\(V_{i}^{k+1}=k_{g}\bullet V_{i}^{k}+k_{d}\bullet\text{rand}_{1}\bullet\frac{\left(X_{d}-X_{i}^{k}\right)}{t}+k_{g}\bullet\text{rand}_{2}\bullet\frac{\left(X_{g}-X_{i}^{k}\right)}{t}\) (11)