Improved Mobility in a Multi Degree of Freedom Unmanned Ground Vehicle

摘要

Mandelbrot through his analysis of Fractals (Mandelbrot 1977) has shown that the complexity of the physical geometry of nature is similar at all scales. This implies that a robot of fixed dimension will always be too big to get though some passageways and too small to get over some other obstacles However as others have demonstrated Increasing the number of the vehicle's motion degrees of freedom (dof) may permit it to change its conformation and dimensions, affording to it a greater range of environmental dimensionality through which it may move. This paper contains a description of our multi dof unmanned ground vehicle (UGV), including the variety of basic behaviors of which it is capable Our UGV is a six-dof sensor-rich small mobile robot composed of three segments - a central core and two tracked pods. The rotations of the pod tracks are the primary mobility mode (2-dof) of the vehicle. The pods are attached to the core at opposite ends, each by a single 'L' axle that rotates through l80 degrees (2-dof), serving to improve balance and leverage. The pods can rotate 360 degrees about their end of the axle (2-dof) providing increased mobility over obstacles The UGV in compact form is 17,6(inches) long 16,2(inches) wide, and 4, 6(inches) tall, but can extend to 49(inches) long to climb over obstacles or cross chasms, or rise to 16(inches) high to straddle low obstacles, In its extended mode its maximum width is 9,5(inches) permitting it to squeeze through an opening of that size, The UGV can independently draw in its two outer pods to grasp and longitudinally traverse horizontal pipes or logs or travel within a narrow culvert.