Editor's Choice


The nanoclutch

1st Quarter 2016 Editor's Choice Shaft power components

A model microscopic system to demonstrate the transmission of torque in the presence of thermal fluctuations – necessary for the creation of a tiny clutch operating at the nanoscale – has been assembled at the University of Bristol as part of an international collaboration.

When driving a car, the clutch mechanically carries the torque produced by the engine to the chassis of the vehicle – a coupling that has long been tested and optimised in such macroscopic machines, giving us highly efficient engines. For microscopic machines, however, developing a clutch which can operate at the nanoscale is much more challenging because at this level different physics need to be considered. Thermal fluctuations play an increasingly dominant role as a device is miniaturised, leading to increased dissipation of energy and the need to develop new design principles.

Principle of operation of the nanoclutch: red spheres rotate clockwise and an opposing torque is applied to a central axle.
Principle of operation of the nanoclutch: red spheres rotate clockwise and an opposing torque is applied to a central axle.

In the model microscopic system developed by scientists from Bristol, Düsseldorf, Mainz, Princeton and Santa Barbara, a ring of colloidal particles is localised in optical tweezers and automatically translated on a circular path, transferring a rotational motion to an assembly of identical colloids confined to the interior region.

Dr Paddy Royall of the University of Bristol said: “This device looks a lot like a washing machine, but the dimensions are tiny. Through optical manipulation the particle ring can be squeezed at will, altering the coupling between the driven and loaded parts of the assembly and providing a clutch-like operation mode.”

Colloidal suspensions fall into the category of materials known as soft matter and the softness of the rotational device is shown to lead to new transmission phenomena not observed in macroscopic machines. “Exploiting the softness of nanomaterials gives us additional and unprecedented control mechanisms which may be employed when designing microscopic machines,” Dr Royall explained.

In addition to the experiments performed at the University of Bristol, physicists at the University of Düsseldorf have developed model computer simulations to further investigate torque coupling at the nanoscale. This enables the measurement of nanomachine efficiency, which is small but can be optimised through careful control of the system parameters.

The researchers have identified three different transmission regimes: a solid-like scenario which transmits torque much like a macroscopic gear; a liquid-like scenario in which much of the energy input is lost to friction and an intermediate slipping scenario unique to soft materials, which combines aspects of the solid-like and liquid-like behaviours.

“A basic understanding of the coupling process will give us insight into the construction of nanomachines, in which torque transfer is absolutely essential,” said Professor Hartmut Loewen of the University of Düsseldorf.

For more information contact Paddy Royall, University of Bristol, +44 117 928 7668, [email protected]





Share this article:
Share via emailShare via LinkedInPrint this page

Further reading:

Planar motor system for quality assurance
Beckhoff Automation Editor's Choice Electrical switching & drive systems & components
Achieving the shortest possible inspection times, even when working with different components, is paramount when it comes to series production. This is precisely what special machine builder, stoba Sondermaschinen set out to achieve with its InspectorONE optical inspection system, which is based on deep learning and features the Beckhoff XPlanar planar motor system at the conveyor system core.

Read more...
Robotic solution for adhesive tape application with flexible control
Beckhoff Automation Editor's Choice Robotics & Mechatronics
In industry, even elaborate processes, such as the application of adhesive tape to parts with varying geometries are automated. Innovative Automation has developed a platform with Beckhoff control technology and a remote feeding module, which increases productivity and enables flexible customisation for different requirements.

Read more...
The world’s most powerful worm
Editor's Choice Electrical switching & drive systems & components
Geothermal energy from the natural heat of the Earth is an inexhaustible resource, yet the growth of the global geothermal power sector lags behind other renewable energies. Now Swiss startup, Borobotics is hoping to speed this up with its innovative new electric-powered geothermal drilling robot, which can be used to fast-track and lower the cost of heat pump installations in confined spaces.

Read more...
Problem solving under pressure
Axiom Hydraulics Editor's Choice
The greatest strength of Axiom Hydraulics lies in the company’s ability to solve complex problems and adapt systems to meet unique challenges. This capability stems from two key factors: the diverse experience of its team members, which spans decades across multiple disciplines, and their unwavering dedication to their clients.

Read more...
New AI advisor for robot selection
igus Editor's Choice Robotics & Mechatronics
igus’ new AI chatbot has been added to the online platform RBTX.com. The interactive consultant is designed to enable companies with little previous experience and technological expertise to quickly and reliably put together low-cost automation solutions to becoming more competitive.

Read more...
Compressed air treatment do’s and don’ts
Artic Driers International Editor's Choice Pneumatic systems & components
As a long-established importer and manufacturer of air dryers, Artic Dryers often sees the results of poor installation and issues with aftercoolers that create serious problems in air drying systems.

Read more...
Process control system for the entire plant lifecycle
Siemens South Africa Editor's Choice
The automation of process plants has been characterised by IT silos for a long time. The high level of IT security required was achieved through strict isolation from the outside world. However, this made unlocking the opportunities for digitalisation very difficult. This is a compelling reason to opt for Simatic PCS neo – Siemens’s completely web-based process control system with state-of-the-art IT security concepts.

Read more...
Celebrating 65 years: rebuilding and redefining its legacy
Axiom Hydraulics Editor's Choice News & events
Founded in 1959 by Neill Simpson, Axiom Hydraulics has grown into one of South Africa’s elite hydraulic companies. Over the past six and a half decades they’ve weathered many challenges, but none as devastating as the fire of 2023.

Read more...
Monitoring the health of systems
SA Gauge Editor's Choice Shaft power components
Pressure and temperature gauges are vital instruments in various industries. However, they are susceptible to failures that can compromise their accuracy and reliability. When these gauges fail, the consequences can be severe.

Read more...
PC-based control for advanced hydrogen storage technology
Beckhoff Automation Editor's Choice Electrical switching & drive systems & components
The proportion of renewable energies from solar, wind and water is rising continuously. However, sufficient storage options are of the essence to use these energies as efficiently as possible. GKN Hydrogen offers a particularly compact and safe option, low-pressure metal hydride hydrogen storage systems with PC-based control from Beckhoff.

Read more...