The yo-yo ball rope extension test instrument makes the length measuring system( to calculate the elongation length) and the yo-yo ball installed in the same spindle for rotating.
When the yo-yo ball rotates at the speed 80r/min, the line of the ball will stretch along the centrifugal direction, and the test line(one end fixed in the ball, the other end fixed on the trolling reel) is connected with the encoder, the trolling reel and the spindle of the encoder are free state, and the bearing friction can be ignored.

The machine body can fixed on the wall through the fixed suport,or fix it on the floor.
The machine body can be installed on the wall through the fixed suport, or on the floor.

The test process is controlled by intelligent MCU, read the turns of the trolling reel through the encoder pulse, calculate the increment of each circle by considering the line of the reel increasing on the first circle. And improve the measurement accuracy value by taking multi-point to calculate.
Interface display: rotating speed, length, start/stop/reset. (digital display, page display the speed and length);
Length measuring system, DC motor with speed adjustment, intelligent MCU control.
Wall fixing suport or floor stand seat(adjustable)
Encoder and intelligent control signal transmission system
Rotating speed:1-150(adjustable)  
Stroke:0-1000MM(adjustable)
Standard: ASTM963-08