Choosing the Right Robot

Robotics has been advancing at a rate of knots over the past 10 years and although the time of replacing the majority of manual labour with robot operations is still a long way off, there are some interesting new industrial robots appearing which come much closer to undertaking human tasks.  As an experienced robot integrator with years of experience and hundreds of installations, Cyan Tec Systems is well-placed to offer advice on the best and latest robot automation solutions.

Many suppliers are offering the new style of “collaborative robots”, one example of which is the YuMi robot from ABB, which has been launched recently.  This is perhaps the most mainstream of this genre, coming from one of the “big four” global robot suppliers which are expected to grow rapidly to take the place of more expensive robots or human operators.

What does the YuMi do?

The YuMi robot looks a lot more like, and shares many characteristics with, the human body.  Designed to work alongside humans, the most notable change from the typical industrial 6-axis robot is the fact that YuMi is designed to work in the open and not behind guarding and safety interlocks.

Image: YuMi robot (image courtesy of ABB Robotics)

YuMi is equipped with twin articulated arms which terminate in gripper hands.  The concept of collaborative robots is that a shop floor may consist of a mixture of humans and robots, the robots being able to feed or be fed by human operators who might be given the more complicated tasks (or tasks requiring human intelligence).  Movement speed is restricted and the arms are equipped with crash sensors to stop safely if they should come into contact with a human operator, avoiding the risk of pinch, crush or impact injuries.

Ideal for small electronic component assembly, the robot will not replace the traditional 6-axis industrial robot, rather it complements the range and expands the capabilities of robot-based automation.  The YuMi robot can use vision to correctly pick and place components regardless of orientation and with the ability to compensate for inaccuracy of position, in the same way a human would.  As well as having the dexterity of a human operator, the collaborative robot can be easily trained and re-trained, coping well with boring, repetitive or ergonomically challenging tasks.

Traditional robots

For some applications, where long reach or interpolated path following is required, there is no substitute for the speed and accuracy of the traditional 6-axis robot.  These robots are still the obvious choice where the robot is using a tool which necessitates full safety guarding (for example laser welding or cutting).  In these applications, the capability of the 6-axis robot makes it the most appropriate choice.

In other applications involving simpler action, it might be that a Scara robot with 4-axes is more suitable.  These robots have fewer movements than the full 6-axis robot and are often used for pick-and-place in assembly or in loading and unloading machines.

Conclusions

With robots, as with other elements in automation, there is no single solution which suits every situation.  Flexibility and open-mindedness will allow the optimum configuration to be found, taking into account all the criteria required by the application.  In the next decade it is likely that many more collaborative robots will be installed and new technology is enhancing the vision, motion accuracy and intelligence of robots.

When to use a SCARA Robot

What is a SCARA robot?

SCARA robots were first developed in the 1980’s in Japan and the name SCARA stands for Selective Compliance Assembly Robot Arm.  The main feature of the SCARA robot is that it has a jointed 2-link arm which in some ways imitates the human arm although it operates on a single plane, allowing the arm to extend and retract (fold) into confined areas which makes it suitable for reaching inside enclosures or pick-and-place from one location to another.  The SCARA robot is one of 3 major classes of robot which Cyan Tec Systems are experienced at integrating, namely:

  • Cartesian Robots (Gantry type)
  • Six-axis Robots
  • SCARA Robots

The selection of which type of robot to choose is not always clear-cut, but Cyan Tec Systems are in a totally unbiased position to recommend the best solution for the particular automation requirement.  This article considers the specific case of the SCARA robot and when it is most likely advantageous to use one.  In some cases the selection of the most suitable robot is straightforward and in others it is mainly down to a comparison on cost.   SCARA robots normally have up to 4 axes (3 rotation and one Z linear).

Selective Compliance Assembly Robot Arm – CYAN TEC

 

Advantages of SCARA robots

The SCARA robot is most commonly used for pick-and-place or assembly operations where high speed and high accuracy is required.  Generally a SCARA robot can operate at higher speed and with optional cleanroom specification.  In terms of repeatability, currently available SCARA robots can achieve tolerances lower than 10 microns, compared to 20 microns for a six-axis robot. By design, the SCARA robot suits applications with a smaller field of operation and where floor space is limited, the compact layout also making them more easily re-allocated in temporary or remote applications.

 

Limitations of SCARA robots

SCARA robots, due to their configuration are typically only capable of carrying a relatively light payload, typically up to 2 kg nominal (10 kg maximum).  The envelope of a SCARA robot is typically circular, which doesn’t suit all applications, and the robot has limited dexterity and flexibility compared to the full 3D capability of other types of robot.  For example, following a 3D contour is something that will be more likely fall within the capabilities of a six-axis robot.

 

Choosing the right solution

With many different factors influencing the choice of the robot for a specific application, it is wise to discuss with an automation expert.  Cyan Tec Systems have been integrating all types of robots for several decades and can advise on alternative concepts for system design and help to select the most suitable configuration.   Working with an experienced and independent supplier is the best way to define the automation configuration that suits the cycle time, accuracy and budget of the required production system.

Cyan Tec Systems has experience of integrating robots for assembly and loading/unloading of machinery.  Cyan Tec also offers systems for paint spraying, assembly, test and laser processing applications. Standard and bespoke systems are offered with a full service from design through manufacture, a large installed base worldwide is supported by a dedicated team of engineers.

Laser Cutting: Product Focus

Laser cutting of a variety of different materials, particularly metals and fabrics, is fairly common nowadays. Therefore, when an automotive supplier contacted Cyan Tec Systems Limited to design and manufacture an automated piece of equipment to remove excess material from their complex 3D formed products, the perfect solution was developed and in turn the RRTS14CC standard laser cutting cell was established.

