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Archive:Data acquisition system

2007-09-07T12:22:00Z

89.138.164.58: /* External Links */

{{clarify|December 2006}}

A '''data acquisition system''' is a device designed to measure and log some parameters. The purpose of the data acquisition system is generally the analysis of the logged data and the improvement of the object of measurements. The data acquisition system is normally electronics based, and it is made of hardware and software.
The hardware part is made of sensors, cables and electronics components (among which memory is where imformation are stored). The software part is made of the data acquisition logic and the analysis software (and some other utilities that can be used to configure the logic or to move data from data acquisition memory to a laptop or to a mainframe computer).
An example: [[Data logging]], carried out by a '''data acquisition system''' (DAS), can be used to measure parameters such as [[temperature]] and [[humidity]] in storage facilities with perishable products; the measurement data is then stored for analysis to improve quality assurance.
Another example: a '''data acquisition system''' can be placed on a race car to measure RPM and vehicle speed to analyze car's behaviour once it's back to pits and improve the car setup.

==Data logging systems==
Data logging systems consist of four elements:

#Measuring output ([[sensor]]s around the vehicle)
#Recording output signals (logger unit)
#Uploading/accessing recorded data ([[telemetry]])
#Analysis of recorded data. (DAS [[software]])

The 4 elements above have specific requirements which need to physically present and included in the design process. Sensors to measure selected parameters must meet certain specifications, and the routing of the sensor [[cable]]s ensures they will not suffer from [[electromagnetic]] interference from other electronic systems. The DAS unit (including [[memory]]) and the link from the DAS unit to the operating platform to upload the acquired data via a [[hardwire]] cable or telemetry also must conform to requirements.

Most [[race car]]s use two types of telemetry. The first is sent to the [[engineer]]s in the pits every time the vehicle acquires more than 50[[megabyte|Mb]] of data, containing an insight into the state of the vehicle. The second is transferred each time the vehicle is in the [[pit lane]], providing information on every part of the vehicle. With the most advanced telemetry, the data is sent constantly for analysis through a [[transmitter]] as long as a good connection is present (not always possible in parts of certain [[raceways]] due to obstruction).

The [[operating platform]] is required to include specialist analysis software to view the data, usually in the form of various [[graph]]s to improve and develop the performance of the key areas and operation parameters of the vehicles running conditions. The most advanced software in [[Formula 1]] has been developed by McLaren Electronics known as Advanced Telemetry Linked Acquisition System, which displays graphs of each of the vehicle's systems on the exact section of track, in a [[real time]] format. The benefits of using such a system include the fact that the parameters which can be recorded for analysis cover the whole set-up of the race vehicle (up to 127 [[channel]]s).

The parameters which are measured and recorded by a data acquisition system are broken into three generic categories, which are also interlinked due to system requirements and the complexity of major components (for example, a wheel [[speed]] sensor not only monitors the wheel speed but also the speed of the vehicle, location on the track and an input to [[traction]] and [[launch control (automotive)|launch control]] systems):

#'''[[Engine]]:''' [[Rev]]s per minute, fuel and [[oil]] pressure, water and oil temperature, [[turbo charger]] boost pressure, [[exhaust]] gas temperature, [[battery (electricity)|battery]] voltage, inlet air temperature and [[throttle]] position sensor.
#'''[[Chassis]]:''' Wheel speed, steering angle, [[lateral]] and [[longitudinal]] [[G-force]] (applied from braking and cornering), Brake line pressure, damper movement and gear position.
#*'''Advanced Chassis DAS''': Ride height, [[drive shaft]] or [[prop shaft]] [[torque]], [[Suspension (vehicle)|suspension]] loads, tyre pressure and compound temperature, and brake disk temperature. ''Optional'': [[aerodynamic]] parameters, including air speed and local air pressures.
#'''Driver:''' Both engine and chassis-related factors which are controlled by the driver, such as throttle position, gear position, steering angle and brake line pressure or directly controlled parameters such as engine revs per minute, speed and G-force.

