1.  Field of the Invention
This application describes embodiments of apparatuses, methods, and systems for the abrasion of skin in preparation for application of an electrode for detection of cardiac and other low level electrical signals generated within the human body, allowing for improved short term and long-term adhesion and improved conductance through skin, resulting in better signal quality of recorded data. 
2.  Description of the Related Art
Skin contact electrodes are used extensively for detecting and transforming potentials generated within the body into electrical signals which may be monitored for a variety of functions, such as the preparation of electrocardiograms and electroencephalograms.  Many disposable electrode assemblies and similar devices utilize an electrode together with an adhesive for holding the electrode in position on the skin.  For the best electrical contact with mammalian skin, it is desirable to remove hair and a portion of the epidermis, as well as surface oils.  Typically, the process involves removal of hair by shaving or other depilatory method.  Next, the skin is abraded for the removal of the dry layers of stratum corneum, followed by cleaning and defatting of the skin using an alcohol wipe.  The skin abrasion process exposes more conductive layers of skin to improve electric connection, promoting better transmission of a cleaner signal. 
As mentioned previously, electrodes may contain an adhesive to keep the electrode in contact with the skin.  The outer layers of the stratum corneum are typically the driest and nearest to being sloughed off by the body.  Removing these cells prior to electrode placement allows the adhesive to come into newer, more anchored layers of the skin, promoting longer adhesion performance.  With sensing applications that require longer-term wear periods, sufficient removal of skin takes on greater importance.  The development of a long-term recording ECG patch has further created a need for a tool that is effective in thoroughly removing the stratum corneum layers, to allow for patch adhesion for periods up to and beyond 14 days. 
As critical as the skin abrasion process is for good signal conduction and long term adhesion, it is a process that is often incomplete in practice.  This is largely due to the limitations of existing abrasion tools in combination with the limited time and attention typically given to the abrasion process.  Certain abrasion tools, resembling woven polymer sponges, have a coarse texture.  Though the sensation of abrasion is heightened for the patient, the contours of the tool's surface are more conducive to creating scratches in the skin than evenly removing the outer stratum corneum layer.  Other products, such as pumice-impregnated alcohol wipes, do an adequate job of abrading the skin without causing unwanted injury to the skin, however significant pressure and attention is required for an effective outcome.  In combining the skin abrasion and cleaning step into a single tool, these instruments are easily confused for alcohol wipes intended for just cleaning, and the pressure required for abrasion is not achieved. 
Because of the limitations of existing skin abrasion tools, there is need for a simple, one-piece, disposable and low-cost tool that can effectively abrade the skin while being easy to manipulate and that minimizes the amount of attention that must be given to this part of the prep process.