Search or add a thesis

Advanced Search (Beta)
Home > Stabilization of Perturbed Nonholonomic Systems in Chained Foam

Stabilization of Perturbed Nonholonomic Systems in Chained Foam

Thesis Info

Access Option

External Link

Author

Sarfraz, Muhammad

Program

PhD

Institute

Capital University of Science & Technology

City

Islamabad

Province

Islamabad.

Country

Pakistan

Thesis Completing Year

2018

Thesis Completion Status

Completed

Subject

Control Systems

Language

English

Link

http://prr.hec.gov.pk/jspui/bitstream/123456789/10461/1/Muhammad%20Sarfraz_Control%20Sys_2018_CUST_PRR.pdf

Added

2021-02-17 19:49:13

Modified

2024-03-24 20:25:49

ARI ID

1676727231682

Similar


Many real-world systems exhibit velocity-dependent and/or acceleration-dependent constraints in their mathematical models. If these constraints are non-integrable then these systems are known as nonholonomic systems. Examples of such nonholonomic systems include hopping robots, unmanned aerial vehicles (UAVs), car-like robots, autonomous underwater vehicles (AUVs), surface vessels, vertical take-oand landing systems and many more. These systems are special as, in general, the stabilization problem of these systems cannot be solved by smooth (or continuous) static state-feedback and, thus, requires time-varying or discontinuous state-feedback control. In this research, we are consideringrst-, secondand higher-order nonholonomic systems that can be transformed into chained or power form which are canonical representations of these mechanical systems. The importance of stabilization problem of perturbed nonholonomic systems is further magni ed by the variety of real-world day-to-day applications. This research presents the solution to the stabilization problems for a selected class of perturbedrst-, second- and higher-order nonholonomic mechanical systems. The methodologies are based on adaptive integral sliding mode control (AISMC). For the perturbed nonholonomic system, the original system is transformed into perturbed chained form. Then this perturbed chained form system is further transformed into a special structure containing nominal part and some unknown terms through input transformation. The unknown terms are computed adaptively. Later the transformed system is stabilized using integral sliding mode control (ISMC). The stabilizing controller for the transformed system is constructed which consists of the nominal control plus some compensator control. The compensator controller and the adaptive laws are derived in such a way that derivative of a Lyapunov function becomes strictly negative. A similar approach is applied to the third-order nonholonomic system with a jerk constraint. The validity of the proposed controllers is ascertained by simulating the perturbedrst-, secondand higher-order nonholonomic systems in MATLAB / SIMULINK. The proposed control algorithms globally steer the whole system to the origin.
Loading...
Loading...

Similar Books

Loading...

Similar Chapters

Loading...

Similar News

Loading...

Similar Articles

Loading...

Similar Article Headings

Loading...

102. At-Takathur/Striving for more

102. At-Takathur/Striving for more

I/We begin by the Blessed Name of Allah

The Immensely Merciful to all, The Infinitely Compassionate to everyone.

102:01
a. O The People!
b. Striving for more worldly riches distracts you from the Remembrance of Allah,

102:02
a. till you visit/reach the graves.

102:03
a. By no means!
b. You will soon get to know the consequences of your priorities in worldly life.

102:04
a. Once again, by no means!
b. You will soon get to know the consequences of your priorities in worldly life.

102:05
a. By no means!
b. You would not have been distracted from the reality of the Hereafter if you knew with certainty that you would be held accountable for the worldly life, you would not have preoccupied yourselves with it.

102:06
a. That you would definitely end up experiencing the Blazing Fire,

102:07
a. and again, if you knew that you would definitely end up seeing it with the very eye of certainty.

102:08
a. Then, at that Time, you will certainly be questioned about the bliss you enjoyed in the worldly life.

امثال القرآن کی ضرورت واہمیت

The Qur’an is the most-read book in the world. Revealed by Allah Almighty to Prophet Muhammad, and revered by Muslims as being Allah’s Final Scripture and Testament, its words have been lovingly recited, memorized and implemented by Muslims of every nationality ever since. The Quran is also the only holy book that can be memorized in its entirety by people of all ages and intellectual abilities – including non-Arabic speakers – which Muslims consider to be one of its miracles. The Holy Quran is the source guide; the purpose of Similitude in Qur’an is to get a lesson. In each instance there is knowledge to mankind, it possesses a particular utility. Allah ta’aala has invited to all mankind to consider the Quran, as in the Holy Quran” Do they not then think deeply in the Qur'an, or are their hearts locked up (from understanding it)?”. This article explains deeply about the Importance of Similitude of Qur’an.

