You need the positions of the sphere and the (don't know the right name) vessel (you used the positions of the green zero).
The main forces: gravitation and friction, ... lead to acceleration, deceleration -> different velocities -> changes of positions.
It doesn't matter if you can't track the ball positions for parts of the pictures.
Once ( few years ago) I asked the member: General for the differential equations, he posted kindly a pdf ( I already knew) somewhere in this board.
If you post postions of the ball and the green zero we can do some math work, as far as my time allows.
Here is some capture with my old detector :
[834.11, 396.78, 814.41, 329.43, 779.55, 269.23, 733.06, 216.14, 676.8, 170.67, 612.95, 138.08, 540.93, 115.72, 467.1, 103.52, 391.62, 104.17, 317.16, 116.66, 244.01, 141.85, 178.09, 178.63, 120.99, 226.36, 74.63, 284.65, 42.74, 350.74, 27.62, 424.43, 33.71, 499.83, 832.38, 485.24, 835.9, 421.21, 824.8, 359.21, 801.08, 301.84, 765.84, 250.49, 721.19, 204.67, 668.61, 166.19],[220.34, 311.78, 231.86, 300.91, 242.63, 289.8, 254.72, 280.28, 267.69, 271.25, 281.74, 262.42, 295.46, 255.29, 309.98, 248.51, 324.63, 242.62, 340.85, 236.89, 356.53, 232.34, 372.36, 228.86, 388.53, 226.06, 404.54, 223.74, 421.85, 223.33, 440.68, 222.93, 458.43, 223.38, 645.3, 310.1, 655.1, 322.53, 665.16, 334.36, 673.33, 348.03, 681.67, 361.62, 686.51, 376.02, 691.85, 390.81]
[834.89, 406.56, 819.36, 341.73, 790.44, 282.64, 747.91, 230.2, 696.3, 185.85, 635.97, 149.11, 571.57, 123.46, 501.38, 107.34, 429.2, 102.89, 356.48, 108.59, 285.46, 126.19, 218.71, 153.72, 158.56, 192.69, 105.43, 242.18, 65.8, 299.17, 38.36, 363.25, 27.46, 434.05, 34.97, 506.32, 824.49, 515.8, 824.49, 515.8, 835.33, 454.61, 834.35, 395.37, 816.75, 336.73, 790.72, 283.26], [643.83, 585.13, 632.05, 597.45, 618.3, 609.02, 604.18, 619.45, 589.59, 628.65, 574.19, 638.01, 557.36, 645.56, 540.67, 652.19, 523.36, 658.63, 506.04, 663.17, 487.4, 666.14, 466.24, 668.43, 447.09, 668.9, 426.56, 669.89, 406.53, 668.47, 387.2, 666.67, 368.89, 664.23, 350.47, 659.64, 184.18, 525.96, 184.18, 525.96, 179.1, 510.85, 174.22, 495.47, 171.18, 481.27, 169.71, 466.27]
[834.4, 399.32, 816.77, 336.69, 787.8, 279.73, 746.93, 229.53, 697.13, 186.07, 640.87, 151.82, 577.77, 125.33, 510.81, 108.72, 440.98, 102.65, 372.07, 105.94, 302.53, 120.84, 237.83, 144.7, 176.96, 179.51, 124.29, 222.9, 80.59, 274.94, 48.99, 334.11, 31.06, 397.45, 29.56, 466.79, 44.27, 536.29, 834.25, 466.73, 835.57, 409.32, 823.32, 353.33, 799.63, 299.88, 767.57, 252.6], [691.16, 503.42, 685.09, 520.14, 677.33, 536.27, 669.07, 552.2, 658.45, 567.61, 646.41, 582.22, 633.91, 596.1, 618.12, 608.89, 602.16, 620.88, 586.82, 631.08, 567.43, 641.13, 549.21, 649.59, 530.22, 655.5, 509.37, 662.56, 489.69, 666.26, 465.69, 668.09, 444.74, 668.8, 420.8, 669.85, 398.47, 667.52, 183.82, 523.64, 178.23, 506.43, 172.32, 490.57, 170.84, 472.56, 169.61, 455.29]
[BallX,BallY....],[ZeroX,ZeroY]
Detection will occur only when ball and zero are on screen (wich is not the case in the current version)
I can update my current version and re add the ball position if you want, from the launch to 128 tick records
Screen capture size is 864x864 pixels for information
Thanks !