfortable and has the potential for things to break, which makes it less safe. It would also be taxing for the user, as they have to move their hand in a less favorable way energetically. This was then given a ranking of two. Finally, the strap could be made to fit many hand sizes, but it also may require more tightening and adjustment so it was given a ranking of three for a total of 60.

For the hybrid design, there are multiple facets to the device and some adjustments that the consumer would be able to make so it makes it a little bit more expensive, but most of the materials are inexpensive so affordability was given a four. This device is very assistive in nature as it has the ability to write and type and erase so it was given a ranking of five. It combines similar devices on the market and improves upon them to create a better hybrid approach. There may be minor adjustments that need to be made by the user, but overall it should be easy to slip on and off independently so that was given a rank of four. Due to the multiple components, there is a chance it will be a bit bulkier so ergonomics was given a rank of four. The telescope feature will make it smaller when needed which is why it was not ranked even lower. With multiple components, there is also more chance for failure, which gave this ranking a three for durability. The bar will be adjustable in length to allow for stylus use so the universal component is built in to the device, but the upper strap may need adjusted giving universal a ranking of four for this device which results in a total of 87.

To look at the numbers comparatively, for affordability the dining with dignity is small and cheap material while the hybrid is still inexpensive material, but has slightly more. The magnetic wrist strap and wolverine have more components and they are more expensive components, which results in the significant drop to two. For assistive, the hybrid was the one the consumers liked the best and felt would be the most useful. The magnetic and wolverine both have the ability for both writing and typing, but do not necessarily have the best method of doing that. The dining with dignity is much lower because it only has the one function. For independent usage, the magnet gives the user the most independence with the magnetic holder as does dining with dignity because they can slip it on alone. The hybrid is an easier handle to slip on, but may have issues with the pencil. Wolverine is just slightly lower because there may be issues with slipping on around the stylus. For ergonomics, the dining with dignity again is safe and small because it is a small device and would be one piece. The hybrid is next because it mimics what many consumers do now with or without devices, but is a little bit bigger. The magnetic wrist strap gets heavier because of the use of magnets. Finally is wolverine being lowest because there are so many parts and the wrist rotation required to use the stylus would be hard on the muscles. For durability, dining with dignity as one piece is the best at five. The hybrid is close behind because it will have some parts that move, but will be made of sturdy materials. The magnetic wrist strap is next, but due to the magnets being a part, the wear and tear will be different on that device, decreasing the durability. Finally is wolverine because the parts are smaller and there are quite a few which allows for the possibility of something breaking. Finally is universality, with the magnetic wrist strap being the best because it is easy for people with a flaccid hand to wrap around or a tight hand to grip. Next is the hybrid because the strap will need adjusting each time and may take more time. The dining with dignity and wolverine are on the same level because dining with dignity may be a problem for those with a flaccid hand not having anywhere to put their other fingers and the wolverine will have a strap that needs adjusted and the bar may also be too long or too short depending on the person. It is hard to adjust that length because the stylus is in place there as well.

After this decision matrix, the device that was selected was the new dining with dignity. There were a few modifications discussed to this device throughout the decision matrix, which were added to the final device design.

3.1.5 Description of Final Proposed Design

As stated before, the device selected through the decision process was the hybrid.  This design exemplified all of our required objectives the best.  The hybrid design will be our guide model for any future modifications that we may make as we progress through the design process.

The main features of this device allow the consumer to write, erase, and type more efficiently.  To put on the device, there is an adjustable Velcro strap that the consumer can easily slide their four digits through while at the same time being able to fit any user.  The thumb has a separate half tube slot, attached to the main handle, for the purpose of shaping the hand into a more natural writing position shape. To connect the half tube, there is an elastic band connected across the diameter in order to hold any size thumb snugly against the tube.

The Velcro strap is then attached to a 1″ diameter handle for the purpose of giving the consumer something to grasp along with supporting their hands and fingers.  This handle features a “telescoping” function, allowing the consumer to choose the length that they would like the handle to be.  This allows for a great diversity in the overall shape and functionality of the device.

Placed at the pinky end of the handle, there is a stylus extruding 3/4”, which allows the consumer to simply pronate their arms into pinky down position and press keyboard keys.  This stylus will work with a laptop touch pad as well.  There is also an eraser attachment that will be able to replace the stylus, allowing the consumer to choose which insert they would like to have attached.  This will allow the consumer to erase in the same way that they would use the stylus.  To accommodate the writing utensil, there is a hole between the thumb and index finger, which will hold the writing utensil securely in place.  The writing utensil slot is positioned in this manner to allow for a more natural writing position.  It is also mimicked on the second handle in order to accommodate both right and left-handed consumers.  To further aid the ease of writing, the material used on the downward facing side of the handle is a very smooth material, which will allow the consumer to easily move their hand across the writing surface.

A SolidWorks model of the device, including all of the previously mentioned elements is shown below in Figure 15.

Figure 15: SolidWorks Model (Isometric View)

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