Joshua Brown

Particle jamming is an emergent technology widely used to create haptic devices that can change their physical stiffness to render hard or soft surfaces. Conventional implementations of particle jamming-based interfaces have relied on bulky and expensive vacuum systems to force the particles together. This paper presents designs for two alternative, mechatronic approaches to activating a particle jamming-based haptic interface. Each design is subjected to a battery of mechanical tests to evaluate the range and uniformity of the achievable hardness change and response time. Results are presented and the effectiveness of these designs is considered against established pneumatic approaches.

Whilst common in devices ranging from smart-phones to game controllers, vibrotactile feedback has generally been limited to providing a uniform sensation across a tactile surface. We propose a haptic interface based on the emerging physical effect of particle jamming with both vibrotactile and shape changing outputs, which can be extended in space to create haptic surfaces and devices with shape and vibrotactile responses localised to one part of the device. This paper gives an overview of the physical principles behind this technology and presents detailed performance metrics obtained from a working prototype. These include experimental characterization of the relationships between air pressure and electric motor power and vibration amplitude and frequency which show that it is possible to control vibrotactile amplitude and frequency independently.

Dealing safely with nuclear waste is an imperative for the nuclear industry. Increasingly, robots are being developed to carry out complex tasks such as perceiving, grasping, cutting, and manipulating waste. Radioactive material can be sorted, and either stored safely or disposed of appropriately, entirely through the actions of remotely controlled robots. Radiological characterisation is also critical during the decommissioning of nuclear facilities. It involves the detection and labelling of radiation levels, waste materials, and contaminants, as well as determining other related parameters (e.g., thermal and chemical), with the data visualised as 3D scene models. This paper overviews work by researchers at the QMUL Centre for Advanced Robotics (ARQ), a partner in the UK EPSRC National Centre for Nuclear Robotics (NCNR), a consortium working on the development of radiation-hardened robots fit to handle nuclear waste. Three areas of nuclear-related research are covered here: human–robot interfaces for remote operations, sensor delivery, and intelligent robotic manipulation.

Physical interaction with patients, for example conducted as part of a diagnostic examination or surgical procedure, provides clinicians with a wealth of information about their condition. Simulating this interaction is of great interest to researchers in both haptics and medical education, and the development of softness changing tactile interfaces is important in recreating the feel of different soft tissues. This paper presents designs for a variety of novel electromechanical and electromagnetic mechanisms for controlling particle jamming-based, hardness changing tactile displays, intended to allow medical trainees to experience these physical interactions in a range of simulation settings such as clinical skills teaching laboratories. Each design is then subjected to a battery of mechanical tests to evaluate its effectiveness compared to the state of the art, as well as their suitability for simulating the physical hardness of different types of soft tissues, previously characterised in established literature. These results demonstrate that all of the technologies presented are able to exhibit a measurable hardness change, with Shore hardness values between 3A and 57A achieved by the most effective constriction-based device. The electromechanical devices based on constriction and compression, and the state-of-the-art pneumatic device, were able to achieve hardness changes within a range that is useful for replicating the softness of organic tissue. The electromechanical and electromagnetic devices were also found to effect their full range of hardness change in less than a second, compared to several seconds for the state-of-the-art. These results show that the performance of softness changing tactile displays can be improved with the electromechanical actuation techniques proposed in this paper, and that such displays are able to replicate the physical characteristics of soft tissues and may therefore be of benefit in medical training and simulation scenarios.