Mechatronic Design of a Mixed Conventional/Braking Actuation Mobile Robot

Abstract

This paper presents the design of a novel mixed conventional/braking actuation mobile robot (MAMR), which replaces conventional actuators used for steering with controllable brakes. The mechatronic design of a novel electromechanical braking actuator, its implementation in the MAMR, and the mechatronic design of the MAMR are presented. A motion experiment is also given as a demonstration. The MAMR presented in this paper implements a new platform for mobile robots which is composed of two electromechanical braking actuators and an omni-directional drive wheel. The electromechanical brake presented is an omni-directional ball transfer that is electronically lockable. When the brake is in the locked state, it generates a reactive friction force onto a dynamic system that, in the case of the MAMR, can be used to steer and brake. This platform offers a minimalistic approach to locomotion in mobile robots.

Nonlinear control synthesis for parking control of mixed conventional/braking actuation mobile robots

“…To park the robot at the target configuration, we design the sliding surfaces given by (17) and (19) from the initial configuration, and then switch between the reaching and sliding modes of the SMC. Note that some initial configurations may not need the two sliding surfaces to achieve the objective.…”

“…which provesṠ 1 (θ) = 0 for any driving force (F d ) and hence the trajectory, once on the sliding surface, stays on the surface for all driving forces all the time under the assumption that the brakes will not saturate. The same derivation also applies for the second sliding surface given by (19).…”

“…An additional advantage of this platform is that it can be configured for a variety of environments based on the design and type of the braking actuator. For example, Simmons et al [19] presented a prototype of the MAMR that uses a ball-type caster as a braking actuator. Improving on the design presented in [19], Nikshi et al [15] presented a prototype of the MAMR that uses brakes with conventional wheels to improve the coefficient of friction and reduce the mechanical complexity due to using an omni-directional ball-type caster.…”

“…To solve such problems in mobile robotics, the authors in [15,[18][19][20] proposed a new actuation approach that uses a mixture of conventional and braking actuation systems. This approach results in a new mobile robotic platform called the Mixed conventional/braking Actuation Mobile Robot (MAMR).…”

Parking Control of Mixed Conventional/Braking Actuation Mobile Robots Using Fuzzy Logic Control

“…Fuzzy control was chosen as the control methodology for its ability to deal with model uncertainties and inaccuracies through expert knowledge, e.g., those that arise from uncertain friction models [27]. Robles et al could manage the uncertainaty in controller performance using type-2 fuzzy logic approach In the current work we extend our previous work [32,33] in two distinct ways: 1) the design and control of a new braking actuation system that places nonholonomic constraints on the MAMR dynamics (useful for physical realization and control of the system) and 2) through validation of the FLC experimentally via physical implementation as opposed to pure simulation.…”