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1
Vaughan, Joshua Eric. "Dynamics and control of mobile cranes." Diss., Atlanta, Ga. : Georgia Institute of Technology, 2008. http://hdl.handle.net/1853/24736.
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Thesis (Ph.D.)--Mechanical Engineering, Georgia Institute of Technology, 2009.Committee Chair: William Singhose; Committee Member: John-Paul Clarke; Committee Member: Kok-Meng Lee; Committee Member: Patricio Vela; Committee Member: Rhett Mayor.
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Sorensen, Khalid Lief. "A Combined Feedback and Command Shaping Controller for Improving Positioning and Reducing Cable Sway in Cranes." Thesis, Georgia Institute of Technology, 2005. http://hdl.handle.net/1853/6853.
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Bridge and gantry cranes are crucially important elements in the industrial complex; they are used in many areas such as shipping, building construction, steel mills, and nuclear facilities, just to name a few.
These types of systems tend to be highly flexible in nature, generally responding to commanded motion with oscillations of the payload and hook. The response of these systems to external disturbances, such as wind, is also oscillatory in nature. Often, the oscillations of the hook and payload have undesirable consequences. For instance, precise manipulation of payloads is difficult when cable sway is present. Oscillation of the hook can also present a safety hazard. For these reasons, the ability to successfully negate these detrimental dynamics can result in improved positioning, quicker settling time, and improved safety.
This thesis addresses the dynamic properties of bridge and gantry cranes in an effort to develop a control scheme that enables strides to be made in these areas of positioning, efficiency, and safety.
The fundamental advancement arising from this thesis is the development of a control scheme that enables precise positioning of the payload while motion and disturbance-induced oscillations are eliminated. A command generation technique uniquely suited for reducing oscillation in low-frequency flexible systems is examined and utilized in the control. The control scheme is implemented on a 10-ton bridge crane for validation purposes.
3
Rauch, Andreas. "Stability analysis of mobile boom cranes." Thesis, Atlanta, Ga. : Georgia Institute of Technology, 2008. http://hdl.handle.net/1853/26535.
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Thesis (M. S.)--Mechanical Engineering, Georgia Institute of Technology, 2009.Committee Chair: William Singhose; Committee Member: Nader Sadegh; Committee Member: Wayne J. Book. Part of the SMARTech Electronic Thesis and Dissertation Collection.
4
Peng, Chen Chih. "Interfaces and control systems for intuitive crane control." Thesis, Atlanta, Ga. : Georgia Institute of Technology, 2009. http://hdl.handle.net/1853/31782.
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Thesis (M. S.)--Mechanical Engineering, Georgia Institute of Technology, 2010.Committee Chair: Singhose, William; Committee Member: Sadegh, Nader; Committee Member: Ueda, Jun. Part of the SMARTech Electronic Thesis and Dissertation Collection.
5
張大任 and Tai-yam Cheung. "Evolutionary design of fuzzy-logic controllers for overhead cranes." Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 2001. http://hub.hku.hk/bib/B31243010.
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Cheung, Tai-yam. "Evolutionary design of fuzzy-logic controllers for overhead cranes /." Hong Kong : University of Hong Kong, 2001. http://sunzi.lib.hku.hk/hkuto/record.jsp?B23636543.
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Manning, Raymond Charles. "Improving the control of two-mode flexible systems with input shaping." Thesis, Atlanta, Ga. : Georgia Institute of Technology, 2008. http://hdl.handle.net/1853/22566.
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Ramesh, Periyakulam S. "Experimental design and results of 2D dynamic damping of payload motion for cranes." Thesis, This resource online, 1994. http://scholar.lib.vt.edu/theses/available/etd-07102009-040346/.
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Chui, Yun Chuen. "Coordinated scheduling with two automatic stacking cranes in a container block /." View abstract or full-text, 2009. http://library.ust.hk/cgi/db/thesis.pl?IELM%202009%20CHUI.
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Shang, Jin. "Solution techniques for a crane sequencing problem." Morgantown, W. Va. : [West Virginia University Libraries], 2006. https://eidr.wvu.edu/etd/documentdata.eTD?documentid=4539.
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Thesis (Ph. D.)--West Virginia University, 2006.Title from document title page. Document formatted into pages; contains viii, 99 p. : ill. (some col.). Includes abstract. Includes bibliographical references (p. 93-99).
11
Ak, Aykagan. "Berth and quay crane scheduling problems, models and solution methods /." Diss., Atlanta, Ga. : Georgia Institute of Technology, 2008. http://hdl.handle.net/1853/26652.
