Weight and volume changing device with liquid metal transfer

This paper presents a weight-changing device based on the transfer of mass. We chose liquid metal (Ga-In-Tin eutectic) and a bi-directional pump to control the mass that is injected into or removed from a target object. The liquid metal has a density of 6.44g/cm3, which is about six times heavier than water, and is thus suitable for effective mass transfer. We also combine the device with a dynamic volume-changing function to achieve programmable mass and volume at the same time. We explore three potential applications enabled by weight-changing devices: density simulation of different materials, miniature representation of planets with scaled size and mass, and motion control by changing gravity force. This technique opens up a new design space in human-computer interactions

ExTouch: Spatially-aware embodied manipulation of actuated objects mediated by augmented reality

As domestic robots and smart appliances become increasingly common, they require a simple, universal interface to control their motion. Such an interface must support a simple selection of a connected device, highlight its capabilities and allow for an intuitive manipulation. We propose "exTouch", an embodied spatially-aware approach to touch and control devices through an augmented reality mediated mobile interface. The "exTouch" system extends the users touchscreen interactions into the real world by enabling spatial control over the actuated object. When users touch a device shown in live video on the screen, they can change its position and orientation through multi-touch gestures or by physically moving the screen in relation to the controlled object. We demonstrate that the system can be used for applications such as an omnidirectional vehicle, a drone, and moving furniture for reconfigurable room

Sticky Actuator: Free-Form Planar Actuators for Animated Objects

We propose soft planar actuators enhanced by free-form fabrication that are suitable for making everyday objects move. The actuator consists of one or more inflatable pouches with an adhesive back. We have developed a machine for the fabrication of free-from pouches; squares, circles and ribbons are all possible. The deformation of the pouches can provide linear, rotational, and more complicated motion corresponding to the pouch's geometry. We also provide a both manual and programmable control system. In a user study, we organized a hands-on workshop of actuated origami for children. The results show that the combination of the actuator and classic materials can enhance rapid prototyping of animated objects.National Science Foundation (U.S.) (Grant 1240383)National Science Foundation (U.S.) (Grant 1138967

Pouch Motors: Printable Soft Actuators Integrated with Computational Design

We propose pouch motors, a new family of printable soft actuators integrated with computational design. The pouch motor consists of one or more inflatable gas-tight bladders made of sheet materials. This printable actuator is designed and fabricated in a planar fashion. It allows both easy prototyping and mass fabrication of affordable robotic systems. We provide theoretical models of the actuators compared with the experimental data. The measured maximum stroke and tension of the linear pouch motor are up to 28% and 100 N, respectively. The measured maximum range of motion and torque of the angular pouch motor are up to 80° and 0.2 N, respectively. We also develop an algorithm that automatically generates the patterns of the pouches and their fluidic channels. A custom-built fabrication machine streamlines the automated process from design to fabrication. We demonstrate a computer-generated life-sized hand that can hold a foam ball and perform gestures with 12 pouch motors, which can be fabricated in 15 min.National Science Foundation (U.S.) (1240383)National Science Foundation (U.S.) (1138967)United States. Department of Defens

Kinesthetic Sensing Exploiting the Active Interaction between the Environment and an Ostrich-Neck-inspired Manipulator

The 11th International Symposium on Adaptive Motion of Animals and Machines. Kobe University, Japan. 2023-06-06/09. Adaptive Motion of Animals and Machines Organizing Committee.Poster Session P1

Mowgli: a bipedal jumping and landing robot with an artificial muscoloskeletal system

Abstract — Jumping and landing movements are characterized by large instantaneous forces, short duration, and a high uncertainty concerning take off and landing points. Such characteristics make conventional types of control and robot design inadequate. Here we present an approach to realize motor control of jumping and landing which exploits the synergy between control and mechanical structure. Our experimental system is a pneumatically actuated bipedal robot called “Mowgli”. Mowgli’s artificial musculoskeletal system consists of six McKibben pneumatic muscle actuators including bi-articular muscle and two legs with hip, knee, and ankle joints. Mowgli can reach jump heights of more than 50% of its body height and can land softly. Our results show a proximo-distal sequence of joint extensions during jumping despite simultaneous motor activity. Extensions in the whole body motion are caused by the compliance and the natural dynamics of the legs. In addition to the experiments with the real robot, we also simulated two types of open loop controllers for vertical jumping with disturbance. We found that the model controlled by open loop motor command through a muscletendon mechanism could jump robustly. The simulation results demonstrate the contribution of the artificial musculoskeletal system as a physical feedback loop in explosive movements. I