ADVANCED FIBER INFORMATION SYSTEM

1. ADVANCED FIBER INFORMATION SYSTEM (AFIS)
Introduction:
 In textile industry raw material is the most dominant factor as it contributes 50-75% in total manufacturing cost.
 In quality conscious scenario, quality of raw material plays a vital role. But the quality of raw material is decided by
measuring its properties.
 Now measurement through conventional techniques is very laborious and time consuming.
 Hence the researchers focus their attention towards the inventions of such instrument, which gives accurate and
quick result and one of the wonderful development is AFIS - Advanced fibre information system.
BASICS PRINCIPLE:
The AFIS method is based on aeromechanical fibre processing, similar to opening and carding, followed by electro-
optical sensing and then by high speed microprocessor based computing and data reporting as shown in Figure.

3.  A fibre sample is introduced into the system and is processed through a fibre individualizer, which aero mechanically
separates the sample into three components consisting of cleaned fibre, micro dust, and trash.
 Each of these components is transported in a separate pneumatic path and may be analyzed electro-optically or by
other means.
 The data processing and reporting are handled by an industrialized PC.
AFIS provides basic single fibre information and is distinguished from earlier and existing methods by providing
distributions of the basic fibre properties. These distribution measurements provide more accurate, precise, and basic
information about fibre.

4. CONSTRUCTION AND OPERATION OF INSTRUMENT:
Fibre individualizer:
 The fibre individualizer (in Figure) uses unique cleaning and separating techniques to present the fibres
pneumatically to the electro-optical sensor.

5.  The fibres are opened and cleaned using specially designed, pinned and perforated cylinders, which are similar to
open end spinning beaters and stationary carding flats.
 Airflow into the perforations of the cylinder allows for thorough engagement and efficient dust and trash removal.
 A specimen of fibre is hand teased into a sliver-like strand and is inserted into the feed assembly.
 It passes between a spring-loaded feed roll/feed plate assembly and is engaged by the pinned and perforated
cylinder.
 The fibres are combed and carded; dust is released and removed through the perforations in the cylinder.
 Trash is released after the carding action by the "counter flow" separation slot.
 Heavy trash particles are separated from fibres and transported out of the system, whereas, the smaller dust and
fibres are returned to the cylinder aerodynamically by the air drawn into the slot, thus the term "counter flow slot".
A secondary stationary flat is used to further clean and comb the fibres. They are then directly transferred to a second
cylinder. A second "counter flow" slot removes additional trash. Its counter flow air is used to transport fibres out of the
system after a final combing from a third stationary carding flat. The separated components (cleaned fibre, micro dust
and trash) are transported along three different production paths.

6. Fibre individualizer motor/Motor controller:
 Versions 3 and 4 units have a separate drive motor for fibre individualizer.
 These brushless DC motors are noiseless in operation, allow for direct monitoring and control of the motor speed, and
are easier to service and replace.
 The brushless DC motor has its own motor controller board which monitors and controls and motor speed.
 The motor speed can be adjusted by a potentiometer located on the board.
Feed motor/Motor controller:
 Versions 3 and 4 units feed belts and feed rollers are driven via worm gear with a stepper motor.
 The motor speed is variable from 140 steps/sec to 1116 steps/sec.
 The feed motor controller is a motor driver that accepts pulses and direction information from the control board.
 The initial direction of the stepper is determined by the orientation of the motor's 7-pin plug on the controller.
 If the direction is "backward" after installation, reverse the plug.

7. Sliver detector:
 The sliver detector is located between the feed tray and feed plate.
 Its function is to signal the control system when sliver is being presented to the individualizer and when sliver is no
longer present.
 The sliver detector consists of an infrared LED source and detector.
 During operation, the sliver (fibre specimen) passes between the source and detector 'breaking" the beam which
signals the control board to slow the feed rate to the sampling speed.
 When the trailing end of the sliver passes through the source/detector the beam is "made" once again.
 A 15second delay is triggered to allow the remaining sliver to continue processing through the system before the
"end of sample" sequence is initiated by the control board.
Electro-optical sensors:
 The electro-optical (E-O) sensors consist of three basic elements tapered entrance and exit nozzles (on Version 4 lint
sensor, a single piece accelerating nozzle) beam forming and collection optics.
 The detection circuitry (in Figure).

