I have a heavy door that im adding torsion springs too in order to make it easier for a human to open. -The door weighs 460lbs. -It is hinged on one side by two heavy duty hinges and uses a thrust bearing in each hinge with a friction coef. of .008 -the effective radius of the thrust bearing is 31/32" -The door handle is 56" from the hinge -The torsion spring will apply its force 0.75" from the hinge. Id like to beable to pull with only 5lbf normal to the door at the door handle. I should beable to open the door 90* in 4 seconds Do i have enough information to estimate the amount of force needed from the torsion spring? If so, where do i start?? thanks in advance for your help.