Advances in legged robotics have led to the development of robots capable of running over rough terrain. Edubot, one such hexapedal robot, is a biologically inspired runner that mimics the cockroach in its alternating tripod gait and compliant legs. Most animals’ running gaits can be approximated by the Spring-Loaded Inverted Pendulum (SLIP) model, which treats an animal as a point mass on a li...

Design of haptic systems that guarantee stable interaction is a challenging task. Virtual environments are typically highly nonlinear—resulting in a nonpassive discrete-time model. This paper will investigate how nonlinear mass/spring/damper virtual environments can be designed to guarantee the absence of oscillations and other chaotic behavior in the signal presented to the human operator. In ...

Spring-like leg behavior was found in the global dynamics of human and animal running in sagittal plane. The corresponding template model, the conservative spring-loaded inverted pendulum (SLIP), shows stability for a large range of speeds and is, therefore, a promising concept for the design of legged robots. However, an anchoring of this template is needed in order to provide functions of bio...

Series Elastic Actuators have linear springs intentionally placed in series between the motor and actuator output. The spring strain is measured to get an accurate estimate of force. Despite using a transmission to achieve high force/mass and high power/mass, the spring allows for good force control, high force fidelity, minimum impedance, and large dynamic range. A second order linear actuator...

This paper presents a new method for real-time modelling soft tissue deformation. It improves the traditional mass-spring model with conical springs to deal with nonlinear mechanical behaviours of soft tissues. A conical spring model is developed to predict soft tissue deformation with reference to deformation patterns. The model parameters are formulated according to tissue deformation pattern...

It has previously been shown that a bipedal model consisting of a point mass supported by spring limbs can be tuned to simulate periodic human walking. In this study, we incorporated roller feet into the spring-mass model and evaluated the effect of roller radius, impact angle, and limb stiffness on spatiotemporal gait characteristics, ground reactions, and center-of-pressure excursions. We als...

In our investigation, we used Hamiltonian dynamics to model two different spring-pendulum systems in MATLAB. First, we confirmed that chaotic motion is possible in the classic single spring-pendulum system in two dimensions and without damping. Next, we modified the system by attaching the mass to two springs (Figure 1b) and tested to see how the dynamics change with the addition of this second...

In this paper, a procedural method for the visualization of knitted and woven fabrics is presented. The proposed method is compatible with a mass-spring model and makes use of the regular warp–weft structure of the cloth. The visualization parameters for the loops and threads are easily mapped to the animated mass-spring model. The simulation idea underlying both knitted and woven fabrics is si...