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Ellipsograph
A trammel of Archimedes is a mechanism that generates the shape of an ellipse. () It consists of two shuttles which are confined ("trammeled") to perpendicular channels or rails and a rod which is attached to the shuttles by pivots at fixed positions along the rod. As the shuttles move back and forth, each along its channel, all points on the rod move in elliptical paths. The motion of the rod is termed elliptical motion. The semi-axes ''a'' and ''b'' of the ellipses have lengths equal to the distances from the point on the rod to each of the two pivots. The straight lines described by the pivots are special cases of an ellipse, where the length of one axis is twice the distance between the pivots and that of the other is zero. All points on a circle with a diameter defined by the two pivots reciprocate in such straight lines. This circle corresponds to the smaller circle in a Tusi couple. The point midway between the pivots orbits in a circle around the point where the chann ...
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Ellipsograph
A trammel of Archimedes is a mechanism that generates the shape of an ellipse. () It consists of two shuttles which are confined ("trammeled") to perpendicular channels or rails and a rod which is attached to the shuttles by pivots at fixed positions along the rod. As the shuttles move back and forth, each along its channel, all points on the rod move in elliptical paths. The motion of the rod is termed elliptical motion. The semi-axes ''a'' and ''b'' of the ellipses have lengths equal to the distances from the point on the rod to each of the two pivots. The straight lines described by the pivots are special cases of an ellipse, where the length of one axis is twice the distance between the pivots and that of the other is zero. All points on a circle with a diameter defined by the two pivots reciprocate in such straight lines. This circle corresponds to the smaller circle in a Tusi couple. The point midway between the pivots orbits in a circle around the point where the chann ...
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Bullshit Grinder
A trammel of Archimedes is a mechanism that generates the shape of an ellipse. () It consists of two shuttles which are confined ("trammeled") to perpendicular channels or rails and a rod which is attached to the shuttles by pivots at fixed positions along the rod. As the shuttles move back and forth, each along its channel, all points on the rod move in elliptical paths. The motion of the rod is termed elliptical motion. The semi-axes ''a'' and ''b'' of the ellipses have lengths equal to the distances from the point on the rod to each of the two pivots. The straight lines described by the pivots are special cases of an ellipse, where the length of one axis is twice the distance between the pivots and that of the other is zero. All points on a circle with a diameter defined by the two pivots reciprocate in such straight lines. This circle corresponds to the smaller circle in a Tusi couple. The point midway between the pivots orbits in a circle around the point where the chan ...
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Ellipse
In mathematics, an ellipse is a plane curve surrounding two focus (geometry), focal points, such that for all points on the curve, the sum of the two distances to the focal points is a constant. It generalizes a circle, which is the special type of ellipse in which the two focal points are the same. The elongation of an ellipse is measured by its eccentricity (mathematics), eccentricity e, a number ranging from e = 0 (the Limiting case (mathematics), limiting case of a circle) to e = 1 (the limiting case of infinite elongation, no longer an ellipse but a parabola). An ellipse has a simple algebraic solution for its area, but only approximations for its perimeter (also known as circumference), for which integration is required to obtain an exact solution. Analytic geometry, Analytically, the equation of a standard ellipse centered at the origin with width 2a and height 2b is: : \frac+\frac = 1 . Assuming a \ge b, the foci are (\pm c, 0) for c = \sqrt. The standard parametric e ...
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Ellipse Compass-MHS 614-IMG 3827-gradient
In mathematics, an ellipse is a plane curve surrounding two focal points, such that for all points on the curve, the sum of the two distances to the focal points is a constant. It generalizes a circle, which is the special type of ellipse in which the two focal points are the same. The elongation of an ellipse is measured by its eccentricity e, a number ranging from e = 0 (the limiting case of a circle) to e = 1 (the limiting case of infinite elongation, no longer an ellipse but a parabola). An ellipse has a simple algebraic solution for its area, but only approximations for its perimeter (also known as circumference), for which integration is required to obtain an exact solution. Analytically, the equation of a standard ellipse centered at the origin with width 2a and height 2b is: : \frac+\frac = 1 . Assuming a \ge b, the foci are (\pm c, 0) for c = \sqrt. The standard parametric equation is: : (x,y) = (a\cos(t),b\sin(t)) \quad \text \quad 0\leq t\leq 2\pi. Ellipses ar ...
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John Farey Jr
John Farey Jr. (20 March 1791 – 17 July 1851) was an English mechanical engineering, consulting engineer and patent agent, known for his pioneering contributions in the field of mechanical engineering.Alec Skempton.Farey, Jr., John" in: ''A Biographical Dictionary of Civil Engineers in Great Britain and Ireland: 1500–1830.'' 2002. p. 223-224 As consulting engineer Farey worked for many well-known inventors of the later Industrial Revolution, and was a witness to a number of parliamentary enquiries, inquests and court cases, and on occasion acted as an arbitrator. He was polymathic in his interests and contributed text and drawings to a number of periodicals and encyclopaedias. Farey is also remembered as the first English inventor of the ellipsograph, an instrument used by draughtsmen to inscribe ellipses. Biography Youth and education Farey was the eldest son of John Farey Sr. (1766–1826), the geologist, and Sophia Hubert (1770–1830). He was the older brother of J ...