Taxonomic Diversity and Phytosociological Dynamics of the Flora of Shishi Koh Valley, Chitral, Pakistan

The current research work was carried out during 2014-16 to study the taxonomic diversity and phytosociological dynamics of the flora of Shishi Koh Valley, Chitral, Pakistan. Gymnosperms were represented by two families Ephedraceae and Pinaceae. The dominant family was Pinaceae comprised of three (3) genera and four (4) species. In Angiosperms, Monocots were represented by five (5) families, seventeen (17) genera and twenty (20) species. Family Poaceae was found to be the dominant monocot family contributing thirteen (13) genera and sixteen (16) species. Dicots were represented by one hundred and thirty five (135) species belonging to ninety seven (97) genera of thirty eight (38) families. In dicots family Papilionaceae was found the dominant family represented by 12 genera and 22 species. Plant communities were studied in the Shishi Koh Valley, Chitral, Pakistan along an elevation gradient between 1831-2723m. Out of the total plants collected 13 (8%) were trees, 11 (7%) were shrubs and one hundred and thirty six (85%) were herbs. Five plant communities were established. Diagnostic, constant and dominant species were assigned based on fidelity threshold (40%), frequency threshold (25%) and cover threshold (35%) respectively. The communities were grouped into two main clusters on the basis of altitudinal variations. Cotoneaster-Rosa-Aristida and Pistacia-Quercus-Cannabis communities formed part of the first cluster. In the second cluster three communities were present in such a manner that Cedrus-Elaeagnus-Salix community formed part of the second cluster directly while the other two communities Cedrus-Ailanthus-Salix community and Abies-Cedrus-Pinus community were present as sub-groups of the second cluster. DCA1 axis had more contribution in overall variation of communities'' diversity in the research area. Biological spectrum of the vegetation in the research area revealed that dominant life from class was Therophyte (35.43%). Among the other life form classes Hemicryptophyte were 20.47%, Nanophanerophyte 14.96%, Geophyte 13.39%, v Megaphanerophyte (11.02%), Chamaephyte 3.94%) and Mesophanerophyte were 0.79%. The dominant leaf size class was Nanophyll (41.73%). Representation of the other classes was Mesophyll 25.98%, Microphyll 20.47%, Leptophyll 9.45% and Macrophyll 2.36%. In regard to leaf persistence, 87.40% plants were deciduous and 12.60% plants were evergreen. Simple leaves were present in 71.65% plants, compound in 22.05% while incised leaves were present in 6.30% plants. Spiny nature was shown by 9.45% plants while 90.55% plants were non-spiny. In relation to water present in the habitat wise 74.02% plants were in xeric, 23.62% in mesic while 2.36% plants inhabited moist and aquatic habitats. In response to light 94.49% plants were heliophytes while 5.51% were sciophytes. Analysis of minerals showed that soil samples collected from all the five communities in the research area have low concentrations of Cu, Fe and Zn as compared to Mn. While Ca and Mg were present in considerable amount in all the soil samples analyzed. Organic matter ranged from 0.3 to 2.77%. Organic matter was present in the highest range in the Abies-Cedrus-Pinus community. Analysis of soil samples obtained from the research area showed that most of the soils are very nutrient poor and less fertile as most of the area is arid therefore mostly supporting xeric annual plants. Although in all communities sand particles was much higher however soils were comparatively fine textured in Pistacia-Quercus-Cannabis community as compared to all others. The current study pointed out that the research area has great taxonomic diversity but plant communities are under the threats of overgrazing and medicinal plants collection. Similarly plant communities are mostly being exploited for fuel and furniture woods resulting in flood hazards each year. Another factor is overgrazing, mostly due to the herds of local gujjars and nomadic visitors in the start and middle of the valley. The herbaceous flora is under serious threat of extinction due to these devastating factors. Control measures must be taken to avoid further damages. Some rehabilitation programs may also be started to recover damage to the forests in the research area.