The Infona portal uses cookies, i.e. strings of text saved by a browser on the user's device. The portal can access those files and use them to remember the user's data, such as their chosen settings (screen view, interface language, etc.), or their login data. By using the Infona portal the user accepts automatic saving and using this information for portal operation purposes. More information on the subject can be found in the Privacy Policy and Terms of Service. By closing this window the user confirms that they have read the information on cookie usage, and they accept the privacy policy and the way cookies are used by the portal. You can change the cookie settings in your browser.
A Force Threshold-based Position (FTP) controller is presented for cyclic legged locomotion over irregular terrain. Force feedback in the form of threshold comparison is used to control each leg independently. The FTP controller decouples the control of individual legs and uses only localized feedback to generate joint torques. No feedback of body state is needed and no multi-leg Jacobian is computed...
A novel behavior based locomotion controller (BBLC) capable of adapting to unknown disturbances is presented. The proposed controller implements a behavior based control architecture by subdividing the walking control into several task-space controllers such as swing leg control and center of gravity (COG) position control. For each task-space controller, a number of behaviors, which plan the reference...
This paper proposes the novel force control method based on higher-order derivative for high-backdrivable actuation of the robot employing elastomer-based series elastic actuators (SEAs). Control of SEAs is generally difficult because they consist of an underactuated 2-inertia system. Previously, we control it with a position control method. Lately, we employ a torque control method to overcome several...
Biological studies on animal walking and running have contributed to the control of mobile robots. Taking inspiration from such studies, a hybrid impulse-position (HIP) controller has been developed for legged locomotion over uneven terrain. The HIP controller generates joint torques during the stance phase of each leg cycle to propel and stabilize the body, and is meant to operate with CPG-based...
In this paper, we present a new concept of multi-legged seabed robot for high tidal current environment. The robot moves on seabed by walking with 4 or 6 legs which is different moving mechanism from the existing underwater thrust system such as screw or Caterpillar. The main concept to endure the high current is utilization of hydrodynamic forces acting on the body and legs. The advantage of this...
This paper deals with the locomotion control of quadruped robots inspired by the biological concept of central pattern generator (CPG). A control architecture is proposed with a 3-D workspace trajectory generator and a motion engine. The workspace trajectory generator generates adaptive workspace trajectories based on CPGs, and the motion engine realizes joint motion imputes. The proposed architecture...
Usually the bipedal robots use knee joints with only one degree of freedom. Several biomechanical researches have proved that the human knee joint is a complex joint with more than one degree of freedom. In the sagittal plane the human knee joint allows a rolling and a sliding of the thigh on the shin. In the case of a bipedal robot we propose a closed structure, called cross four-bar knee, which...
This article is aimed at presenting a technique to generate bipedal walking trajectories that can be applied to humanoid robots. The proposed method is based on maintatining the dynamic balance by using the ZMP criterion throughout single support phases. To be able to reach this goal, we employed ZMP equations in spherical coordinates, so that the rate change of intrinsic angular momentum terms in...
This paper presents a new controller that can achieve an asymptotically stable, periodic walking gait for a 3D biped robot, which has 14 DOF in the single support phase and 14 actuators. In order to avoid the unexpected rotation of the supporting foot, two positions of the zero moment point or ZMP in the horizontal plane are regulated. For a 3D robot with 14 actuated joints, since the 2 positions...
This paper proposes a strategy for bipedal robot walking on inclined surfaces using position and orientation based inverse kinematics algorithm. Some researchers implemented control approaches to solve bipedal walking on inclined surfaces. Generally, most of them apply control feedback at ankle joints and also introduced many more control methodologies. In this paper, inverse kinematics methodology...
There are types of walking robots using wheels with their legs. Among those, the robots with passive wheels generate propulsive force by specially designed periodic leg motions. The authors had proposed to use a special axle mechanism that can change its curvature to track a designed path for propulsion. The mechanism showed not only straightforward motion but also curved motion and pivoting motion...
Considering the difficulty in regeneration the stroke patient's neurons by modern medicine, the rehabilitation robots are widely studied to help the patient reduce influence caused by the stroke illness. In this paper, the lower limb rehabilitation robot, which has eight degree of freedoms, is studied. The motion data of the lower limb rehabilitation robot are got by the great number of models provided...
To solve the problem that the final velocity curve will be unsmoothed if the PVT(Position Velocity Time) nodes velocities are determined improperly when using PVT control algorithm, based on analyzing the general principle of spline interpolation and PVT motion control, this paper presents a triple spline interpolation based PVT algorithm, which ensures the smoothness of the velocity curve. The velocity...
Most humanoid robots walk with bent knees, which particularly requires high motor torques at knees and gives an unnatural walking manner. It is therefore essential to design a control method that produces a motion which is more energy efficient and natural comparable to those performed by humans. In this paper, we address this issue by modeling the virtual spring-damper based on the cart-table model...
This paper discusses biped walking which is robust to external disturbances and how it could be realized by means of achieving compliance and dynamic trajectory generation. A method of limiting the ground reaction forces is presented. It is mathematically equivalent to a conventional position control system when the ground reaction forces are within the set limits, therefore in this case the positioning...
The ability of walking in a wide variety of terrains is one of the most important features of hexapod insects. In this paper we describe a bio-inspired controller able to generate locomotion and switch between different type of gaits for an hexapod robot. Motor patterns are generated by coupled Central Pattern Generators formulated as nonlinear oscillators. These patterns are modulated by a drive...
A mobile robot based on novel line-walking mechanism is proposed for inspecting power transmission lines. The novel mechanism enables the centroid of the robot to concentrate on the hip joint to minimize the drive torque of the hip joint and keep the robot stable when only on leg is hung on line. After reviewing of the line-walking mechanism, power line inspection robot is described in detail. The...
In this paper, a distributed motion control system is designed and achieved for the modular quadruped robot based on CANopen network. A communication network is built among modules and joints through CANopen network. Controllers and encoders are used to achieve closed-loop control belonging to speed and position for each joint and complete real-time multi-jointed linkage. Moreover, experimental results...
In this paper, stable hopping of a one-legged, articulated robot with a flat foot is investigated. The robot has a special feature that before taking off, it goes through an underactuated phase in which the foot rotates about the unactuated toe on the ground. By having the underactuated phase, the robot can perform stable human-like hops with longer hopping distances. To devise a systematic trajectory...
This paper proposes a novel user interface for creating whole body motions of biped humanoid robots just by giving key poses. Although such an interface is popular for CG character animation, there have not been any practical systems that can appropriately handle the kinematic and dynamic conditions required for moving actual biped robots stably without falling down. In our interface, every time a...
Set the date range to filter the displayed results. You can set a starting date, ending date or both. You can enter the dates manually or choose them from the calendar.