Catalogue

Explorer

Reaching the unreachable

To best view the table please contact explorer@ocrobotics.com and we will send you the catalogue. The catalogue is also available as a download.

The main table in the catalogue (illustrated below) identifies the different snake-arms in the Explorer range. The Explorer snake-arm diameters vary from 40mm to 150mm. Payloads are provided for each diameter arm for different length arms. The table also identifies the different options available with each snake-arm size.

The Explorer range of snake-arm robots is designed to enable you to conduct automated operations within confined spaces. The snake-arms defined in this catalogue are general purpose tools which occupy the mid-range for diameter, reach, payload, curvature and precision. Confined spaces are all different; please contact us to discuss your snake-arm robot application.

Snake-arm robot basics

One principle and four components:

The nose-following principle - The best way to reach inside a confined space is to snake inside, with the body of the device following where the tip has gone. We achieve this by coordinated motion of the whole arm. When the tip reaches an open space, it can be moved in all directions.

User Interface - The user interface generally consists of a laptop or PC running the snake-arm application, and a multi-function joystick. Fixed installations may include additional controls for cameras, lights and tools. Our control software is developed in house, which means we can adapt our software to your requirements.

Actuator Pack - The shape and stiffness of a particular snake-arm is controlled by wire ropes that transfer mechanical power from the actuator pack into the snake-arm. This arrangement keeps the motors and power electronics accessible and outside the confined or hazardous space.

Snake-arm - A snake-arm is made up of articulating links. Both the number and length of the links can be varied giving a wide choice of final performance. Different snake-arms can be interchanged on the same actuator pack. All snake-arms are hollow and are designed to have minimum mass for maximum reach, whilst not compromising rigidity and stiffness.

Tool - Fixed or interchangeable tools and sensors are located at the tip of the snake-arm, although sensors may be distributed along its length. Services are routed through the hollow central bore.

Options

Introduction Orientation - Actuator pack orientation and gravity have a substantial effect on payload capacity. The arm payloads given in the table are guidelines based on the orientation shown (H/V). Horizontal Reach (HR) is generally much more significant than Vertical Reach (VR). Please talk to us about your specific application for more guidance.

Payload - A high payload version is available for all snake-arm options. This is achieved by choosing higher specification materials and components. Payload, speed and curvature are all interrelated, allowing for task specific optimisation.

Speed - For confined spaces we have found that overall process time is more important than snake-arm top speed. Our snake-arms are generally built to maximise payload with a typical tip speed of 1m/s. Reducing the dynamic response of the snake-arm (increasing settling time) allows an increase in payload and/or speed.

Precision Metrics - Snake-arm motion is inherently well damped. Motion Resolution (MR) is the smallest increment of controlled motion - typically 0.01mm. Repeatability is the ability to return to the same configuration - typically 0.1mm. Accuracy is a process-related issue dependent on many factors.

Introduction Axis - The Rail&Rotate™ may be replaced by a telescopic introduction axis to increase reach. Snake-arms can also be mounted on an industrial robot. A mobile vehicle mounted solution is available.

Arm Extensions - All the snake-arms can be provided with extensions between the arm and the actuator pack. This can be used to further distance the motors from a hazardous environment or to increase reach.

Quick Release - Enabling snake-arms to be exchanged allows a wider range of capability and performance. Reasons for changing a snake-arm may include: changing function (payload, length, tool); rapid recovery; disposability; sterility; and, planned refurbishment.

Curvature - Higher curvature snake-arms are possible. Increasing curvature of the arm requires increased rope stroke and a longer actuator pack. Payload generally decreases with increased total curvature.

Protective Skins - Our skins provide a simple sterile barrier between your product and process and the snake-arm for the benefit of both. Skins can be provided for the external and internal surfaces and can be made user-changeable.

Hazardous Environments - OC Robotics snake-arm robots are well suited to hazardous environments. Moving motors and electronics out of the arm means that arm materials may be chosen to allow for radiation, heat, vacuum, magnetic fields, and operations in explosive atmospheres or a range of fluids including air and water.

Tools and processes - Robots are 'only the delivery mechanisms'. Designing tools and sensors for confined spaces often involves miniaturising existing designs and sometimes requires a complete rethink. We have a team dedicated to tool design and process development. Standard tools include video cameras and lighting packages. We have delivered solutions for welding, grasping and cutting and have mock-up facilities for development activities.

Software - SoftSnake™ is a simulation environment based on our hardware GUI that allows control of different snake-arms within a virtual model. The basic package includes one snake-arm from each of the featured sizes and some generic environments. We also offer consultancy to add new environments and confirm snake-arm suitability.

Other ranges - Our battery or mains powered portable 12.5mm diameter snake-arm is our smallest to date. With an unsupported length of 600mm it is also our most slender. For longer reach applications we can build neutrally buoyant snake-arms for underwater applications and, along similar lines, the PipeSnake™ range of products take advantage of wall support to reach further into structures and around multiple bends.

Philosophy - Snake-arm robots are designed to extend the reach of the human hand. They were born out of a question: "What is a suitable robot for operating in the human brain?" We soon recognised the similarities between brains and bombs, and then nuclear reactors and aircraft engines. Getting out is often more important than getting in. This realisation has driven all our design effort. Providing a simple, light, slender snake-arm with constant diameter minimises snagging risks. Inherent redundancy within the design underpins safe and reliable operation.

A snake-arm robot is a tool for our times; financial and environmental considerations are key drivers in the maintenance and life extension of assets. The capital invested in plant and equipment is huge and the cost of replacement is greater. Maximising up-time whilst reducing risk is critical for asset management and profitable life extension. By choosing different words, this maxim works equally well for nuclear reactors, oil platforms, bomb disposal and human surgery. Many situations will benefit from a minimally invasive approach. Our robots can also enable product (r)evolution by enabling new assembly and inspection philosophies.

Intuitive operation - We have designed robots for 24-7 operation working from pre-programmed motion sequences for repetitive tasks. Alternatively, many tasks require so called 'man-in-the-loop' real time control to navigate within unknown or variable spaces. For both types of application, our nose-following software allows the operator to fly-the-tip, in path-following or standard Cartesian modes with the computer taking care of the rest. RetractOne™ is provided as standard and allows the operator to back up safely with one thumb speed control. StopOnContact is coming as part of the SnakeSkin option pack, and more advanced capabilities, including automated search, will be possible in future.