Cable Stripper
PURPOSE OF THE RESEARCH \r The purpose of this project is to provide a cost-effective and efficient way of \r stripping electrical conductors, with thicknesses of 16mm up to 70mm in diameter, \r of their isolation. The current methods that are available are unsafe and unpractical. \r Therefore this project determines a safe way of stripping cables and also provides a \r new product to improve the worker’s safety during the process of stripping cables. \r PROCEDURES \r The solution can be found by doing research on the types of cable isolations \r currently on the market. By talking to the workers who use these types of tools, and \r strip these types of cables on a daily basis, I can comprehend the problems posed by \r the present methods and provide a solution. \r DATA \r An electrical cable is commonly a conductive wire surrounded by a nonconductive, \r insulation sleeve. In order to splice two cables together or connect the \r cable to an electrical device, the conductive wire inside the sleeve needs to be \r exposed. \r Numerous tools have been developed for slitting and stripping the electrical \r cable in order to expose the said conductive wire. The simplest tool is a knife with \r which the user makes an annular cut in the sheathing. The end portion of the \r sheathing then is pulled away exposing the individually insulated wires and the bare \r ground wire. The knife may also be used to cut away a short portion of the \r insulation at the ends of the wires. During both operations the user has to be \r extremely careful, or else the knife blade may damage the insulation around the \r internal wires and even nick the conductor or he may injure himself. To do so the \r user must first cut away several inches of the plastic sheathing at the end of the \r cable. A short length of the insulation then is removed from around each end of the \r conductors. \r As an alternative to using a knife, various scissors-like wire strippers have been \r developed. Although such scissors-like wire strippers are effective for removing the \r insulation from individual wires within an electrical cable, they are not efficient for \r removing the sheathing from the end of the cable in order to expose the individually \r insulated wires. \r A disadvantage of using a conventional knife and with using the known wire \r stripper is that a cable having a relatively thick insulation sleeve is difficult to strip \r and thus prepare for connections, since conventional wire stripping tools and other \r conventional devices, such as knives or tools with enclosed blades are inefficient for \r stripping thicker cable jackets. \r A further disadvantage of the known wire strippers is that, its basic \r characteristic dictates that the degree of friction between the tool and the wire after \r the insulation has been ringed will be high. This occasions no particular difficulty \r when only a short length of insulation is to be removed from the end of the wire. \r However, when yards and yards of insulation are to be stripped, as may be the case \r when reel ends are to be prepared for scrapping, the conventional wire stripper \r generates so much friction that it cannot be efficiently utilised. \r CONCLUSION \r The developed product enables workers to effectively strip electrical \r conductors without any impeding danger to themselves or the risk of damaging said \r cable. It is cost-effective and saves a lot of time. After several tests of the product no \r problems have been encountered up to this point.
The Actuator
The purpose of the Actuator is to create a practical device that passively exercises\r the lower legs to help prevent blood clots, Deep Vein Thrombosis (DVT), in\r wheelchair-bound individuals of any age. The secondary purpose of the device is to\r improve range of motion of the lower legs and speed the recovery of their leg action. It is hoped that this invention will help to prevent DVT, and allow some people to even use their legs again, through passive or active muscular motion. The invention was produced using a number of prototypes and design sketches. Although the current model is quite functional, as it keeps the users legs in motion, it is still in the prototypic design stage.\r The Actuator is a simple to use, easy to retrofit device. It is also portable and will be\r able to attach onto the front of any wheelchair. It harnesses the motion of the wheelchair to drive the users legs in a circular motion.\r The invention was tested in a closed and controlled environment: the duration of the\r Actuator’s use was constant, a doctor was present to take blood pressure and heart rate, and the rotation speed of the user’s legs was controlled by keeping the wheelchair speed constant. The data was collected by monitoring heart rate and skin surface temperature of healthy individuals, and blood pressure and heart rate of a wheelchair bound individual.\r As seen with both experiments (wheelchair bound, and healthy individuals) heart rate\r increased. In addition, the wheelchair bound individual’s heart rate also noticeably\r increased, with an evident increase in blood pressure as well. However, skin surface\r temperature is sensitive to surroundings and often provides little indication of deep vein blood flow, thus the skin surface temperature measurements were too inaccurate for any conclusions to be formulated.\r The inventor’s grandmother had developed DVT’s in 2005, and passed away because of them. Had she been given an Actuator it may have prevented such a tragedy. Her death was the driving force behind the project’s development. Over the time period that this project has been in process, the true potential of this invention has been realized.\r I truly believe that it will revolutionize the way that we treat people in wheelchairs, and the way people in wheelchairs can treat themselves.
Up the Creek
After an annual swimming rally in the Nahoon river, concerns were raised after several swimmers fell ill, complaining of possible symptoms of mild E.coli infection. Research was hence conducted to determine the following: \r \r \r The Nahoon River is safe for recreational activity in terms of faecal-coliforms and E.coli \r \r \r Whether the amount of rainfall affects these levels. \r \r \r If faecal pollution is present, to determine the possible point sources of the pollution \r \r \r To devise a method that needs no assistance from a laboratory, and could be done in a home environment at low cost. \r \r \r \r Procedures \r Colilert-18, (the reagent) contains nutrients which react to faecal-coliforms and E.coli in the sample. It causes samples to change colour when contamination is present. A dilution method (used by the Kowie Catchment Campaign) was used to test the severity of the contamination. The dilution levels were as follows: 1, 1/10, 1/100 and 1/1000. A control test was also performed. One Colilert capsule was divided among the five samples, which were incubated in a household stove at 37ºC for 18 hours. A sample was collected every four days and after heavy rainfall. \r The results were rated on a severity scale of 0-4, where a two was considered unsafe for recreational activity. If the undiluted sample remained clear, it was ra ted 0, if all the samples changed colour, it was rated as a four. The same rating system was used when fluorescing samples to test for E.coli. The daily rainfall level was compared to the levels of faecal-coliforms and E.coli. \r Conclusion \r As it has high levels of faecal coliforms and E.coli, the Nahoon River is not safe for recreational activity on a daily basis. \r Heavy rainfall causes the levels of E.coli and faecal coliforms to rise. \r The major source of the contamination is a stream entering the river from a newly developed settlement, and not a leaking sewer. \r This experiment has developed cost-effective home environment testing method which could be used in researching other rivers, marine environments, recreational waters and even drinking water by community researc