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	The MathWorks - MATLAB Digest - September 2002 - Creating a Stewart Platform Model Using SimMechanics
		The Stewart Platform design is also used for the positioning of satellite communication dishes and telescopes and in applications such as shipbuilding, bridge construction, transportation, and as a drilling platform on the Lunar Rover.
		The Stewart Platform can be used to position the platform in six degrees of freedom (three rotational degrees of freedom, as well as three translational degrees of freedom).
		Linear actuation of the Stewart Platform is accomplished by varying the lengths of the legs.
	www.mathworks.com /company/newsletters/digest/sept02/stewart.html (1339 words)

	Stewart platform -- Facts, Info, and Encyclopedia article (Site not responding. Last check: 2007-09-19)
		A Stewart platform is a kind of manipulator using an octahedral assembly of struts.
		Stewart platforms have applications in machine tool technology, crane technology, underwater research, air-to-sea rescue, flight simulation, satellite dish positioning and aircraft simulators.
		The Stewart platform was first reported in a paper by D. Stewart in 1965.
	www.absoluteastronomy.com /encyclopedia/s/st/stewart_platform.htm (107 words)

	[No title] (Site not responding. Last check: 2007-09-19)
		Stewart platform with fixed actuators relative to the heart and platform trajectory marked with ‘x’, (inverted view) In order to avoid singularities, a security margin of 15º between the platform and the legs is taken.
		Platform is observed in neutral position and at the end-point of the trajectory.
		Stewart Platform and base coordinate system (B), and platform coordinate system (P) A Stewart platform-type actuator (SP) immobile parts, base and platform, are uniquely defined by the coordinates of the six joints that connect them with legs.
	www.cs.columbia.edu /~laza/Projects/robot/sppaper2.doc (2297 words)

	Positional Control in Chemical Synthesis
		In its most basic form, the Stewart platform consists of an octahedron in which one triangular face is designated the "platform" and the opposing triangular face is designated the "base." The six struts of the octahedron that connect the base to the platform can be varied in length.
		The position and orientation of the shaft (which is analogous to the platform in the Stewart platform) is defined by the line segment between the tips of the two main struts.
		If we assume that the positional variance of the Stewart platform in any given direction is approximately equal to the positional variance of a single strut, then (7) also describes the approximate positional variance for the Stewart platform.
	www.zyvex.com /Research/Publications/articles/6dof.html (3812 words)

	[No title]
		One of the platforms is defined as the "movable platform," which has six degrees of freedom relative to the other platform, which is the "base." With six degrees of freedom, the movable platform is capable of moving in three linear directions and three angular directions singularly or in any combination.
		When the locations of the connection points of the prismatic legs are known for both platforms, and when the legs can be actuated and their length determined, then closed-loop control of the position and orientation of the movable platform relative to the base platform is possible, and depends on the solutions to two geometrical computations.
		A Stewart platform design that is based on an in-parallel structure lends itself well to static force analysis, particularly when utilizing the theory of screws.
	knut.kumoh.ac.kr /~tskim/platintro.html (1435 words)

	TITLE (Site not responding. Last check: 2007-09-19)
		The basic Inverted Stewart Platform (and the surrounding octahedral control frame) is a machine that uses non-orthogonal actuators (cables) to move and position objects smoothly, coordinate systems.
		The Inverted Stewart Platform consists of a work platform in the shape of an equilateral triangle that is suspended by six cables from an octahedral control frame.
		The cables (strings in my model) are attached to the vertices of the platform, run through pulleys attached to the upper vertices of the octahedral frame, and continued down to the base where they are attached to cranks which control the lengths of the cables.
	pilgrims.net /plymouth/schools/Science/scifair9/abstracts/engineering/en5.htm (265 words)

	[No title]
		Let the 9 coordinates of 3 non-collinear points from the mobile platform be chosen to represent its position and orientation in space.
		Stewart Platform stands for the same thing though the "real" Stewart Platform is only a particular case.
		In fact the direct kinematic model of a general Stewart platform may be reduced to the solution of a system of 6 quadratics and 3 linear equations in 9 unknowns.
	www.math.niu.edu /~rusin/known-math/98/stewart_plus (1380 words)

