Arch4All: Part 1
What is the problem you’re trying to solve?
In the realm of adaptive wheelchair archery, players with limited strength and muscle mass are not physically capable of holding and drawing a bow, and there are no current affordable solutions on the market. Our goal is to increase engagement in adaptive archery and enable and improve independence by creating a device that will assist with drawback and partially support the weight of a compound bow for archers with low muscle mass and limited strength.
What steps have you taken so far to address the problem?
To address this problem, we started by creating our needs statement and coming up with our design requirements. These design requirements included independent load, draw, and fire, usability with all compound bows, increasing user’s draw weight, and, most importantly, safe, consistent, and reliable performance. Next, we spent time investigating the market to discover existing products and have looked
at both their limitations and how we might be able to use certain aspects of these existing products in our own design. So far, we have come up with initial concept designs for two different components of our solution: the drawback mechanism and the bow mounting devices.
What did you learn from the design review and how will you apply it?
By communicating our presentation with several people, including our community partner, we learned about additional products available on the market that would accomplish what we were designing. One of these products was the vertical crossbow. Since our design would essentially turn a compound bow into a crossbow, we learned from the community partner that the most comfortable position for the crank for the design would be somewhere below the handle grip. However, because of these products, we decided to move forward with a project that was more dedicated to designing a mount for the bow rather than a drawback mechanism for the bow. Meeting with our community partner for the second time with more developed research questions, we were able to learn more about the specific accommodations needed in our design. We also discussed compromised adaptations such as the community partner’s openness to develop a new sighting technique as a result of a stronger bow stabilization. Additionally, although our team was hesitant to use electronics from a safety standpoint, both our community partner and design reviewers brought up interesting ideas to convince us to continue to have an open mind about electronics. Finally, a common theme expressed during design review is the importance of meeting our community partner in person. As a result, we confirmed a good meeting location and are excited to show him our prototype in the future. We received a lot of beneficial feedback from Design Review One that allowed us to establish a clear direction and timeline in preparation for Design Review Two.
What are your goals for Design Review 2?
Our goals for design review 2 are to have some physical prototypes constructed for the community partner to try. Our stretch goals are for us to construct working prototypes for each of the bow mount
designs and each of the bracket to bow connection concepts. However, with Thanksgiving coming up we want to be respectful and mindful of each other’s time and mental health so we will not be doing any work over the thanksgiving break (the wednesday before thanksgiving or the sunday after). With these things in mind, our most realistic goals for DR2 are to have at least one working prototype for both the bow mount and the bracket to bow connection concept.
Tripod Mount Device
One of our ideas is a tripod-like device that allows our community partner to mount their bow with several degrees of freedom. The device will use both a vertical bar and a horizontal bar that the user can adjust as they aim the bow and arrow. The vertical bar will provide horizontal bow rotation, and a PVC pipe connecting the two bars will allow vertical movement of the bow. Both components will have locking mechanisms to stabilize the aim. We also intend to use a GoPro mount at the bar to serve as a connection point, allowing the bow to be tilted up and down. Additionally, there will be a hook positioned at the bottom of the device to provide stability and counter the weight of the bow.
Camera Mount Brace
This design focuses on using a camera/laptop mount to provide the user support, and multiple degrees of freedom, to aim their bow. A bracing bar provides support to the mount by attaching to the back of the wheelchair, removing load from the mount itself. The camera mount will be clamped to the arm of the wheelchair for stability, and convenient placement with respect to the user. We plan on using bar clamps to attach the brace to the chair and mount, as this method of attachment will allow for rotation of the brace forwards and backwards, which is key for the aiming process. Future design considerations will include methods of adding stability, and ensuring that the user is comfortable with the design.
Chair Mount Concept
This mechanism allows the user to adjust for bow placement to a desired location by using two sets of telescoping tubes, (colored in red and blue in the diagram below), since it allows easy adjustment of bow location and tight locking with a flip-lock. The mechanism is attached directly to the wheelchair with no modification to the wheelchair and must be structurally stable to withstand the recoil of the arrow firing. Additional braces may be required to stabilize the mechanism. Our next steps in this design is to perform initial prototyping and adjustment of design from the information we collected from the prototype.
