How to calculate the arc length, chord length and chord height of arc LED display?
Aug 11, 2021
The arc screen can calculate the steel structure and the area of the arc screen only when the arc length, chord length and chord height are known. The Royal display of the LED display manufacturer will introduce the calculation method of the arc screen in detail. How to calculate the arc length, chord length and chord height of arc LED display?
1. Measure the chord length, chord height and arc length.
Generally, the arc length is difficult to measure and the size difference is large, so the arc length and radius are calculated according to the chord height and chord length for verification. The difference can be within 10cm. If the difference is large, please measure and calculate repeatedly.
2. Chord height and chord length measurement method.
The straight-line distance between the two ends of the arc is the chord length, and the midpoint of the chord length to the midpoint of the arc line is the chord height (or: the midpoint of the chord length is perpendicular to the chord length, and the distance from the drawn line to the arc line is the chord height) the chord height and arc length of the arc screen
3. Calculate the arc length and radius according to the chord height and chord length of LED display screen.
Calculation idea: calculate the angle of the right triangle formed by the chord height and chord length according to the formula. Example:
① Set the chord height as B and the chord length as 2a, measure 2A = 200 and B = 60, and calculate the arc length and radius
② The side length of the triangle formed by chord height and chord length is a = 100 and B = 60. The calculation method of chord height and chord length
③ The side length of the triangle formed by the chord height and chord length is a = 100 B = 60. Calculate the C side length according to the Pythagorean theorem. The formula of Pythagorean theorem is a square + b square = C square, i.e. C = 116.62
④ Then, according to the trigonometric function formula sin ∠ a = A / C (∠ A is the diagonal of a), that is, sin ∠ a = 0.86, and then calculate the chord length and chord height angle of ∠ a = 59.32 ° with the anti sinusoidal function of the calculator
⑤ Extend edge B to the center of the circle, and connect the vertex of ∠ B to the center of the circle. Isosceles triangle is formed. The isosceles triangle ∠ C = 62 ° is obtained according to the internal angle of the triangle and 180 °, and the arc screen radian is calculated as 124 °
⑥ Then, according to the formula of sin ∠ C = C / beveled edge, sin62 = 100 / beveled edge is obtained, and the sin62 of the calculator is 0.883, that is, the length of the beveled edge is 113.3, r = 113.3, and the calculation method of the length of the beveled edge
⑦ The circumferential length of the arc is: perimeter = 2 π r = 2 * 3.14 * 113.3 = 711.52 perimeter / 360. The value of each angle of the circle is: 1.98 arc length = 1.98 per degree * 124 radian of billboard = 245.52.
The final result is arc length: 245.52 radian: 124 ° radius: 113.3 arc screen calculation method
4. Compare the calculated arc length of LED display with the actual measured arc length
The difference can be within 250px. If the difference is large, please measure and calculate repeatedly.
