Considering a soft robot with installed bounded actuators, this paper studies the reachable workspace estimation problem for a pre-chosen point of interest. To this aim, the method of nite-element has been used to obtain the static model of the studied robot and two methods are proposed (forward one which is based on Newton iterative method and forward-backward one which is based on interval analysis techniques) to study this estimation problem. Various simulations with dierent conguration scenarios are provided to show the eectiveness of the forward-backward approach which can largely reduce the exploration time, compared to the forward method.