	ASL RESEARCH ISOLATION
		This Stewart platform is based on the cubic configuration whose legs consist in soft electro-dynamic actuators.
		The ULB six-axis isolator based on Stewart platform shown in Fig.1 is equipped with six voice coil actuators and six force sensors in the six legs.
		Although the stroke of the actuator does not exceed 55 mm the translation and rotation strokes of the upper platform are 90,103 and 95 mm in the x, y and z directions respectively and 1300, 1150 and 700 mrad around the x, y and z directions respectively.
	www.ulb.ac.be /scmero/isolation.html (1482 words)

	Stewart Platforms Development
		The platform can be used to position parts for an assembly operation, or when it is inversely mounted, as a tool post for metal removal operations on an NC machine.
		The overall size of the platform is expected to be contained within a space of 150 x150 x 150mm, and its operations within micron accuracy.
		However, due to the availability of the actuator in the market, the platform is finally designed in the space of 250 x 250 x 250 mm.
	serve.me.nus.edu.sg /ongsk/stewart.html (388 words)

	Craig's Musings > Entry > Stewart vows to increase spending (Updated)
		Stewart said that he plans to increase funding for public safety and the funding for law enforcement in the county had actually declined as a percentage of the General Fund portion of the budget in recent years.
		Stewart argues that this increase in spending is not enough and the county needs to spend more on public safety while cutting other areas to pay for the difference.
		Stewart never said that spending on Police had decreased -- he said it had decreased as a percentage of the budget, underlining his point that the County is losing its focus on core services..
	www.vitter.com /craigsmusings/entry.aspx?entry=499 (1069 words)

	A (Site not responding. Last check: 2007-09-19)
		A platform manipulator for the CABG surgery device would have to be able to move actuated surgical instruments and a camera, fast and precise enough to follow the heart movements and conform to safety requirements at the same ti me.
		The base and the platform are usually designed as an irregular hexagon positioned in the x-y plane and symmetric with respect to the y-axis as in the Figure 4.
		The output is the pose of the platform represented by the transformation m atrix R or the pose vector q.
	www.cs.columbia.edu /~laza/Stewart/thesis/METHODS.html (2004 words)

	plat_con (Site not responding. Last check: 2007-09-19)
		An inverted, ceiling-mounted Stewart platform design enables the use of narrower hydraulic cylinders than required with floor-mounted designs, and significantly reduces hydraulic flow requirements and hence the cost.
		The UBC Stewart platform simulator uses six 1.5 inch bore, 54 inch stroke hydraulic actuators each controlled in a three-way configuration.
		Based on the cylinder performance, the predicted platform acceleration with a payload of 250 Kg is of +- 1g, +- 400 degrees/s/s, at speeds exceeding +-1 m/s and +- 30 degrees/s.
	www.ece.ubc.ca /~tims/plat_con.html (215 words)

	ROBOOP, A Robotics Object Oriented Package in C++: Stewart Class Reference
		is the vector of the center of mass of the platform with reference to the local frame (platform).
		is the moment transferred from the platform to the link (not present is the spherical joint is at the platform end).
		J is the Jacobian matrix of the platform.
	www.cours.polymtl.ca /roboop/docs/html/classStewart.html (1078 words)

	Stewart outlines platform; looks at crime, police, business (Site not responding. Last check: 2007-09-19)
		Stewart unveiled his mayoral platform Tuesday, touting "a new era" for the city should he be elected.
		Stewart expects the campaign to cost at least $20,000 and, while it will be difficult, expects to "overthrow" Rabideau.
		Stewart said "taxes and tarmac" should be the standard for a mayor, not the exception.
	www.pressrepublican.com /Archive/1999/09_1999/090819994.htm (591 words)

