In this paper, we investigate the limit cycle of a biped walker driven by pairs of pneumatic artificial muscles. We show, experimentally, that the period of the limit cycle changes when different control parameters are applied and estimate the relationship between the period and the parameters through trials. A step-by-step feedback controller is proposed to stabilize walking based on the estim...

Exploiting natural dynamics for bipedal locomotion, or passive walking, is gaining interest because of its energy efficiency. However, the natural trajectories of a passive walker are fixed during the design, thus limiting its mobility. A possible solution to this problem is creating a “semi-passive walker” equipped with actuators with adaptable compliance, which allows the natural dynamics to ...

By constructing Mckibben Muscles out of conductive fibers, we are able to measure the contraction and force output of the muscle without external encoders. These selfsensing actuators can then be controlled in flexible structures, without the rigid, well-defined joints demanded by typical position encoders. The contraction is manifest in changes in the inductance of the braid. The force output ...

This paper presents two control approaches for a linear axis with pneumatic muscles. Its guided carriage is driven by a nonlinear drive system consisting of two pulley tackles with pneumatic muscle actuators arranged at both sides. This innovative drive concept allows for an increased workspace as well as higher carriage velocities as compared to a direct actuation. Both proposed control scheme...

We want to describe the design of PULSE (Pneumatic Learning and Simulation Environment), an Intelligent Problem Solving Environment (IPSE) for pneumatic circuits based on a cognitive theory of knowledge acquisition (ISP-DLTheory). PULSE offers tasks given as a textual description and a time-discrete kind of a distance-time diagram. It supports unconstrained design of pneumatic circuits. PULSE o...

Three-dimensional tumor culture methods offer a high degree of biological and clinical relevance to in vitro models as well as cancer therapy. However, a straightforward, dynamic, and high-throughput method for micro-manipulation of 3D tumors is not yet well established. In this study, we present a novel and simple strategy for producing biomimetic 3D tumors in a controllable, high throughput m...

Robotic hands for dexterous manipulation and robust grasping have always been in high demand. Many applications of pneumatic devices are enabled due to recent developments in pneumatic actuation technology, for which previously only electric motors were suitable. Low stiffness and direct drive capabilities of pneumatic actuators enable smooth compliant geared electric motor systems. A new robot...

The common causes of rhabdomyolysis include trauma, hypoxia, drugs, toxins, infections and hyperthermia. Operative insults, including direct trauma and ischemia, have the potential to cause the development of rhabdomyolysis. Pneumatic tourniquets used during arthroscopic knee surgery to prevent blood loss have led to many complications such as nerve paralysis and vascular injuries. Rhabdomyolys...

Pneumatic drives are used in a wide range of industrial applications. Most of the pneumatic drive applications are simple point-to-point movements, where the motion characteristics is typically set up once by manual tuning. Changes in the operating conditions demand a new manual adjustment and thus additional costs. This work aims at developing a conrol strategy for pneumatic drives to save man...

The purpose of this study is to evaluate the efficacy of endoscopic fragmentation and removal of artificial calculi in a live porcine model employing intracorporeal pneumatic lithotripsy. In this experimental study, 7 submandibular ducts were accessed and artificial calculi placed. A salivary pneumatic lithotripter probe was inserted through an interventional sialendoscope to fragment the calcu...