9. Individualized fibres (and neps) are transported pneumatically from the fibre individualizer by an air stream. They enter
the E.O. sensor through an accelerating nozzle which straightens, separates, and aligns the fibres in proper orientation
to the source detector. The fibres penetrate a collimated beam of light and scatter and block that light in proportion to
their optical diameter and in direct relation to their time of flight through the sampling volume.
Generally, rectangular waveforms are produced by the light scattered by individual fibres. Nep signals are much greater
in magnitude and duration and generate a characteristic nep "spike". Trash particles produce smaller spiked waveforms,
which are distinguishable from neps in magnitude and duration.
From these waveforms, which are microseconds in duration, the pertinent data are acquired, analyzed and stored in the
host computer. Distributions based on size, length or diameter can be generated.

10. DATA ANALYSIS:
I) Lengths by number (n):
Fibre length by number is the length of the individual fibres. This method measures the length of each fibre and
places them into length categories.
These categories are added together to obtain the length measurement for short fibre and average or mean length.

11. Length by number measurements is pure measurements that are not influenced by the weight of the fibres. Typically
this means that the length by number results are always shorter than the same sample tested using the by weight
method. In textile processing, it is recommended that the length by number be used to determine machine and
equipment settings and also to determine fibre damage as represented by short fibre content. Instrument such as the
AFIS is capable of providing the length by number information.
II) AFIS Trash data Analysis:

12. The Advanced Fibre Information System (AFIS) was developed to measure traditional fibre neps (entanglements) often
times called mechanical neps.
A recent breakthrough development has furthered the technology for classifying neps into two categories fibre neps
and seed coat neps. AFIS nep classification is the newest addition to the modular AFIS system providing a more detailed
summary of nep type imperfections from ginned cotton through carded and combed sliver.
III) Seed coat nep detection method:
 The lint channel contains fibres, short fibres, mechanical neps and seed coats with fibres attached.
 The trash channel contains trash, dust, some fibre fragments and very large seed coats with little or no attached
fibre.
 The seed coats, which remain with the fibre during opening are termed seed coat neps by the AFIS.
 These are masses that are most likely to remain with the good fibre during the textile opening, cleaning, carding, and
combing processes.
 Large seed coats, termed seed coat fragments, are collected in the trash port of the AFIS and are more easily
removed from the fibre.

14.  As illustrated in Figure, the fibre individualizer separates the sample in to three main components: lint, trash, and
dust.
The AFIS nep classification module counts and sizes seed coat neps. The classification module is able to identify the
distinct electrical waveforms produced by fibres, fibre clumps, seed coat neps, etc. This improved nep module uses a
digital signal processor (DSP) to classify all incoming waveforms and to calculate nep size. Figure illustrates a typical nep
waveform and the values extracted by the standard nep module. Figure illustrates the same signal analyzed by the DSP
system. The DSP system is capable of recording and analyzing all information contained in the nep signal, therefore
providing better information about the sample characteristics. The classification software compares each sampled
waveform to a standard waveform to determine which classification it most resembles. These standard waveforms are
based on models of seed coat neps and mechanical neps travelling through the sensor and are verified on numerous
simulations using manually introduced fibre neps and seed coat neps.

15. AFIS APPLICATIONS:
(1) Card nep analysis:
 Neps are created by mechanical handling and cleaning of cotton fibres.
 Due to fibre individualizer provided inside the machine we can analyze neps hence we can check nep in carded or
combed sliver.
(2) Card wire maintenance analysis:
 We can judge the grinding frequency required for card wires by appropriate checking of sliver quality on AFIS instrument.
(3) Length applications
 This instrument will provide various fiber length data so that it will be helpful to control the imperfection in the final yarn.
(4) Length analysis of comber and D/F:
 This instrument provides the data on histogram i.e. in form of fibre distribution so it will give accurate idea about length.
(5) Trash application:
 By using this instrument we come to know the exact amount of trash present in material so that we can decide the
material is suitable for processing or not.
ADVANTAGES:
 High degree of accuracy, which gives precise results.
 Testing speed is high.
 It avoids laborious time work needed for measurement of nep count.
 The results are free from human and machine error.
 It can analyze process performance.