Nowadays technological systems are designed to meet the growing demands for safety and performance. This is emphasized especially for safety-critical applications such as aviation, aerospace or nuclear systems. Even small unnoticed and seemingly insignificant error or incorrect reaction to the error ca lead to catastrophic failure of the entire system. New control techniques and design approaches are developed to avoid fatal failures. These novel techniques and approaches are also able to adjust the required levels of performance including stability of the overall system in addition to ability to handle faults of the system. Such control systems are called fault tolerant control systems. Ability to achieving a certain level of system performance during occurence of fault in system components is sign of a degree of redundancy in the system. However reaching the level of performance may be limited by physical or economical means. Effective solution to this situation is to reduce the performance demands on system. Sometimes requirements have to be reduced to the stabilization only of the most important parts of the system. During occurence of the fault of one actuator the entire system and its performance depends on rest of actuators and their performance li, etc. and its performance depends on component limits. Therefore it is important to avoid excessive load of actuators and thus the risk of failure of the system. Often the remaining actuators are used to achieve state of the system that is considered to by safe instead to continue the task. The paper presents three different methods for control reconfiguration using virtual actuators that stabilize the system with the faulty actuator. Control algorithms as well as the conditi... ... middle of paper ... ...ther actuator is added in following simulations to replace actuator during failure so number of outputs of the system is equal to number of inputs. Extended nominal system and extended system with fault is used similarly as in previous part. In case of failure of the first actuator all state space variables are stabilized at desired values without permanent control deviation after start of the virtual actuator in time 70 seconds. Respons of the system can be seen on the following figure. Further simulations of virtual actuator with integral part are performed with extended system during failure of the third and fourth actuator. Goal of weak reconfiguration is accomplished simillarly as in previous part. Controlled variables achieve desired values hovever uncotrolled variables stabilize at non-zero values. Simulation results are summarized in following table.
Disaster recovery is a useful feature of virtualization. Snapshots of your server can be taken regularly and as often as you prefer. Then, you can use any one of those snapshots to return your server to a particular configuration from a particular point in time. For example, before your network was infected by a virus.
...ial approaches which are Normal Accident and HROs, although it seems certain that both of them tends to limit the progression that can contribute toward achieving to highly protective systems. This is because the scope of the problems is too narrow and the potential of the solutions is too limited as well. Hence, Laporte and Consolini et.al., (1991) as cited in Marais, et.al., (2004) conclude that the most interesting feature of the high reliability organization is to prioritize both performance and security by the managerial oversight. In addition, the goal agreement must be an official announcement. In essence, it is recommended that there is a continuing need in the high risk organizations for more awareness of developing security system and high reliability environment in order to gain highly successful method to lower risk in an advance technology system.
A single point of failure refers to the failure of a component that can terminate
Virginia Polytechnic Institute and State University will evaluate operational and technical risk areas. They will conduct UAV’s failure mode.
This is where means of a robotic device perform surgery– controlled by a human surgeon, which time and risk of complications are reduced. Virtual reality has been also being used for training purposes and, in the field of remote tele surgery in which the surgeon perform a surgery at a separate location to the patient. The main feature of this system is force feedback as the surgeon needs to be able to measure the amount of pressure to use when a delicate procedure is performed. However, there is an issue of time delay or latency which is a serious concern as any delay – can feel abnormal to the surgeon and interrupt the procedure. So there needs to be precise force feedback to prevent
Gaining a better understanding of when electronics are about to fail can help engineers and companies be more effective in providing reliable electronics; this will also lead to a greater return on investments for businesses (Seggie, Cavusgil, & Phelan, 2007). Prior attempts of implementing algorithms have all failed due to the large bandwidth required to process the data in real time. The algorithms in this study will not require many resources and will use simple gate-logic and statistical data to alert an end-user of a potential failure. Scores, which are based on inputs from the end-user, for each of the four factors, will serve as the four independent variables for this study: (a) cost, (b) reliability, (c) component replacement, and (d) total system replacement.
