e-NABLE Design Briefs for Autodesk University
Challenge One: A Fitting SolutionFunctional Thumb and Residual Fingers
Current designs are not well suited to recipients who have residual fingers and or functional thumbs. The Matching Team have identified two common configurations. At present, recipients with these anatomies are not well served by the devices currently available. Design a NEW hand or modify an existing hand to address the specific needs of this population.
Anatomical variant: recipient has a functional thumb with residual fingers.
The problem: There have been several attempts address the needs of people with this anatomical variation. Two designs for individuals with functional thumbs currently being produced, a thumbless version of the Raptor Reloaded and a thumbless version of the Cyborg Beast. The Thumbless Raptor Reloaded is problematic due to the unnatural and inconvenient placement of the thumb which results in restricted movement. The design of the Thumbless Cyborg Beast generally is somewhat more successful than the Thumbless Raptor Reload, but there are still limitations in the design.
The design modification to the original Cyborg Beast design address the mobility issue by removing the entire side of the device. This frees the thumb but still results in problems with grip due to the incorrect proportion of the device fingers to the recipient’s thumb as evidenced in these photos:
Cyborg Beast Thumbless option
Thumbless Raptor Reloaded
Notes and considerations:
Benefits of the Cyborg Beast Design:
- One hinge design of the cyborg beast allows for freedom of movement of the residual thumb.
Cons of the Cyborg Beast Design:
- Due to the need of the extended hinge(allows for correct placement of the hinge on the wrist, while compensating for residual fingers), the device becomes exceptionally long (see photos below) which does not allow for a natural grasping motion due to the difference in size between the natural thumb and the device fingers.
- One hinge design is more delicate causing more instances of device failure due to the hinge breaking when bent without support of the wrist.
- Recipient must place natural hand in the device in an unnatural position to insure fit. This leads to a less comfortable wear experience which in turn results in less frequent usage.
- Device finger placement creates an unnatural grasping motion that makes it difficult to pick up items without assistance from the unaffected hand.
Desired outcome: Comfortable proportionate device with a more natural grasping motion that allows for use of the recipient’s thumb.
Challenge Two: A Fitting SolutionResidual Fingers
Current designs are not well suited to recipients who have residual fingers. The Matching Team has identified two common configurations. At present, recipients with these anatomies are not well served by the current devices. Design a NEW hand or modify an existing hand to address the specific needs of this population.
Anatomical variant: recipient has residual fingers.
(Please note that in this photo the lower hand is the one we are designing for)
Current Design: none. The list of currently available eNable hands are not easily customizable to accommodate patients with partial fingers. The designs do not have a slot or space between the fingers were the patients can slide a partial finger into (and still have that finger be useable with the other prosthetic fingers). The knuckle pins on the existing Raptor Reloaded design, for example, would protrude into the patient’s partial finger.
Files: Raptor Reloaded (link)
Give a recipient the ability to use natural digits along with the created device to obtain a grasping motion. Possible thumb only device or a four finger device. The fingers on said device would need to be size appropriate to achieve the desired grasping motion. A parametric design in preferred so that it’s easy to accommodate varied residual finger anatomy.
Dr. Jordan Miller at Rice University had a summer fellow, Akhil Surapaneni work on this issue. Although time did not allow a full investigation of the issue, they (Dr. Miller, Akhil, and Dr. Gloria Gogola [Shriners Hospital]) theorized that a solution might involve:
- Create a hand in which the user can parametrically create a slot for the patient’s partial finger. The current Raptor Reloaded design doesn’t have a parameter that defines the width between the fingers, so a new palm might need to be designed
- Create a parametric extension for the partial finger so that the partial finger can become the same length as the other fingers. This extension should be powered with the partial finger.
There is no standard way at this time to handle this – different people have done different designs – each on customized for the recipient’s anatomy. Here one user-centered way this was handled by Enable community member Martin Van Wezel:
More information about this design here: https://www.youmagine.com/designs/e-nable-yulia-custom-hand
The goal would be to design a device that could be customized for each recipient but which builds on a common base.
Challenge Three: A Handier Hand
Background: Justin Laviguere, an undergraduate mechanical engineering student at Seattle Pacific University, conducted an ECF sponsored internship over the summer. Justin worked with Dr. Adam Arabian to address the issue of continuous grip. Enable hands close by flexing the wrist. This action is well suited to tasks that require an intermittent grasp but for tasks that require a continuous grip, such an action can be tiring, tedious, and in some cases, painful.
The internship focused on creating an interface for eNable hands that uses an attachment base which can easily be build upon to create new components based on an individual user’s specific needs or interests. Basically, the adapter allows the eNABLE hand to connect to another tool such as a broom. This allows vocational adaptation to existing eNABLE hands in order to better accommodate users who want to complete specific tasks where the eNABLE device isn’t ideal to use or is exhaustive for the activity.
Justin designed a geometric interface that can be attached onto either the right or left palm of a Raptor Reloaded or a Phoenix hand. The interface locks in place, is adjustable for position, and can be scaled as the hand is scaled. Attachment components can be designed that will lock into the interface. These components will allow the Raptor Reloaded and the Phoenix hands to do tasks they don’t currently do well adding functionality to the hands by allowing a wearer to do something they previously could not do or could only do with great effort.
Files: (http://www.thingiverse.com/thing:1066879 ) Source files are also available however, this challenge is to design a component for the published interface which has a specific octagonal geometry.
The Challenge: create attachments for the geometric interface relating to common occupations and day to day tasks for refugees would be particularly useful. Here are some jobs and attachments that could benefit with having specialized attachments:
- Seamstress – sewing/sewing machine
- Farmer – use of farm tools
- Carpenter – woodworking tools, hammer/nail placement, screw driver, saw
- Mechanic – wrenches
- Lawyer – aids with writing
- Cook – open twist containers, hold container steady, use kitchen utensils
- Hairdresser/Barber – scissors/comb/brush/clippers/vacuum/broom/spray/type
- Other useful things might be a universal/adjustable size smart-phone holder, ball grip (for sports), fishing pole grip, or something to aid with holding eating utensils.
Detail of Adapter:
Tool Adapter on a Phoenix Hand: