Taxonomy, systems review and performance metrics of planetary exploration rovers

Abstract

Abstract-A taxonomy of planetary exploration rovers is presented, followed by a review of systems used in missions and in an experimental phase. The baseline design emerges as four or six wheels, rocker-bogie based passive suspension and all wheel driving / selected wheel steering. A trend is also apparent in the use of wheel -legged hybrid locomotion. The performance metrics are presented by which the differing configurations of the locomotion subsystem for wheeled rovers with a passive suspension may be systematically evaluated. The taxonomy and aggregated metrics presented in this paper aid in the comparison and selection of rover characteristics, while the baseline design is a representative example of current practices and future trends.

Theoretical study on a modified rocker-bogie suspension for robotic rovers

“…At the same time, to avoid the rear wheels slippage, the pushing forces magnitudes must be lower than the corresponding grip limit: (11) With reference to Fig. 12, indicating with h the bogie height and with L the horizontal distance between wheel C axis and hinge E when the three wheels are at the same level, from the static equilibrium condition, the rover external and internal reactions can be evaluated: rocker equilibrium:…”

“…The dimensions of the wheels and the lengths of the suspension links are chosen according to the dimensions of the obstacles to be overcome [10] and the mission characteristics [11]; the length of the links can also be chosen so that the vertical load is equally distributed among the wheels when the rover is on a flat horizontal surface; in this way, the pressure on the ground, the sinking, and the driving capacity are quite the same for all the wheels. However, due to the ground unevenness or to a different payload position, the load distribution may be altered.…”

A Comparison of Forward and Inverse Simulation Methods for Fault Detection on a Rover

“…In this particular case, the rover being modelled is a simple four-wheel drive rover with a fixed chassis and no suspension, that uses electric motors to drive the wheels and turns using a method called slip-steering (also known as skid or differential steering) [4]. This has been selected as it possesses a number of characteristics consistent with commonly used technologies on PERs [5].…”

Numerical stability of inverse simulation algorithms applied to planetary rover navigation

“…The distance and time to travel between each waypoint is calculated assuming a constant velocity between stages with initial and final acceleration and deceleration transients: the constant forward speed is 0.1 m/s, analogous to that of operating rovers [5], and the rotational velocity is 0.1 rad/s. At each waypoint a check is made to determine if the rover is at the correct angle for the next traversal forward.…”

“…To extract the maximum scientific return, the rover must be able to efficiently and safely navigate the terrain. The navigation capabilities are essential to the overall success of the mission [4], [5] and Inverse Simulation addresses this particular issue.…”