rigid body dynamics and simulation(刚体动力学仿真)
lagrange multiplier velocity based model (拉格朗日乘数速度模型)
Trinkle/Stewart and Anitescu/Potra
joint (关节点): ball, hinge, slider
first order integrator(一阶积分)
Contact and friction model: Dantzig LCP solver(丹泽尔线性补偿模型) by Baraff
Coloumb friction model(库伦摩擦，也称为干摩擦, 静摩擦)
ERP (error reduction parameter)
CFM(constraint force mixing)
square diagonal matrix(对角矩阵)
spring and damper constants(弹簧和阻尼约束器):
spring: kp dampler: kd , stepSize: h ---> ERP = hkp/(hkp + kd), CFM = 1/(hkp + kd)
friction coefficient 摩擦系数
Coulomb friction model : |fT | <= μ * |fN|
Degrees Of Freedom(自由度):
temporal coherence (时间相干性)
singularities(奇异性）
inertia (惯性）
