19 accepted papers
Autonomous Mobile Robots are typically limited to structured environments, as conventional wheeled propulsion often fails on deformable terrains like sand due to excessive wheel slip and sinkage. To address this mobility challenge, this paper introduces a novel locomotion strategy for a high-degree-…
6-DoF posture estimation is a critical technique in robotics. However, a significant gap exists between the two primary approaches—camera-based methods and laser tracker systems—in terms of cost and performance. To bridge this gap, this work proposes a method to calculate the 6-DoF posture of a mani…
This paper presents the design, modeling, and experimental validation of a novel leg-wheel mechanism featuring an integrated, passive angle-bisecting foot. The core of the design is a two-stage planetary gear system. This system mechanically ensures a consistent foot-ground contact angle, addressing…
Hybrid leg-wheel robots offer exceptional mobility, but their complex mechanics and extended contact surfaces challenge modern control frameworks that rely on simple point-foot models. Accurately estimating both the contact state and the precise contact location using only proprioceptive sensors is …
Accurate estimation of contact forces is crucial for effective control of quadrupedal robots, especially in complex locomotion scenarios. In this paper, we introduce a novel force estimation technique for robots equipped with transformable leg-wheels. Unlike conventional methods that focus on forces
This paper introduces an noval autonomous mobile robot, IOMT, designed for indoor and outdoor multi-terrain environments, with a particular focus on stair-climbing capabilities. The robot features a four-wheel independent drive and steering system (4WID-4WIS), allowing it to maintain high maneuverab
Staircases are a challenging terrain frequently encountered in urban environments. While leg-wheel robots take advantage of having both legged and wheeled modes, their ability to negotiate stairs still requires careful planning. This paper presents a novel approach to developing a stair-climbing beh
The state estimation of legged robots often relies on ground contact detection. However, due to complex mechanisms and other factors, ground contact detection can be challenging to obtain in certain situations. This paper presents a velocity estimation method that combines inertia measurement unit (…
In this paper, we report the development of an innovative two-degrees-of-freedom (2-DOF) spherical parallel remote center of motion mechanism (SPRCMM), which can offer a wide range of movement in both DOFs without encountering singularities. To facilitate the design process, the paper briefly review
The leg-wheel transformable robot has the advantage of smooth, fast, and power-efficient motion on flat terrain and negotiability on rough terrain. This study presents a highly dynamic maneuver of the robot to leap onto a step using its legged form from its original form of wheeled driving, taking f…
We propose a limb trajectory planning method that considers both body and limb dynamics in robots, particularly suitable for those with non-trivial limb mass. To simplify the complexity and computation cost of using the full-body dynamics of the limbs, a reduced-order model that can simulate the dyn…
This article introduces an innovative model-based strategy for designing a legged robot to generate animal-like running dynamics with differentiated leg braking and thrusting force patterns. Linear springs were utilized as legs, but instead of having one end of each spring connected directly to the…
This research explored the generation of period-two dynamic running motion in a robot, based on the passive dynamic period-two motion of the reduced order, rolling spring-loaded inverted pendulum (R-SLIP) model. Each cycle of period-two motion consists of two stance phases separated by two flight ph…
We report on the development of a motion generation strategy that allows the robot to transit from one stable running motion to another in one stride by actively changing leg stiffness in real time. Stable motion of the robot is generated based on the stable fixed-point trajectories of the spring-lo…
We report on the model-based development of the pronking and trotting behaviors of a leg-wheel transformable robot. The spring-loaded inverted pendulum (SLIP) model serves as the motion template; its stable running motion is investigated, and the parameters and state conditions suitable for implemen
We report on the development of a robot's dynamic bounding locomotion based on a sagittal plane model that fits the robot's natural dynamics. The proposed model, referred to as the Two-rolling-leg (TRL) model, is a low degree-of-freedom planar rigid-body model with two rolling and compliant legs. Th
We report on the development of a dynamic gait in a robot based on a sagittal-plane and reduced-order model that fits the natural dynamics of the robot. The proposed model, referred to as the two-rolling-legs model with waist actuation (TRLW), consists of two rolling and compliant legs and two rigid…
We report on a model-based approach for robot design and its dynamic motion generation. A new torque-actuated dissipative spring loaded inverted pendulum model with rolling contact (TDR-SLIP) is proposed to serve as the motion template for the robot. It is a successor to a previously developed sprin…
We report on the model-based approach to dynamic trotting and pronking gait generation for a leg-wheel transformable robot. The rolling spring-loaded inverted pendulum (R-SLIP) model served as the template for robot locomotion by programming the robot's motion according to the stable fixed-point tra…