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Hypotrochoid
In geometry, a hypotrochoid is a roulette traced by a point attached to a circle of radius rolling around the inside of a fixed circle of radius , where the point is a distance from the center of the interior circle. The parametric equations for a hypotrochoid are: :\begin & x (\theta) = (R - r)\cos\theta + d\cos\left(\theta\right) \\ & y (\theta) = (R - r)\sin\theta - d\sin\left(\theta\right) \end where is the angle formed by the horizontal and the center of the rolling circle (these are not polar equations because is not the polar angle). When measured in radian, takes values from 0 to 2 \pi \times \tfrac (where is least common multiple). Special cases include the hypocycloid with and the ellipse with and . The eccentricity of the ellipse is :e=\frac becoming 1 when d=r (see Tusi couple). The classic Spirograph toy traces out hypotrochoid and epitrochoid curves. Hypotrochoids describe the support of the eigenvalues of some random matrices with cyclic correlation ...
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Beam Compass
A beam compass is a compass with a beam and sliding sockets or cursors for drawing and dividing circles larger than those made by a regular pair of compasses. The instrument can be as a whole, or made on the spot with individual sockets (called trammel points) and any suitable beam. Draftsman's beam compass A draftsman's beam compass consists of a set of points and holders, mounted on a plated brass, aluminum, or German 'silver' rod. One end is generally locked down at the end of the rod, while the other has both rough and fine adjustments, though some are opposite in construction. The locked tip holder consists of a needle, for the centre of the radius, and the other holds either a lead clutch, or an inking nib. There are older variants which use a wooden beam. Another similar type is a Machinist or Engineers beam compass, which uses scribing points only, similar to ones used by woodworkers, except that its fine adjustment is generally more refined. These beam compasses can ...
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Bourke Engine
The Bourke engine was an attempt by Russell Bourke, in the 1920s, to improve the two-stroke internal combustion engine. Despite finishing his design and building several working engines, the onset of World War II, lack of test results, and the poor health of his wife compounded to prevent his engine from ever coming successfully to market. The main claimed virtues of the design are that it has only two moving parts, is lightweight, has two power pulses per revolution, and does not need oil mixed into the fuel. The Bourke engine is basically a two-stroke design, with one horizontally opposed piston assembly using two pistons that move in the same direction at the same time, so that their operations are 180 degrees out of phase. The pistons are connected to a Scotch Yoke mechanism in place of the more usual crankshaft mechanism, thus the piston acceleration is perfectly sinusoidal. This causes the pistons to spend more time at top dead center than conventional engines. The incom ...
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Hypocycloid
In geometry, a hypocycloid is a special plane curve generated by the trace of a fixed point on a small circle that rolls within a larger circle. As the radius of the larger circle is increased, the hypocycloid becomes more like the cycloid created by rolling a circle on a line. Properties If the smaller circle has radius , and the larger circle has radius , then the parametric equations for the curve can be given by either: :\begin & x (\theta) = (R - r) \cos \theta + r \cos \left(\frac \theta \right) \\ & y (\theta) = (R - r) \sin \theta - r \sin \left( \frac \theta \right) \end or: :\begin & x (\theta) = r (k - 1) \cos \theta + r \cos \left( (k - 1) \theta \right) \\ & y (\theta) = r (k - 1) \sin \theta - r \sin \left( (k - 1) \theta \right) \end If is an integer, then the curve is closed, and has Cusp (singularity), cusps (i.e., sharp corners, where the curve is not Differentiable function, differentiable). Specially for the curve is a straight line and the circles are ...
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Trammel Of Archimedes Small White
Trammel or Trammelsor Trammell may refer to: Places * Trammel, Virginia * Trammels, Texas, United States People with the name * Allen Trammell (born 1942), American football player * Joel Trammell (born 1965), American businessman * Trammell, both a surname and a given name Other uses * Trammel (fishing net) * Trammel, a tool for restraining a horse's ambling * Trammel hook * Trammel of Archimedes, a tool for drawing ellipses * Trammel points or trammels, metal points with clamping apparatus used to construct a beam compass A beam compass is a compass with a beam and sliding sockets or cursors for drawing and dividing circles larger than those made by a regular pair of compasses. The instrument can be as a whole, or made on the spot with individual sockets (called ... * '' Trammel v. United States'' {{disambiguation ...
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Useless Machine
A useless machine or useless box is a device which has a function but its direct purpose is deliberately unknown. The best-known useless machines are those inspired by Marvin Minsky's design, in which the device's sole function is to switch itself off by operating its own "off" switch. Such machines were popularised commercially in the 1960s, sold as an amusing engineering hack (term), hack, or as a joke. More elaborate devices and some novelty toy, novelty toys, which have a more obvious function or entertainment value, have been based on these simple useless machines. History The Italian artist Bruno Munari began building "useless machines" (''macchine inutili'') in the 1930s. He was a "third generation" Futurist and did not share the first generation's boundless enthusiasm for technology, but sought to counter the threats of a world under machine rule by building machines that were artistic and unproductive. The version of the useless machine that became famous in informatio ...
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Proclus
Proclus Lycius (; 8 February 412 – 17 April 485), called Proclus the Successor ( grc-gre, Πρόκλος ὁ Διάδοχος, ''Próklos ho Diádokhos''), was a Greek Neoplatonist philosopher, one of the last major classical philosophers of late antiquity. He set forth one of the most elaborate and fully developed systems of Neoplatonism and, through later interpreters and translators, exerted an influence on Byzantine philosophy, Early Islamic philosophy, and Scholastic philosophy. Biography The primary source for the life of Proclus is the eulogy ''Proclus, or On Happiness'' that was written for him upon his death by his successor, Marinus, Marinus' biography set out to prove that Proclus reached the peak of virtue and attained eudaimonia. There are also a few details about the time in which he lived in the similarly structured ''Life of Isidore'' written by the philosopher Damascius in the following century. According to Marinus, Proclus was born in 412 AD in Cons ...
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