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Thesis (Ph.D)--Industrial and Systems Engineering, Georgia Institute of Technology, 2009.Committee Chair: Erera, Alan L.; Committee Member: Ergun, Ozlem; Committee Member: Savelsbergh, Martin; Committee Member: Tetali, Prasad; Committee Member: White III, Chelsea C.. Part of the SMARTech Electronic Thesis and Dissertation Collection.
12
Ruddy, Thomas A. "Anti-sway control of a construction crane modeled as a two-dimensional pendulum." Thesis, This resource online, 1994. http://scholar.lib.vt.edu/theses/available/etd-12302008-063756/.
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Fujioka, Daichi. "Tip-over stability analysis for mobile boom cranes with single- and double-pendulum payloads." Thesis, Georgia Institute of Technology, 2010. http://hdl.handle.net/1853/37162.
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This thesis investigated a tip-over stability of mobile boom cranes with swinging payloads. Base and crane motion presents a tip-over problem. Attaching complex payloads further complicates the problem. They study began with a single-pendulum payload to analyze a tip-over stability characteristics under different conditions. A simple tip-over prediction model was developed with a goal of limiting a computational cost to a minimum. The stability was characterized by a tip-over stability margin method. The crane's tip-over stability was also represented by the maximum possible payload it can carry throughout the workspace. In a static stability analysis, mobile boom crane was assumed to be stationary, thus with no payload swing. The study provided basic understanding on the relationship between tip-over stability and boom configuration. In a pseudo-dynamic stability analysis, the method incorporated payload swing into the analysis by adding estimated maximum payload swing due to motions. To estimate the angles, differential equations of motions of payload swings were derived. The thesis extended the study to a double-pendulum payload. The maximum swing angles estimated in the single-pendulum case were directly applied to the double-pendulum case. To validate the analytical methods, a full dynamic multi-body simulation model of a mobile boom crane was developed. The predictions from the previous analysis were verified by the simulation results. The prediction model and the analytical methods in the thesis provide a significant tool for practical application of tip-over stability analysis on mobile boom cranes. The experimental results increase the confidence of the study's accuracy.
14
Danielson, Jon David. "Mobile boom cranes and advanced input shaping control." Thesis, Atlanta, Ga. : Georgia Institute of Technology, 2008. http://hdl.handle.net/1853/24651.
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Tsang, Wan-sze, and 曾韻詩. "Genetic algorithm for scheduling yard cranes in port container terminals." Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 2003. http://hub.hku.hk/bib/B29544609.
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Hernandez, Eileen Cynthia. "Dynamic characterization and analysis of aerial lifts." Thesis, Georgia Institute of Technology, 2012. http://hdl.handle.net/1853/45944.
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Aerial lifts are used to elevate people and material to high heights. There are many different types of aerial lifts which have vastly different dynamics characteristics. Thus, a new categorization for aerial lifts was created and organizes them by their kinematics. Many accidents occur while using aerial lifts. Hazards of aerial lifts and current solutions to those hazards were reviewed to understand the causes of the accidents. Some major accidents are due to the complex dynamics and flexibility of aerial lifts, such as oscillations and tip-overs. Oscillations of full-size aerial lifts were experimentally tested to determine frequencies in different configurations. Machine-motion induced oscillations of an articulating aerial lift were simulated and analyzed for both non-overcenter and overcenter configurations. Input shaping was used to achieve reduction in machine-motion induced oscillations. Tip-over stability margin was used to simulate and analyze the stability of both non-overcenter and overcenter configurations. The effect of increased platform mass on tip-over stability margin was also analyzed. The results in this thesis are a categorization of aerial lifts including their hazards and methods of reducing those hazards, an experimental verification of the dynamic response of full-size aerial lifts, a fully dynamic tip-over prediction model of double-boom articulating aerial lift by applying flexibility in the joints and realistic velocity profiles, and a detailed study of the dynamics of a double-boom articulating aerial lift.
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Maleki, Ehsan A. "Control of human-operated machinery with flexible dynamics." Diss., Georgia Institute of Technology, 2013. http://hdl.handle.net/1853/50305.