	Description of the Architectures (Site not responding. Last check: 2007-09-19)
		2 (b), is similar to the first except that the location of the attachment points on the base and on the moving platform are not in a plane and are not symmetric.
		It was designed for use as a flight simulator motion-base, and was intended to have a larger workspace than a Stewart platform with legs of similar length.
		The six legs connecting the base to the moving platform are of the PHS type rather than the HPS type--where H, P and S respectively denote Hooke, prismatic and spherical joints.
	wwwrobot.gmc.ulaval.ca /~ricard/Articles/Delft_ceas_95/node2.html (507 words)

	Speakers Platform Speakers Bureau: Dave Stewart, Keynote Speaker On: Athletics/Sports, Achievement/Peak Performance
		David Keith Stewart (born February 19, 1957 in Oakland, California) is a former right-handed starting pitcher in Major League Baseball during the late 1980s and early 1990s.
		Stewart was drafted by the Los Angeles Dodgers in the 16th round of the 1975 amateur draft and made his major league debut on September 22, 1978.
		Stewart was also a part of the 1992 Oakland Athletics team which lost in the ALCS to the Toronto Blue Jays.
	www.speaking.com /speakers/davestewart.html (558 words)

	TITLE (Site not responding. Last check: 2007-09-19)
		The basic Inverted Stewart Platform (and the surrounding octahedral control frame) is a machine that uses non-orthogonal actuators (cables) to move and position objects smoothly, coordinate systems.
		The Inverted Stewart Platform consists of a work platform in the shape of an equilateral triangle that is suspended by six cables from an octahedral control frame.
		The cables (strings in my model) are attached to the vertices of the platform, run through pulleys attached to the upper vertices of the octahedral frame, and continued down to the base where they are attached to cranks which control the lengths of the cables.
	www.plymouthschools.com /Science/scifair9/abstracts/engineering/en5.htm (265 words)

	Description of the architectures (Site not responding. Last check: 2007-09-19)
		1 (a), and is commonly referred to as a Stewart platform (Stewart 1965; Pittens and Podhorodeski 1993).
		1 (b), is similar to the first except that the location of the attachment points on the base and on the moving platform are not in a plane and are not symmetric.
		Indeed, the 6 kinematic chains connecting the base to the moving platform are of the PHS type rather than the HPS type--where H, P and S respectively denote Hooke, prismatic and spherical joints.
	wwwrobot.gmc.ulaval.ca /~ricard/Articles/Boston_asme_95/node2.html (496 words)

	Method and apparatus for controlling geometrically simple parallel mechanisms with distinctive connections (US5179525)
		The dimensions of the base platform and the movable platform, as well the lengths of the support legs, are provided to a control system.
		The control system is suitable for controlling known 3-3 or 6-3 Stewart platforms in a novel manner, as well as controlling the novel special 6-6 parallel mechanism.
		Also disclosed is a method for reducing the novel special 6-6 parallel mechanism to a Stewart platform equivalent, which is then controlled by the disclosed closed-form forward displacement control system.
	www.delphion.com /details?pn=US05179525__ (544 words)

	Nanotechnology Timeline (Site not responding. Last check: 2007-09-19)
		By the year 2000, there will be a Stewart platform, made to atomic specifications, fitting in a one micron cube, able perform 1,000 6-degree-of-freedom operations per second.
		Z-axis motion was sufficient for this application (for a total of only 4 dofs for the Stewart platform component), but may not be for the nanomech-l application.
		Since the reagent-binding tool of the nanomech-l reference system is on the top (outside) of the platform (see _Nanosystems_ figures 16-4,5), the extra dofs need to be added by moving the whole platform, which complicates the power linkage, and increases cycle time (since more mass would have to be moved than previously thought).
	www.lucifer.com /~sean/N-FX/axis.html (440 words)

	Forward Kinematics and its Need for Control and Measurement (Site not responding. Last check: 2007-09-19)
		Beacuse of the Stewart platform closed kinematic chain, the rigidity of the end effector, and the accuracy of the link length servos, a reasonably accurate feed-forward assignment is possible.
		These are the cases when the Stewart platform is used as a component of a measuring device.
		In Figure 5, the RST triangle is the fixed platform and the ABC triangle is the moving platform.
	www.ee.umd.edu /medlab/papers/robautforsem97/node2.html (628 words)

