Performance Analysis and Technical Feasibility Assessment of a Transforming Roving-Rolling Explorer Rover for Mars Exploration

Abstract

This paper explores a two state rover concept called the Transforming Roving-Rolling Explorer (TRREx). The first state allows the rover to travel like a conventional 6-wheeled rover. The second state is a sphere to permit faster descent of steep inclines. Performance of this concept is compared to a traditional rocker-bogie (RB) architecture using hi-fidelity simulations in Webots. Results show that for missions involving very rugged terrain, or a considerable amount of downhill travel, the TRREx outperforms the rocker-bogie. Locomotion of the TRREx system using a continuous shifting of the center of mass through “actuated rolling” is also explored. A dynamics model for a cylindrical representation of the rover is simulated to identify feasible configurations capable of generating and maintaining continuous rolling motion even on sandy terrain. Results show that in sufficiently benign terrain gradual inclines can be traversed with actuated rolling. This model allows for increased exploration of the problem's design space and assists in establishing parameters for an Earth prototype.

Lateral Stability of a Mobile Robot Utilizing an Active Adjustable Suspension

“…By substituting Equations (13), (15), and (16) into Equation (14), solutions for lateral tip-over gradients are obtained employing the inputs, and , which are the lengths of downhill-side and uphill-side linear actuators, as variables.…”

“…In other words, the mobile robot can level its configuration when the slope angle is lower than 12.33°. The roll angle of the robot can be obtained using Equations (13), (15), and (16). As indicated in Figure 11b, when the slope angle is 5° or 10°, the roll angle of the robot decreases to 0°.…”

“…When the slope angle is 5°, increases from 39.78°to 40.22°(1.11%); when the slope angle is 10°, increases from 34.78° to 36.32°(4.43%); when the slope angle is 12°, increases from 32.78° to 34.91°(6.5%). The roll angle of the robot can be obtained using Equations (13), (15) and (16). As indicated in Figure 11b, when the slope angle is 5 • or 10 • , the roll angle of the robot decreases to 0 • .…”

“…Mobile robots with active suspensions can alter their structures and configurations to change their center of mass to avoid tipping over while traversing complicated unstructured terrains [1,2]. The Sample Return Rover [8], Scarab [9], ATHLETE [10], Tri-star [11], Sherpa [12], Workpartner [13], Azimut [14], TRREx [15,16], and Hylos [17] are examples. Additionally, Zheng et al proposed a wheel-step rover with a modified active rocker-bogie suspension that could use both wheeled and legged motions [18].…”

Multidisciplinary Design Optimization for a Solar-Powered Exploration Rover Considering the Restricted Power Requirement

“…Some studies have investigated the design and development for a novel type of the exploration rover that considers the obstacle-climbing capability and/or locomotion performance [17][18][19][20][21][22][23]. Several studies have also analyzed the effects of the wheel shape [24][25][26][27][28][29].…”