Embedded Files
Below, you can see a CAD image of the overall current design.
Inner Wheel
The inner wheel is the part of the design that holds all of the inner components that rotate. As the hair rotates with the system in a counter-clockwise motion, the wheel helps the tape wrap around the hair, which also tightens the tape. The user can choose however many wraps they want to do depending on how tight they want the bundle, and when they are finished, they remove the hair from the inner wheel and proceed to cut the tape.
Wheel Stopper
The wheel stopper keeps the wheel from rotating. The stopper consists of a toggle that is attached to a spring inside the housing of the grip. When the device is used, the toggle is pushed down, freeing the wheel from being locked in place. Once the user is satisfied with how secure the hair is, the toggle is then released and once the current revolution is finished, the stopper will re-enter the wheel, produce a clicking sound to confirm that it is locked in place, and prevent the wheel from moving. Keeping the wheel in place in the initial position helps the user grab the tape and wrap the targeted area with the hand that is not holding the product. It also assists the user in cutting the tape because it keeps the tape from rotating along with the cutting motion performed by the user. Another purpose of the wheel stopper system is to force the user to hold the product in a “precision grip”(6), so that the user has better control of the product. In addition to that, it is a more comfortable and controllable grip than the traditional grip of wrapping the whole hand around the handle at different angles, especially at the angle of intended use which is parallel to the ground.
Tape Guide
The tape guide is the area where the hair is housed during the rotation. The tape is wrapped inside the top of the tape guide, where the adhesive side faces upwards. On the left side of the magnified image is where the blade is housed. This extension allows the tape to lay inside of it when it is not in use. When the tape is held with the bundle for the half of the first rotation, it was demonstrated that the bundle would succeed in every trial. However, if the tape was not held to the hair and did not stick within half of the first rotation, the bundle could fail to be created. This part of the product allows for a significant length of the tape to be more exposed so that the user could more easily grab the tape and hold it to the hair that is being bundled. In addition to assisting with the initial bundle the extension holds the tape securely and helps the product be used in a variety of positions, rather than just vertically. If it were not there, the tape would flop onto its side when the product is held horizontally, making it more difficult for it to be controlled and grabbed by the user.
Tape Cutter Blade
The tape cutter is housed in the tape guide area and is required to be sharp enough to cut the tape being used. Because a saw-type blade has been chosen, the cutting force is distributed along a longer length than with a single point blade and can more easily cut the tapes being used with the device.
Tape
The tape’s adhesive needs to be water resistant with a strong hold so that the bundle does not slip or become undone during a surgical operation (at least 2 hours). It may soak up bodily fluids during the operation, so it must be resilient enough to maintain its hold with the added weight. For surgery, it is recommended that surgical tape is used for the bundles. For other applications, the chosen tape may be anything that is able to be cut by the saw-type blade. Plastic-type tapes, like electrical tape, may be too elastic to properly be cut by the blade. In addition to strength, the tape must be easily able to be pulled from the tape holder, because the resistance at this stage adds to the force on the hair while it is being bundled. This property can be seen in the tape by how well it sticks to itself. For example, electric tape has a strong hold on itself, while surgical tape does not, which is another reason that surgical tape is recommended for the intended use.
Bundling Analysis
The first analysis that was performed was to measure how well the product could create tight bundles of hair. The product was tested to see at what rate it could reduce the diameter of grouped strands of hair.
The results of this test showed that the product could reduce the diameter of the grouped strands of hair by 80%. The diameter of the hair strands increased from 4cm at the target area to 0.8cm. In addition, multiple bundles of hair were then bundled together in order to secure them from freely moving around. This test also simulates the act of folding a bundle of long hair to create a shorter bundle of hair that is more controllable for the surgeon.
Two Individual Bundles One Bundle
This test validated the general use of our product and illustrated that it will be able to create tight bundles of hair
Duration & Resilience Analysis
One of the most important aspects of the product is the duration that the tape will hold and its resilience against the absorption and presence of bodily fluids during surgery. This has more to do with the material properties of the tape than the product itself. The types of tape that were tested are surgical tape, electrical tape, and waterproof scotch tape. First, bundles of hair using the product were created with each type of tape. Next, the bundles were gently scrubbed using sponges soaked in room temperature water to simulate the sterilization process, where betadine sponges are used to sterilize the patient’s head. Every 5 minutes for the next hour, each sample was submerged in the water to simulate a flow of blood to the taped area. The results of these tests showed that each type of tape was able to withstand the surgical conditions. Due to the tightness of the bundles, there was not a significant amount of surface area in which the fluids could enter and disrupt the hold of the adhesive. From these results, it can be concluded that the type of tape used for surgical purposes can be decided by the user from the three options. It is recommended that surgical tape is used because that is what surgeons are already familiar with in the operating room, and it is also already approved for medical use.
Something critical that we learned during one of the trials is that the tape loop must be closed before fluid comes into contact with the bundles. If the end of the tape loop is not pressed down, then fluid can come into contact with that adhesive. As more fluid is introduced to this weakened section of the tape, the tape can unravel and more adhesive will be weakened. This can possibly affect too much of the tape so that the tape loop would fail. Although this may be obvious, pressing the tape down was not an explicit instruction that we kept in mind, so we incorporated it as a final step in the user manual to be sure that the tape loops will be secure. Below, you can see the issue and how the tape loop began to unravel.
Speed Analysis
The speed of the product was compared to the conventional method of taping hair in the operating room. To test this, the product was used on a real person’s hair to see how fast it was able to bundle the hair. This test took 15 seconds in taping a bundle of hair, while the conventional method took 32 seconds, illustrating that the product reduces the time to bundle the hair by 54%. In addition to saving time, it eliminates the use of an assistant nurse to tape the hair, therefore saving cost and making the whole preparation process more efficient. Below, you can see the current convention on the left, versus the engineering team's prototype on the right.
Current Convention Engineering Prototype
Page updated
Report abuse