	Stephen Hagberg - UF Journal of Undergraduate Research Paper
		Using a device based on a six-degree of freedom Stewart platform or hexapod geometry, a proof of concept device was constructed to determine if such an approach can prove to be a cost effective way of solving the problem.
		Of particular interest is a device commonly referred to as a “Stewart Platform” or hexapod which creates six-degree of freedom motion of a platform by varying the lengths of the six legs or struts which support it thereby allowing it to tilt and move in various directions [3].
		Consider the movable platform to be a simple beam allowed to pivot at one end with the other connected by a spherical joint to a leg of fixed length which connects to the actuator (figure 2).
	www.clas.ufl.edu /jur/200310/papers/paper_hagberg.html (2085 words)

	9.3.1.5
		The Stewart platform exploits the geometry of an octahedron -- one triangular face serves as a mobile platform and the opposing triangular face serves as the fixed base.
		Six struts of the octahedron connect the base to the platform and can be varied in length, thus controlling platform position and orientation with respect to the base.
		In the earliest, most primitive Stewart platform type nanomanipulators operating in aqueous suspension, R. Merkle suggests that leg extension and retraction may be controlled by manufacturing the legs using a repeating sequence of binding sites on the surfaces of two opposing struts.
	www.nanomedicine.com /NMI/9.3.1.5.htm (319 words)

	Task Planner (StepCost) (Site not responding. Last check: 2007-09-19)
		It is believed that research in parallel robots such as Stewart platform should be focused more on how the robots perform a task when they are executing motions in physical space.
		Given a series of the motion sequences of a component that are specified, optimize the paths and motion of all the Stewart platforms that are manipulating the component while satisfying velocity and acceleration limits of each of the Stewart platforms.
		As shown in the left figure, the maximum velocity of a leg is 407mm/s for a distance d and angle a traveled by the moving platform of a Stewart platform in 8 second.
	www.warwick.ac.uk /fac/sci/Eng/AMG/flextool/software (800 words)

	Hexapod
		The report introduces the conventional Stewart platform and other new designs that are based on the same idea, in addition to calculation of the DOF for these designs.
		The output piece is defined as the movable platform which has six degree of freedom relative to the other platform, which is the base.
		The basic Stewart Platform is made up of six extensible struts, opposing to the previous design, with only one DOF (the cross section is non-circular, does not allow rotation).
	biotsavart.tripod.com /hexapod.htm (3310 words)

	Supercomputing Online - Homepage for the World’s High-Performance Computing, Networking & Storage Professionals
		STEWART: The agreement between SGI and Platform positions the two companies to better serve customers in the creation and enhancement of Grids.
		STEWART: Customers with a need for robust functionality on the Grid will benefit from a single point of contact for the two companies in the creation of their grid environments.
		The projects SGI and Platform work together on will be focused on the provision of computation for furthering the research and practice within diverse disciplines in contrast with those grid projects which exist to research the computational science of the Grid.
	www.supercomputingonline.com /article.php?sid=2310 (998 words)

	MotionSimulation_April2000
		The forces on the rider are the sum of gravity and the platform accelerations.
		Motion Platforms are often characterized by the range of motion, load capacity, degrees of freedom (DOF), and types of actuators used to move the platform.
		The platform is a chair designed to fit in a relatively small space, allow modular component replacement, and provide low cost, easy construction and maintenance.
	www.isdale.com /jerry/VR/vrTechReviews/MotionSimulation_April2000.htm (1319 words)

	Manf. Education:Alternative Machine Tool Structure Pages(5) (Site not responding. Last check: 2007-09-19)
		A Stewart Platform basically consists of a base (lower platform) and end effector (top platform) connected by six actuator driven legs.
		In order to change the position of the top platform relative to the bottom platform all the six legs move in a coordinated direction and produce the desired displacement.
		The most general Stewart platform is the 6-6 platform, where the legs connect to six different points on the base and six different point on the top platform.
	www.mfg.mtu.edu /cyberman/machtool/machtool/altstruc/res5.html (377 words)

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