This paper proposes an approach of generating the gait pattern that Asian Institute of Technology's Leg EXoskeleton (ALEX) and its wearer can walk safely with the passing criteria of Zero Moment Point (ZMP) theorem for static and dynamic considerations, respectively. ALEX has 12 DOF (6 DOF for each leg: 3 at the Hip, 1 at the knee and 2 at the ankle), controlled by 12 DC motors. The CAD drawing and assembly of ALEX are exported directly to MATLAB's Simulink/SimMechanics simulation environment to assure accurate positioning of center of gravity (CG) and moment of inertia of each of the links that make up this 12 DOF robot. The gait pattern is visually observed in virtual environment (VR) using 3D VRML interpreter while ZMP trajectory is monitored using MATLAB's 2D graphics representation. With this developed simulation of ALEX, the robot can be tested to confirm its balance gait motion prior to the real implementation on the physical system that could cause serious damages to the robot itself and its fragile electronic devices.

This paper is the extension of gait pattern generation of the Asian Institute of Technology’s Leg EXoskeleton (ALEX) and its wearer can walk safety with the passing criteria of Zero Moment Point (ZMP) theorem for static and dynamic considerations respectively. ALEX has 12 DOF (6 DOF for each leg: 3 at the Hip, 1 at the knee and 2 at the ankle), controlled by 12 DC motors. The CAD drawing and assembly of ALEX are exported directly to MATLAB’s Simulink-SimMechanics to obtain accurate position of center of gravity (CG) and moment of inertia of each link. The gait pattern is visually observed using 3D VRML interpreter while ZMP trajectory is monitored using MATLAB’s 2D graphics representation. The further gaits generations in this paper include walking from non-zero initial condition, climbing up the stairs and turning left motions. From previous work, the gait data from simulation has confirmed it effectiveness with the actual hardware. With this further gait generation data, ALEX can be tested to confirm its balance gait motions prior to the real implementation to avoid any undesired motions that could damages to the robot system.