Golf Prosthesis Final Design Report (P3)
On April 10, 2011, our senior project team came in contact with Jim Taylor. He is a double arm amputee who was injured in a severe electrical accident on May 5, 1965, where he was shocked with 7,300 volts of electricity from a nearby power line, at the age of 10. In the accident Jim broke his back and suffered severe tissue damage causing his arms to be amputated. His left arm was amputated just below the elbow while his right arm was amputated just above the elbow. Shortly after his accident Jim Taylor picked up the game of golf, and has been playing now for the past 40+ years.
“‘The game is my therapy. It’s physical therapy and it’s good for me inside, too. It gives me a sense of accomplishment,’ said Taylor, who has undergone 20 surgeries in his lifetime, including four on his back” (The Daily News Online).
Jim is not your average golfer. Although a double arm amputee, he is amazingly talented and has 17 hole-in-ones, a 12 handicap, and an assortment of amputee golf titles to show for it.
“In so many mysterious ways, golf has helped Taylor. . . level the playing field. . . ‘If you can golf, you can just be a golfer. All handicaps are out the door,’ said Taylor” (The Daily News Online).
Jim currently lives in Washington State where his current golf set up is based around a set of custom built golf arms, which retail for about $10,000. Using his golf arms, he secures the golf club between his hooks with an interlocking grip; in the same fashion an able bodied golfer might grip a golf club, except imagine doing so using only two fingers on each hand. To achieve better control, Jim uses athletic tape, which he wraps around his hooks to increase their size, which increases the surface area contact with the golf club. This can be seen in figures 6 and 7 in the Existing Products Section of this report. He then takes further measures to ensure that the club is not lost during the golf swing by securing the butt end of the club into a C-shaped groove that is attached to his left forearm. Recently, Jim has added to his design by incorporating bungee cords, which he wraps over his hooks to increase their grip strength. Today, the golf prosthetic Jim uses is the result of 15 years of engineering, adjustments, and many iterations.
“The golf arms are equipped with heavy-duty cables for flexibility. The left arm has a C-shaped groove fastened on for the golf club to slide into. The inside of the groove has a rough surface so it’s more difficult for the club to slip.
Once the club is in position, Taylor clasps his taped hooks around the shaft and swings away. His backswing isn’t very deep, but his leg push and timing are near-perfect. The ball soars. And he makes it look so easy” (The Daily News Online).
For Jim Taylor, golf is his life. The excitement and enthusiasm was apparent in his voice while talking to him over the phone about our project. He is eager to see our ideas and prototypes in person, so much so that Jim is planning on driving down from Washington to visit us in middle to late May. During his stay we will play a round of golf with Jim and have the opportunity to see how Jim uses his golf arms in person. In addition, Jim has expressed that he would like to share a few ideas with us regarding how he feels his golf prosthetics could be improved. We hope to learn a tremendous amount from Jim during his visit, and the feedback we receive will help us address many key issues with our ideas a help us make significant progress with our designs.
On April 3, 2011, two Kinesiology majors, Joe Ricci and Danielle Morrison, and our senior project team met with John Lawson. John Lawson is a bilateral arm amputee who lost his arms in an electrical accident. The doctors tried to save his right hand but ended up having to cut it off. His left amputation is about two to three inches below the elbow and his right amputation is about two to three inches above the wrist. He can create a fair amount of rotation with his right arm but none with his left. John lives in Ohio and comes to California often for acting jobs. He likes to come to San Luis Obispo for the Amp Surf organization. He seems very excited to give us insight on our designs.
He used to play golf with his brother and made a makeshift golf attachment. The golf attachment is very simple; every club has a pin glued on the shaft which then goes on to a block. The club can freely rotate 90 degrees around the pin. This design only allows movement in one degree of freedom. A sketch of his design is shown in Figure 8. John uses hooks on both of his prosthetic arms which are operated by shoulder movements. When John shrugs his shoulders he applies tension on the cable which is connected to a lever. The lever will open and close the hook. The hook is forced closed by many castration bands which give the hook a strong gripping force. John Lawson’s hooks have about 20 pounds gripping force which is much higher than the average hook. This is due to the increased number of castration bands applied to John’s hooks.
While removing his hooks, John first showed us how to remove the cable from the lever. Then he unscrews the hook. To put it back on, he places a washer on top of the threaded hole and then attempts to screw his hook back on. Each time he tried to screw it back on, the washer would fall on the ground. Ryan ended up helping him put it back on. This made us realize that it is unrealistic to make the amputees remove their hooks in the middle of a round of golf. It would take too long and it would require assistance.
John demonstrated to us that if he were to swing a golf club, the motion of the golf swing would inadvertently cause his left hook to open. John is not an avid golfer so it is unknown if that happens to all golfers who use cable assisted prosthetics. However, knowing this we are going to have to design a product that ensures that the golfer will not let go of the club accidentally during the golf swing. An interesting point to note is that John can easily detach the cable from the lever of his left prosthetic arm, which then permanently prevents his left hook from opening until the cable is reattached.
When asked if he would rather have a product that allows complete independent use or a product that looks like a natural golf swing, he said without hesitation that he would rather have a product that allows complete independence of use.
John said the hardest part of golf is teeing up the golf ball. He has to pick up both tee and ball at the same time and delicately place it in the ground. John said that the easiest part of golf is the short game and putting.
John is planning on coming back to California in May to help us further develop our prototypes.