Question

Dynamic Calculation, I am checking against a chart that give the max torque, due to Moment of inertia affect on a winding barrel, the cable wraps around barrel as a spiral .
The driving force is the mass hanging increases as it drops down and the lever arm reduces, the barrel intertia changes ( reduces ), and the barrel speed increases to a point at which the brake engages, I have written the code to work all of the mechanical dimension, but need to check the affect of a brake being suddenly applied, the brake stops the barrel in lets say 0.0895 sec , r= 0.1996 m :activation of brake at 58.54 RPM
I am applying 3 torques,

t1 = barrel inertia x rad/s2 : 7.8198 kg-metre^2 x 64.497 rad/s2 = 504 Nm

t2 = the amount of mass hanging down acting on the lever arm by the use of the linear speed m/s2 = t2 = 13.671 m/s2 x 55.11 kg x r = 150 Nm

t3 = mass x 9.81 x r = 55.11 kg x 9.81 x 0.1996 m = 107.9 Nm

q1 as the only driving force to spin the barrel is is derived from t3 and it is dropping down should I be allow some of the mass to change due to the speed of the drop, it's only resistance being the Moment of inertia to spin the barrel up to speed.

q2 am I dealing with the dynamics correctly asuming no friction or windage and that my figures look correct.

t =0.0895 sec

Bob