Robust Control Based on Suboptimal Estimator for Highly Nonlinear Robotic Arms Influenced Model Uncertainties and Environmental Disturbance Journal title: Aerospace Mechanics Authors: Akbar Asgharzadeh- Bonab,Naeim Yousefi Lademakhi,Hamid Bigdeli, Subject(s): Aerospace Engineering, Mechanics, Fluid Mechanics/Dynamics, Thermodynamics