Most land-air amphibious UAVs feature a four-wheel design that limits their adaptability in narrow and uneven spaces. This study proposes the rotor flywheel as a new land-air design that integrates a one-wheel structure and eight-rotor wings for more flexible motion. The dynamics model is then conducted with the Kane method, finding two power-saving self-balance state while rolling. Its controller design highlights the multi-input decoupling approach utilizing feedback, along with the dynamic model-based component to enable efficient control of its intricate operations. Results of simulations and experimental tests have validated the stability and adaptability of the mode-switching and rolling of the robot in ground motion.

In this paper, we propose the reduced model for the full dynamics of a bicycle and analyze its nonlinear behavior under a proportional control law for steering. Based on the Gibbs-Appell equations for the Whipple bicycle, we obtain a second-order nonlinear ordinary differential equation (ODE) that governs the bicycle’s controlled motion. Two types of equilibrium points for the governing equation are found, which correspond to the bicycle’s uniform straight forward and circular motions, respectively. By applying the Hurwitz criterion to the linearized equation, we find that the steer coefficient must be negative, consistent with the human’s intuition of turning toward a fall. Under this condition, a critical angular velocity of the rear wheel exists, above which the uniform straight forward motion is stable, and slightly below which a pair of symmetrical stable uniform circular motions will occur. These theoretical findings are verified by both numerical simulations and experiments performed on a powered autonomous bicycle.

Inspired by geckos, we built a new configuration for climbing robot, the GPL model with one passive waist and four active axil legs. In this paper, further research was made to analysis its motion. We found the anomalies line between supporting feet and its effect on robot motion. A step further, the principia of configuration design and gait planning were proposed based on dynamic analysis. The prototype was developed and the climbing forces experiment was carried out. We testified the rationality of GPL model and waist trajectory planning. Also, energy analysis was proven by the driving forces measured on the supporting feet. In our experiment, the deceleration force during the robot climbing was only provided by the gravity, indicating a potential space for speed improvement without significant energy waste.

The redundant driving problem is an inherent phenomenon existing in a modular caterpillar robot. To limit the internal forces arising from the redundant driving, this paper proposes a joint torque control method, which is based on an assumption that there is only one active joint in the four-link mechanism driving the climbing gait. Except the active joint, the other three joints are all considered as passive joints, whose torques tend to be zero, although they are driven by motors in reality. According to the analyses of static forces in the closed chain state, the ideal torque of named active joint is calculated, and will be followed by the joint in real climbing locomotion. The experiments reveal the reasonability and feasibility of the proposed joint control method, as well as the limitations of current prototype and control algorithm.

This paper presents an efficient kinematical solution to a multi-robot system with serial and parallel mechanisms. JL-I is a reconfigurable robot featuring active spherical joints formed by serial and parallel mechanisms endowing the robotic system with the ability of changing shapes in three dimensions. The active joint here can combine the advantages of the high rigidity of a parallel mechanism and the extended workspace of a serial mechanism. However, the kinematic analysis of the serial and parallel mechanism is always the bottleneck in designing a robot and control realization. In order to deal with this problem, the whole kinematical analysis is organized in the sequence from the direct mechanical analysis related to the serial and parallel mechanism over the numerical solutions to the simplified kinematics expression. The latest results obtained demonstrate that the deduced closure-form solution is time efficient and easy to implement while offering a satisfactory motion performance in on-site experiments.

JL-2, as a new version of the JL reconfigurable mobile robot system, features not only a docking and 3D posture adjusting capability between its robots, but also a multi-functional docking gripper. The basic concept of JL is that the robots in the system can simultaneously perform basic tasks in flat terrains, and in the case of rugged terrains, the robots can interconnect to enhance their locomotion capabilities. This paper introduces new designs for JL-2 by which the docking mechanism can be used as a simple gripper with 3 DOFs. Then the technologies of the docking mechanism are discussed in detail, including the workspace of the docking gripper, the docking procedure and analyses of the self-aligning ability. Then the workspaces of the posture adjusting mechanisms between two docked robots are analyzed to clarify the reconfiguration ability of JL-2. At last, a series of real experiments are proposed to test the designs and analyses and the basic performance of JL-2.

Based on the modular concept, this paper presents two caterpillar robot prototypes which are inspired by two typical caterpillars: Inchworm and Pine Caterpillar. The inchworm robot prototype features simplest kinematics and open chain architecture. Due to the fact that there is only one attachment module supporting the inchworm robot during crawling, we apply an Unsymmetrical Phase Method (UPM) to realize a stable crawling gait for it. A pine caterpillar robot is derived from combining two inchworm robots together. The crawling gait of it features a repetitive changing chain: Open-Closed-Open. Besides the UPM in open chain states, a four-links kinematic model is applied to control the corresponding joints to transfer the crawling wave along the robot body in the closed chain state. These two prototypes are all constructed and, and their crawling locomotion abilities have been tested on vertical glasses respectively.

To overcome the overshoot and oscillation in the normal Bang-Bang controller applied in the pneumatic driving glass-wall cleaning robot, this paper presents a F&A compensating variable Bang-Bang control algorithm for the pneumatic position servo. Besides a new cylinder driving plan is designed, the control algorithm is also improved by adding a fiction force compensating item in the chamber force evaluation equation. To adjust the controlling parameters dynamically, certain increasing functions, such as step function, linear function and arc-tangent function, are used to define the piston's expectative acceleration along with the reduction of the piston's position error. To testify the feasibility of the control algorithms with the above three expectative acceleration setting functions respectively, a pneumatic glass-wall cleaning robot "Sky Cleaner 4" is used as a testing platform to implement a series of on-load position servo experiments. And the different results of them are compared.

Reconfigurable robots consist of many modules which are able to change the way they are connected. As a result, the robots have the capability of adopting different configurations to match various tasks and suit complex environments. This paper presents a novel field robot named JL-I which consists of three uniform modules. With the docking mechanisms, the modules can connect or disconnect flexibly and automatically. Furthermore the active joints formed by serial and parallel mechanisms endow the robot with the ability of changing shape in three dimensions. Consequently useful locomotion capabilities, such as crossing high vertical obstacles, getting self-recovery when the robot is upside-down are achieved. After describing the structural principle of the robot, the related kinematics analysis follows. In the end, the successful on-site tests confirm the principles described above and the robot's ability.