A Generation Step for Force Reflecting Control of a Pneumatic Excavator Based on Augmented Reality Environment

Nowadays, excavators play an important role in construction machinery. Among them, pneumatic excavators are suitable selections for some specific applications, because of their advantages. As a new trend, automation of excavation helps improving productivity, safety, and reducing of operation costs, consequently, making construction works become feasible even in hostile environment. In traditional auto-operating methods, excavators are controlled by joysticks through a so-called virtual environment in which the excavation performance is determined by some sensors attached to the real machines. However, the control accuracy by using these methodologies is reduced proportionally to the number of used sensors. The aim of this paper is to develop a mathematic model to apply to force reflecting control method based- augmented reality environment for a pneumatic excavator. Here, the mathematic model was constructed and optimized by practical excavation data. Once, the optimized model is obtained, it can be used in a combination with potential meters attached on the excavator to estimate loading forces without using any force sensor as well as to monitor current states of the excavator in the virtual environment. By using the estimated force to create a reflecting force to the joysticks, the driver can feel the real working conditions as directly-driving method. A mini-scaled pneumatic excavator was used in this study for investigating the proposed modeling method.