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Cyan-Tec: Laser Cutting

One of our laser source suppliers describe laser cutting as “a process where a material is cut, and this can be for small & fine materials or materials with a much greater level of thickness”.

They continue by stating “Laser cutting has a number of application areas, particularly in industrial manufacturing where a higher output is required but is also used in schools, Aerospace the military and in small businesses”.

The integration of a rotary transfer system, a six axis robot and fixed laser optics ensured that the customer is not only satisfied with the much-improved cycle time that the cell can offer but also the quality of the laser cut that the Co2 laser can achieve is exceptional.

In order to achieve the aforementioned high-quality laser cuts, the six axis robot is designed to follow pre-programmed paths, thus presenting each of the different variants to the laser head at the correct focal distance.

The laser source that is integrated as part of the RRTS14CC cell is generated from carbon dioxide and the integration of a series of mirrors means that the beam alignment from source to nozzle is both accurate and repeatable to suit the customer’s application. Though the RRTS14CC is a standard cell, the optics (tubes, mirrors etc.) will be specifically designed application by application to guarantee that the laser head arrangement is perfectly suited to the material that is being processed.

For more information on the RRTS14CC cell please visit its dedicated page here: http://cyan-tec.com/single-robot-laser-cutting-machine

 

Robot Laser Welding Cell is Flexible & Fast

To address the needs of the white goods and automotive industries in particular, expert system builder Cyan Tec Systems of Loughborough has developed a standard multi-axis robotic laser welding cell incorporating a 6-axis robot combined with a 2-axis tilt-and-turn manipulator to give the ultimate flexibility with 8 programmable axes. Such a system can work on large components or assemblies and present them in such a way to reduce the complexity of the robot moves and compress the overall cycle time.

More and more welding tasks are becoming automated as the lack of availability of skilled and experienced manual welders, and the requirements to achieve stringent and repeatable quality and higher throughput, drive production away from conventional joining processes towards laser welding.  In addition to this, the current trend in reshoring production from abroad promotes a high degree of automation which minimises the impact of international differences in labour rates, and reduces the cost and uncertainty associated with long distance logistics via sea or air freight.

The Hyperion MAR30WF is a standard system built by Cyan Tec using a 6-axis robot carrying a compact laser welding head from a multi-kW fibre laser source. The tilt and turn manipulator has an integral indexing system allowing parts to be safely unloaded and re-loaded during the welding cycle by an operator outside the Class 1 safety enclosure. Welding by laser is a non-contact process, where the laser beam is typically some distance from the final focusing optic. For best results a pipe delivers Argon assist gas which prevents oxidisation, leaving a bright and oxide-free weld which is capable of coating or painting after welding without any need for post-weld cleaning.

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Image: Standard Multi-axis robot laser welding cell

A highly efficient laser welding cell can be modified to process new products by simply re-programming the software and re-tooling for new configurations. Using a dedicated cell with a standard design gives the benefit of reduced cost and lead time for the capital equipment, as custom machinery is limited to the final tooling and the welding path programme.

Laser welding has the benefits of low heat input and excellent repeatability.  The accuracy and consistency reduces the amount of material required in flanges and enables novel joint arrangements since only single-sided access is required (unlike resistance spot welding).

Modern robots are faster, with higher accuracy and repeatability than previous generations. Cyan Tec has experience of integrating robots and lasers from all the major suppliers and can offer expert advice on the most appropriate solution for laser processing, paint spraying, assembly, test as well as many other applications. Standard and bespoke systems are offered with a full service from design through manufacture, a large installed base worldwide is supported by a dedicated team of engineers.

Shaping The Future of UK Joining Technology

Following the installation of Cyan Tec Systems’ laser processing system which includes the UK’s most powerful laser at the Manufacturing Technology Centre (MTC) in Coventry in 2014, the advanced laser welding and cutting robot cell is being used by industrial partners of the MTC to advance manufacturing processes and improve efficiency. Rolls Royce, a founding member of the MTC and major user of the laser system in Coventry, has completed a project to replace resistance welding with laser welding in the manufacture of titanium fairings for its advanced aircraft engines.

Working with laser welding experts at the MTC, Rolls Royce has successfully completed a programme to improve consistency, increase throughput and reduce manual input in the manufacturing process. The laser welding cell at the MTC is equipped with a range of welding and cutting head options and is capable of handling large and heavy parts with ease – the laser processing head being carried on a 6-axis robot, which is integrated with a multi-axis manipulator.

 

laser welding robot cell

Image: The laser processing cell supplied to the MTC by Tec Systems

Welding titanium by laser can achieve excellent results as long as the correct shielding with argon is provided. The MTC designed and manufactured assembly tooling with integral shield gas delivery. After qualifying the weld process, using fatigue test coupons, full scale laser welded parts were produced on the Cyan Tec robot cell.  These parts proved that laser welding produced less distortion than the existing resistance welded assembly.

Having extensive experience in the integration of lasers with robots and CNC machines for welding, cutting, marking and drilling, Cyan Tec is well-placed to provide turnkey laser systems for the development of new processes and the mass production of proven assemblies using automation, lasers and custom manipulation.

Cyan Tec has experience of integrating robots and lasers from all the major suppliers and can offer expert advice on the most appropriate solution for laser processing, paint spraying, assembly, test and other applications.  Standard and bespoke systems are offered with a full service from design through manufacture, a large installed base worldwide is supported by a dedicated team of engineers.