A velocity based gait generation algorithm with real time adaptation rules which are necessary for steady walking is suggested. Particularly, we have developed a steady crawl gait with duty factor beta = 0.75. The main feature of the suggested algorithm is that it does not based on the foothold selection, and it can be used for the walking of blind robots on more realistic irregular terrain. The adaptation algorithms are the translational velocity modification to satisfy the steady gait requirement and the swing period modification to avoid the kinematic limitation. The suggested gait generation algorithm has been implemented in a simple quadruped robot which has totally eight actuated joints on the legs. Using the PD controller for the trajectory following and the adaptation algorithm of gait parameters, the steady periodic crawl gait on low irregular terrain has been demonstrated.