Abstract
Patients with disorders such as Essential Tremors and Parkinson's Disease often lose their ability to write with a pen or pencil. This raises inconveniences in everyday living. A pen has been designed that enables many of these patients to sign their name, write etc. that works solely by mechanical principals, inertia of a spring suspended pen holder inside an outer case which resists movement when used by the patient holding the outer case. The pen can be carried in a large pocket, backpack, or briefcase. Prototypes of the pen have been made from easily available parts, such as PVC pipe, Al tubing, rubber bands, and lead fishing weights. Mass spring equations are presented to help model the optimum weight and rubber band tensions. This thesis builds on research by Dr. Kumagai of California State University Sacramento, a professor and graduate students Kosuke Naritomi, and Tyrone Tracy. They have designed and made a working model of the essential tremor pen and the model discussed here is an improvement in some aspects. The prototypes show that it is possible to design a pen that reduces the effect of tremors, using the proposed design, if the inertia in the pen body is optimised for the particular patiant, at least when the persons tremor is mild.