The accurate information provided by telemetry sent by DAS in a practice run takes significant fine tuning, such as ensuring the correct [[gear ratio]]s are present according to track layout, or that the engine acceleration speed according to throttle position and sensitivity is set to the required conditions of a race. The engine control system will be programmed with suitable engine maps giving the driver more control of the throttle input. On a track with a large number of corners, the first part of pedal movement would be made very sensitive in order to effectively negotiate the course. On other courses, however, the vehicle might be required to come out of the [[chicanes]] and directly to peak power levels, thus less sensitivity required on the pedal.

The DAS during race time is monitored by engineers in the pit and [[garage]] area, who diagnose any faults which may occur. In this case, the DAS is used as an early warning system of potential mechanical failure, allowing the designers and material analysis team to easily distinguish the cause of the fault. This can result in a significant decrease of the danger to a driver.

A good example of this can be taken from the [[2003 British Grand Prix]], when engineers in the pits observed the loss of pressure from one of Coulthards tyres. The DAS allowed the team to recall him from his practice, resolving the fault before a dangerous situation occurred.

“Formula 1 telemetry is the technological lifeblood of the sport, helping the drivers and engineers to better understand how a car functions and how they can optimise its set-up.”{{Fact|date=February 2007}}
== External Links ==
**[http://www.remmon.com REMMON Remote Monitoring LTD]

Archive:Data acquisition system

2007-09-07T12:20:38Z

89.138.164.58:

Computer network

2006-12-23T21:09:57Z

89.138.43.201:

A '''computer network''' is a data communications system that interconnects computer systems at various different sites. Today we are going to learn about the pieces that make a network , some of which you are familar with:
*PC - Computer like the one your on now
*[[wikipedia:NIC|NIC]] - Network Interface card - This is both an electrical interface to the router/modem , and a logical board that communicates to the rest of the pc , usually registered jack forty five or registered jack eleven standard the cable to provide a carrier for the signals either shielded or unsheilded. When you connect to the Internet for example the nic should send out fast link pulses that try to establish the acceptable speed of connection between the computer and the modem/router on the global side. These pulses are of a fixed length - if one side can respond within x number of miliseconds it will communicate at y speed, assuming both sides are set to autonegociate. NIC has a Media access control or a Burned in address inside one of its microchips - this will NEVER change (though it can be falsified) unless you get a new nic.
*[[wikipedia:hub|hub]] - seldom used, this splits the connection betwen multiple PCs. It may regenerate the signal - or may just send it on
*switch - used to split multiple PCs into different groupings based on logical needs or security needs , within the same subnet or lan
*[[wikipedia:routes|router]] - used to send data between phyisical networks.
These are the basic parts of a network. These parts speak different languages called protocols, which are didived into routing and routed protocols. In the next lesson we will learn about different kinds of cabling and different languages such as RIP.

==[[wikipedia:OSI model|OSI Seven Layer Model]]==
*Layer 7, the '''Application layer''', privides service riderctly related to the applications. THose services vay on applications.
*Layer 6, the '''Presentation layer''', format the data to look like common for all applications
*Layer 5, the Session Layer, establishes a connection between two nodes. Deal with, whether the conneciton is [[wikipedia:Full duplex|full duplex]], [[wikipedia:Half Duplex|half duplex]] etc.
*Layer 4, '''Transport layer''', handles and delivers data, whenever it is conneciton-oriented or connecitonless. It includes some [[wikipedia:flow control|flow control]] issues.
*Layer 3, '''Network Layer''', establishes the connection between two nodes, suing the IP addressing.
*Layer 2, the '''Data Link Layer''', frames data and privodes low-level flow control
*layer 1, '''Physical layer''', transmits low bitstreats (data), deals with electrical singalling, [[wikipedia:Network cabling|cabling]] and hardware interface.

[[Category:Computer Science]]