Another example of a suspension system is called the double wishbone suspension, or the A-arm system. This system is said to be the most ideal suspension to many suspension designers. It can be used both in the front and in the rear of the car, is an independent suspension, and is most desirable because of its n...
...mpany up and running through any kind of interruptions such as power failures, IT system crashes, natural or man-made disasters, supply chain/vendor problems and more.
4. When the brake assist operates, if the driving force deliberately releases the lever, the
The primary cause is of airplane accidents does at some stage contain an element of a person being unable to discharge his duties correctly and in an accurate manner. More than 53% accidents are the result of ignorance or faults by the pilot during flight. Other staff is responsible for about 8% accidents. The most obvious errors by pilot are made during the take off or landing on the runway. Additionally errors can occur during the maintenance of the airplane outside the plane, whereby a lack of thorough inspection and oversight can lead to complication during mid-flight. Fueling and loading of the plane also sometimes create problems (Shapiro, 2001).
Preventive maintenance can be defined as an activity performed on a certain schedule which is intended to prevent breakdowns or deterioration. These activities can include regular inspection along with solving any discovered problems or situations and regularly scheduled parts changes. Preventive maintenance involves the scheduled adjustment, inspection, replacement of wearable parts, calibrations, basic cleaning and lubrication of equipment or other recommendation made by the equipment manufacturer. These activities can help increase the equipment functional life and help decrease facilities deterioration. No equipment should, No equipment should reach the breaking point [1].
Virtual Reality also lends a hand to patients in order to recover from injuries such as a stroke. Doctors are utilising Virtual Reality to assists muscle movement to get back to normality, for instance, “walking and grabbing as well as smaller physical movements such as pointing”. The doctors use the malleable automated situation to enhance or reduce the movement which is required to hold or shift an item. This also assists in recording accurately, the speed of how fast a patient is learning and getting better.
The term of virtual reality was found by Jaron Lanier a founder of VPL researcher at 1989.He is also known as an American writer, computer scientist and composer of classical music. Virtual reality is computer generated 3D environments which user can enter and interact with virtual environment by using of electronic devices such as keyboard, mouse, wired glasses, shutter glasses its involves real time simulation. “The user able to “immerse” themselves to varying degrees in the computer s artificial world which may either be a simulation reality” ( (Pont, 1995) .Virtual reality is for human to visualize with auditory and touch sensation. There are few types in virtual reality which are immersive virtual reality, argument virtual reality, desktop virtual reality and video mapping reality. Immersive virtual reality system make user feeling involvement in the virtual world and equipped with Head Mounted Display known as HMD. Another type is argument virtual reality .Argument virtual reality is integrate computer generated virtual objects into physical world. Furthermore, desktop virtual reality involves three dimensional (3D) on regular desktop without any tracking equipment like playing games. Lastly, video mapping virtual reality allows user interact with body like jumping, hand move with the virtual world. The often hardware are use in virtual reality which are Head Mounted Displays, glove, stereoscopic displays will make user feel of in virtual world when they use these hardware’s although they in real world. Technological development in virtual reality 3D help many area like education, medical, surgery, manufacture, military, architecture, entertainment, prototype and so on. It...
Virtual reality is a new exploration in science and technology using advanced and complex mechanics. Virtual reality allows for users to go far beyond simply looking at a computer screen. Instead, the user puts on a special suit or gloves equipped with fiber-optic sensors. These fiber-optic sensors are able to interpret body positions. The user also wears special goggles that have video screens and audio attachments. This equipment allows for the user's complete immersion into a 3-D, computer generated, model of reality (Carr 37). The use of a two-way data transfer is what enables this interaction with an alternate reality to occur. Fiber-optic and electronic cables are attached to the virtual reality equipment in order to record the user's movements (Newquist 93). These cables then send this information, called motion data, to workstations which modifies the graphics in the model. The new information is then sent back to the users headset, displaying a graphic and audio world that is time with his or her movements. It is because of this cabling process that the action/reaction information is continually updated (93).
systems are able to run for the most part by themselves. For this paper, I will be discussing