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Heavy-lifting machines such as cranes are widely used at ports, construction sites, and manufacturing plants in a variety of material-transporting applications. However, cranes possess inherent flexible dynamics that make fast and precise operation challenging. Most cranes are driven by human operators, which adds another element of complexity. The goal of this thesis is to develop controllers that allow human operators to easily and efficiently control machines with flexible dynamics. To improve the ease of human operation of these machines, various control structures are developed and their effectiveness in aiding the operator are evaluated. Cranes are commonly used to swing wrecking balls that demolish unwanted structures. To aid the operator in such tasks, swing-amplifying controllers are designed and their performance are evaluated through simulations and experiments with real operators. To make maneuvering of these machines in material-transporting operations easier, input-shaping control is used to reduce oscillation induced by operator commands. In the presence of external disturbances, input shaping is combined with a low-authority feedback controller to eliminate unwanted oscillations, while maintaining the human operator as the primary controller of the machine. The performance and robustness of the proposed controllers are thoroughly examined via numerical simulations and a series of experiments and operator studies on a small-scale mobile boom crane and a two-ton dual-hoist bridge crane.
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Maleki, Ehsan A. "Dynamics and control of a small-scale mobile boom crane." Thesis, Georgia Institute of Technology, 2010. http://hdl.handle.net/1853/37166.
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Boom cranes are one of the most dynamically complicated types of cranes because they possess rotational joints as opposed to the linear tracks of bridge and gantry cranes. In addition, if the boom crane is placed on a mobile base, additional complexity is added to the system. However, mobile boom cranes have huge potential benefits as they can be quickly transported from one location to another. Furthermore, if they utilize their mobile base during lifting operations, then they can have an extremely large workspace. All cranes share the same limiting weakness; the payload oscillates when the crane moves. A command-generation approach is taken to control the payload oscillation. Input shaping is one such command-generation technique that modifies the original reference command by convolving it with a series of impulses. The shaped command produced by the convolution can then move the crane without inducing payload oscillation. Input shaping can accommodate parameter uncertainties, nonlinearities, multiple modes of vibration, and has been shown to be compatible with human operators. This thesis focuses on three aspects of mobile boom cranes: 1) dynamic analysis, 2) input-shaping control, and 3) experimental testing. A majority of the thesis focuses on analyzing and describing the complicated dynamics of mobile boom cranes. Then, various input-shaping controllers are designed and tested, including two-mode shapers for double-pendulum dynamics. In order to experimentally verify the simulation results, a small-scale mobile boom crane has been constructed. The details of the mobile boom crane and its important features are presented and discussed. Details of the software used to control the crane are also presented. Then, several different experimental protocols are introduced and the results presented. In addition, a set of operator performance studies that analyze human operators maneuvering the mobile boom crane through an obstacle course is presented.
19
Huey, John. "Dynamics and vibration control of large area manipulators." Thesis, Georgia Institute of Technology, 2003. http://hdl.handle.net/1853/16469.
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Jacobs, Laura Diane. "Shake table experiments for the determination of the seismic response of jumbo container cranes." Diss., Georgia Institute of Technology, 2010. http://hdl.handle.net/1853/37200.
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Container cranes represent one of the most critical components of ports worldwide. Despite their importance to port operations, the seismic behavior of cranes has been largely ignored. Since the 1960s, industry experts have recommended allowing cranes to uplift, believing that it would limit the amount of seismic loading. However, modern cranes have become larger and more stable, and the industry experts are now questioning the seismic performance of modern jumbo cranes.
The main goal of this research was to experimentally investigate the seismic behavior of container cranes from the general elastic behavior through collapse, including non-linear behavior such as buckling and cross section yielding, utilizing the 6 degree-of-freedom shake tables at the University at Buffalo. The testing was divided into two phases. The first phase of testing was conducted on a 1/20th scale model. The second phase of testing was conducted on a 1/10th scale model, which was designed such that no inelastic action would develop prior to uplift (as is the common design practice). In support of the experiments, finite element models were created to determine what simplifications could be made to the structure to aid in testing. The data collected from the testing has been used to validate finite element models, to give a better understanding of the behavior of container cranes under seismic excitations, validate fragility models, and to develop recommendations and guidelines for the design and testing of container cranes.
21
Wen, Charlie Hsiao Kuang. "Heuristic approaches for crane scheduling in ship building." Master's thesis, Mississippi State : Mississippi State University, 2008. http://library.msstate.edu/etd/show.asp?etd=etd-07012008-141639.
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Wang, Lei. "Quay crane scheduling at container terminals : reducing the maximum tardiness of vessel departures /." View Abstract or Full-Text, 2003. http://library.ust.hk/cgi/db/thesis.pl?IEEM%202003%20WANGL.
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Thesis (M. Phil.)--Hong Kong University of Science and Technology, 2003.Includes bibliographical references (leaves 40-42). Also available in electronic version. Access restricted to campus users.
