Shape-locking in architected materials through 3D printed magnetically activated joints

Shape morphing is the ability of objects to adapt to different shapes and reduce stress concentrations through increased contact area. This is a common trait of natural and engineered objects and has several applications in, among others, soft robotics and orthopedic implants. Shape morphing is achieved through flexible materials or rigid...

A single input contact-based compliant switching mechanism

In the field of mechanical metamaterials, unconventional physical properties are realized by changing the geometric structure of a unit cell. A metamaterial is composed of numerous unit cells. Researchers have taken it a step further by making a reprogrammable unit cell. A reprogrammable metamaterial has additional elements or mechanisms in the...

Large-scale transportation and storage of wood pellets: Investigation of the change in physical properties

The change in physical properties of wood pellets, with a focus on particle size distributions due to pellet breakage and attrition, was studied in a large-scale (∼450 ton/h) transportation system. Critical locations with a high probability of breakage through the whole transportation system were chosen and sampled to study the effect of...

Higher-order derivatives of rigid body dynamics with application to the dynamic balance of spatial linkages

Dynamic balance eliminates the fluctuating reaction forces and moments induced by high-speed robots that would otherwise cause undesired base vibrations, noise and accuracy loss. Many balancing procedures, such as the addition of counter-rotating inertia wheels, increase the complexity and motor torques. There exist, however, a small set of...

The Effect of Environmental Conditions on the Degradation Behavior of Biomass Pellets

Biomass pellets provide a pivotal opportunity in promising energy transition scenarios as a renewable source of energy. A large share of the current utilization of pellets is facilitated by intensive global trade operations. Considering the long distance between the production site and the end-user locations, pellets may face fluctuating storage...

The Effect of Biomass Pellet Length, Test Conditions and Torrefaction on Mechanical Durability Characteristics According to ISO Standard 17831-1

With the recent increase in biomass pellet consumption, the mechanical degradation of pellets during transport and handling has become more important. ISO standard 17831-1 is an accepted global standard that is commonly used amongst researchers and industries to determine the mechanical durability of pellets. However, the measured mechanical...

Cellular processes under mechanical stress: Designing an in vitro model for testing burn splinting strategies

Introduction. To prevent burns from scar formation and contraction, the use of splinting therapy in the early phase of wound healing is considered as an effective non-surgical method. Splinting entails the application of a mechanical load in the opposite direction of the contractile force within the wound, based on the assumption that wound- or...

The Effect of Pellet Length on Mechanical Durability and Breakage Behaviour of Torrefied Biomass

The transportation, handling, and storage of biomass pellets are challenging due to pellet breakage and fines generation. The amount of fines generated during transportation and handling of biomass pellets is mostly measured in the laboratory using mechanical durability testers such as tumbling can method according to ISO 17831-1. This standard...

A screw based methodology for instantaneous dynamic balance

Fast-moving industrial robots exert large varying reaction forces and moments on their base frame, inducing vibrations, wear and accuracy degeneration. These shaking forces and moments can be eliminated by a specific design of the mass distribution of the robot links, resulting in a dynamically balanced mechanism. Obtaining the conditions for...

Multiscale Modeling of the effect of sub-ply voids on the failure of composites: A progressive failure model

The effective fracture behavior of a fiber-reinforced composite depends on both the design and manufacturing of the material. During manufacturing several type of defects can occur. One of these defects are micro-voids on the sub-ply level. These can consist of either matrix voids or gaps between the fibers due to the inability of the resin to...