23
Kosbab, Benjamin David. "Seismic performance evaluation of port container cranes allowed to uplift." Diss., Georgia Institute of Technology, 2010. http://hdl.handle.net/1853/33921.
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The seismic behavior of port container cranes has been largely ignored-by owners, operators, engineers, and code officials alike. This is despite their importance to daily port operations, where historical evidence suggests that port operational downtime following a seismic event can have a crippling effect on the affected local, regional, and national economies. Because the replacement time in the event of crane collapse can be a year or more, crane collapse has the potential to be the "critical path" for post-disaster port recovery. Since the 1960's, crane designers allowed and encouraged an uplift response from container cranes, assuming that this uplift would provide a "safety valve" for seismic loading; i.e. the structural response at the onset of uplift was assumed to be the maximum structural response. However, cranes have grown much larger and more stable such that the port industry is now beginning to question the seismic performance of their modern jumbo container cranes.
This research takes a step back, and reconsiders the effect that uplift response has on the seismic demand of portal-frame structures such as container cranes. A theoretical estimation is derived which accounts for the uplift behavior, and finds that the "safety valve" design assumption can be unconservative. The resulting portal uplift theory is verified with complex finite element models and experimental shake-table testing of a scaled example container crane. Using the verified models, fragility curves and downtime estimates are developed which characterize the risk of crane damage and operational downtime for three representative container cranes subjected to a range of earthquakes. This research demonstrates that container cranes designed using previous and current standards can significantly contribute to port seismic vulnerability. Lastly, performance-based design recommendations are provided which encourage the comparison of demand and capacity in terms of the critical portal deformation, using the derived portal uplift theory to estimate seismic deformation demand.
24
Lawrence, Jason William. "Crane Oscillation Control: Nonlinear Elements and Educational Improvements." Diss., Available online, Georgia Institute of Technology, 2006, 2006. http://etd.gatech.edu/theses/available/etd-07072006-175615/.
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Thesis (Ph. D.)--Mechanical Engineering, Georgia Institute of Technology, 2007.William Singhose, Committee Chair ; Steven Danyluk, Committee Member ; Donna Llewellyn, Committee Member ; Nader Sadegh, Committee Member ; Neil Singer, Committee Member.
25
Peng, Chen-Chih. "Methods for improving crane performance and ease of use." Diss., Georgia Institute of Technology, 2013. http://hdl.handle.net/1853/50343.
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Cranes are widely used in material-handling and transportation applications, e.g. in shipyards, construction sites, and warehouses. As they are critical to the economic vitality of modern-day industries, improving crane performance and ease of use are important contributors to industrial productivity, low production costs, and workplace safety.
In a typical crane operation, a payload is lifted, moved to its destination, and then lowered into place. This dissertation aims to improve crane performance and reduce task difficulty for the human operator in the movements mentioned above, namely: 1) Moving payloads laterally in the horizontal plane, 2) Lifting payloads off the ground, and 3) Lowering or laying down payloads on the ground.
The design of a novel and intuitive human-machine control interface is the focus for improving operations that involve moving payloads laterally. The interface allows operators to drive a crane by simply moving a hand-held device through the desired path. The position of the device, which is tracked by sensors, is used to generate command signals to drive the crane. This command is then input-shaped such that payload oscillations are greatly reduced, making it much easier for the operator to drive the crane. Several facets of this crane control method are examined, such as control structure and stability, usability contexts, modes of operation, and quantitative measures (by means of human operator studies) of performance improvements over standard crane control interfaces.
Lifting up a payload can be difficult for the operator, if the hoist is not properly centered above the payload. In these potentially dangerous and costly ``off-centered" lifts, the payload may slide on the ground and/or oscillate in the air after it is hoisted. Newtonian and Coulomb friction models that focus on the stiction-sliding-separation contact dynamics are derived and experimentally verified to study off-centered lifts. Then, with the goal of aiding operators during lift operations, simple but practical, self-centering solutions are proposed and implemented.
Laying down or lowering a payload to the ground can also be challenging for operators in certain situations. For example, laying down a long, slender payload from a vertical orientation in the air, to a horizontal position on a flat surface. If the operator does not properly coordinate the motions of the crane in the vertical and horizontal directions simultaneously, then the potential hazards that may occur during these operations include: 1) slipping of the pivot about which the payload rotates, leading to sudden and dangerous payload movements; and 2) excessive hoist cable angles that lead to ``side-pull" problems. Newtonian and Coulomb friction models are derived to describe this lay-down scenario. The forces and motions experienced by the payload are then used to determine the motion trajectories that the crane and payload should follow to execute a successful lay-down maneuver.
Finally, a special chapter is included to address the oscillation control of systems that have on-off nonlinear actuators, such as cranes powered by relay-controlled circuits. Due to their simplicity, ruggedness, and long service life, this type of crane can be commonly found in older factories or in applications where precise motion control is not a strict requirement. However, controlling payload oscillations on this type of crane is challenging for two reasons: 1) Relays that can only be turned on or off allow for only limited control over the crane velocity; and 2) These cranes typically have nonlinear asymmetrical acceleration and deceleration properties. Methods are derived for determining the relay switch-times that move single-pendulum and double-pendulum payloads with low residual oscillations.
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Sorensen, Khalid Lief. "Operational Performance Enhancement of Human Operated Flexible Systems." Diss., Georgia Institute of Technology, 2008. http://hdl.handle.net/1853/24773.
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Recent decades have been witness to explosive leaps in manufacturing productivity. Advances in communication technology, computing speed, control theory, and sensing technology have been significant contributors toward the increased productivity and efficiency that industry has exhibited. The continued growth of technological equipment and engineering knowledge challenges engineers to fully utilize these advancements in more sophisticated and useful automation systems.
One such application involves enhancing bridge and gantry crane operation. These systems are used throughout the globe, and are critical aspects of industrial productivity. Consequently, improving the operational effectiveness of cranes can be extremely valuable.
Effective control of cranes can be largely attributed to two distinct, but related aspects crane manipulation: 1) the expertise of operators, which are responsible for issuing commands to the structures, and 2) the dynamic properties of cranes, which influence how the structures respond to issued commands. Accordingly, the operational efficiency of cranes can be influenced by changing both the way that operators issue commands to cranes, and also how the crane responds to issued commands.
This thesis is concerned with dynamic control theory of flexible machines, and human/machine interaction, especially as these areas relate to industrial crane control. In the area of dynamic control, this thesis investigates control strategies that are specifically suited for use on systems that possess common actuator nonlinearities, like saturation, rate limiting, dead-zone, backlash, and finite-state actuation. In the area of human/machine interaction, this thesis investigates the effects of different crane interface devices on the operational efficiency of cranes.
27
Pizarro, David Victor. "Pulse rate, pulse pattern, and onset distance effects on subject braking responses while using an auditory collision warning signal." Thesis, Virginia Tech, 1994. http://hdl.handle.net/10919/40655.
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Mehta, Urmish R. "Optimal control of a high speed overhead crane including hoisting." Ohio : Ohio University, 1992. http://www.ohiolink.edu/etd/view.cgi?ohiou1172863064.
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Potter, James Jackson. "Input-shaped manual control of helicopters with suspended loads." Diss., Georgia Institute of Technology, 2013. http://hdl.handle.net/1853/50342.
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A helicopter can be used to transport a load hanging from a suspension cable. This technique is frequently used in construction, firefighting, and disaster relief operations, among other applications. Unfortunately, the suspended load swings, which makes load positioning difficult and can degrade control of the helicopter. This dissertation investigates the use of input shaping (a command-filtering technique for reducing vibration) to mitigate the load swing problem. The investigation is conducted using two different, but complementary, approaches. One approach studies manual tracking tasks, where a human attempts to make a cursor follow an unpredictably moving target. The second approach studies horizontal repositioning maneuvers on small-scale helicopter systems, including a novel testbed that limits the helicopter and suspended load to move in a vertical plane. Both approaches are used to study how input shaping affects control of a flexible element (the suspended load) and a driven base (the helicopter). In manual tracking experiments, conventional input shapers somewhat degraded control of the driven base but greatly improved control of the flexible element. New input shapers were designed to improve load control without negatively affecting base control. A method for adjusting the vibration-limiting aggressiveness of any input shaper between unshaped and fully shaped was also developed. Next, horizontal repositioning maneuvers were performed on the helicopter testbed using a human-pilot-like feedback controller from the literature, with parameter values scaled to match the fast dynamics of the model helicopter. It was found that some input shapers reduced settling time and peak load swing when applied to Attitude Command or Translational Rate Command response types. When the load was used as a position reference instead of the helicopter, the system was unstable without input shaping, and adding input shaping to a Translational Rate Command was able to stabilize the load-positioning system. These results show the potential to improve the safety and efficiency of helicopter suspended load operations.
30
Engelbrecht, S. W. H. "The measurement of vertical and lateral forces on electric overhead cranes during operation." Thesis, 2015. http://hdl.handle.net/10539/16636.
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This dissertation is a practical investigation into the
magnitude of the vertical and lateral forces exerted,
by electric overhead travelling cranes, on their
supporting structures during operation.
The method of measuring the forces and the equipment
used for the actual measurements are discussed, as well
as the equipment used for the processing of the
recoided date.
The forces measured during the experiments, executed in
two stages namely controlled conditions and normal
operation, are discussed under the headings of vertical
forces due to the weight of the crane and lead handled,
and the lateral forces due to cross travel movement,
skewing of the crane and acceleration/deceleration of
the crane.
It is shown that the vertical misalignment of the
rails, together with the stiffness of the crane
structure, has a large influence on the magnitude of
the vertical forces.
Drive wheel slip, tested under controlled conditions on
two E-type cranes, proved to cause high lateral forces.
Comparisons are made with the existing Codes of
Practice as well as with the theoretical models
of crane behaviour.
31
Clark, David Dominic. "The crane problem : scheduling with sequence-dependent set-up and processing times." Thesis, 1998. http://hdl.handle.net/10539/22823.
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A research project submitted to the Faculty of Science, University of the
Witwatersrand, Johannesburg, in partial fulfillment of the requirements for the
degree of Master of Science.The problem of scheduling with sequence-dependent set-up times in a dynamic environment is investigated by studying how various dispatching rules perform when used to schedule two cranes. Motivated by a practical scheduling problem, the effect on production by delays due to the conflicts that result between cranes is examined. The problem is formalized, and it is shown that it can be classified as a problem of scheduling with both sequence-dependent set-up and processing times. The effectiveness of simple dispatching procedures that are used in machine scheduling and for the control of automated guided vehicles is studied, using a simulation of a crane aisle with jobs arriving dynamically. In addition, a dispatching rule, which explicitly uses information regarding the state of the second crane, is examined. The simulation results confirm the non-dominance of certain dispatching procedures, and show how performance is improved as the rules are provided more information regarding the state of the scheduling environment. It is shown that when there are sequence-dependent processing times, a scheduling heuristic that uses global information does significantly better than more commonly used local heuristics.
AC2017
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Weryk, Michael E. "Transformation of the artifact : adaptive reuse of the LaSalle Coke Tower in Montreal, Quebec." Thesis, 1998. http://hdl.handle.net/2429/7971.
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The LaSalle Coke Tower is an existing structure located on a fifty-five foot strip of land bordering the
south edge of the Lachine Canal and the north side of St. Patrick's St. (Montreal, Quebec). The railway
passes through the structure at its base. Built at the turn of the century, the crane was used to hoist coal
from barges to an elevated conveyor that carried it across the street to Cote-St.-Paul Gas Works. It is
approximately 15 storeys high (167'). The Lachine Canal serviced the cause of industry from its
completion in 1824 to the opening of the St. Lawrence Seaway in 1959 at which time industry slowly
began to abandon the Lachine Canal area.
The basic premise of the design project revolved around both preservation and development of Tour
LaSalle Coke (LaSalle Coke Tower). Regarding preservation, it was the state of abandonment that was to
be preserved, allowing for a sense of mobility, vagrant roving, free time, and liberty. Architectural
production within the abandoned site must respond to the rhythms and flows of the passing of time and
the loss of limits. The two principal components include a provision for discovery (architecture as a
heuristic device) and an archive component housing historical documents relevant to the tower and it's
surrounding context (the Lachine Canal).
The essence of the project was to develop this type of site without destroying its character and without
detracting from its historical significance. Careful consideration was essential to negotiate between
development and preservation. A broader interpretation of heritage preservation was necessary: moving
beyond the isolated monument to include territory which characterizes a particular place. In this instance
tire place consisted of the extreme linear space of the canal and its adjacent properties in addition to the
remnant architectural artifact of the tower. The state of abandonment is a part of the history of the site.
The provision for discovery is made through the use of stairs and an elevator, allowing visitors
uninhibited access to the tower. This provision allows for multiple levels of interaction with the artifact,
from the short visit to a more comprehensive survey of the object. The archive component is a smallscale
intervention thereby minimizing the impact of specialized components (or private spaces) which
limit the sense of mobility, vagrant roving, free time and liberty. For the same reason, the food service
and primary toilet facility is located 'off site' approximately 320 feet to the east. The goal was to retain
the basic features of the artifact while providing for a means of discovery and documentation of a
National Historic Landmark.