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by Dr David Maddison INDUSTRIAL ROBOTS Industrial robots are used to increase manufacturing efficiency, speed and precision and to remove people from repetitive and dangerous tasks. They can even perform jobs that a human would find impossible to do. T he word “robot” was coined by the Czech play- Babbage’s Difference Engine but these do not fit the above wright Karel Capek (1880-1938) who introduced it criteria. By this definition, many commonly consider that the in his hit play of 1920, R.U.R. or Rossum’s Universal Robots. It is derived from an old Slavonic word meaning first industrial robot that was actually built (which was “servitude,” “forced labour” or “drudgery.” You can listen also regarded as the first “pick and place” robot) was by an to a recording of this play at siliconchip.com.au/l/aaap Australian/Canadian “Bill” Griffith P. Taylor using a MecA student production of the play can also be seen at cano set in 1935-1937, the basic description was published “Rossum’s Universal Robots – Karel Capek - English Sub- in The Meccano Magazine of March 1938 (see opposite). The robot would pick up wooden blocks and then set them titles” siliconchip.com.au/l/aaaq An industrial robot is defined by the International Organi- down in a programmed sequence in certain patterns such as zation for Standardization in ISO 8373 as an “automatically a wall, dam or breakwater. The program was stored in the controlled, reprogrammable, multi-purpose manipulator, form of a punched paper tape and when electrical contact programmable in three or more axes, which can be either was made through a hole it operated a control to move in a fixed in place or mobile for use in industrial automation certain direction. The robot could also be controlled manually via control levers which were effectively what are operapplications”. (See siliconchip.com.au/l/aaax). There are other definitions for various robots but they ated when the machine is under automatic control. There were no electronall emphasise the characteric components apart from istics of multi-functionality SHORT LINKS five solenoids. It used 4000 and reprogrammability. In this feature, we have converted all the URLs to washers, 300 collars, 200 There have been other pro- “SILICON CHIP Short Links” to save you the hassle of gears and 100 pulleys from grammable machines such typing out website or YouTube names up to three lines long! as the Jacquard loom first Clicking on these short links when viewing SILICON CHIP online Meccano, along with a very small number of non-Mecdemonstrated in 1801, mu- (or entering the short link into your browser) will take you cano parts. sic boxes, the pianola and directly to the appropriate website. 18  Silicon Chip siliconchip.com.au A description of “Robot Gargantua”, accepted by some as the first industrial robot, designed by a Canadian/Australian. This page is reproduced from the March 1938 “Meccano Magazine”. siliconchip.com.au May 2017  19 Robot Gargantua’s control unit. Note the counters which indicate the number of driveshaft revolutions and which are used when programming the robot. Note also the punched paper tape holding the program. Photo by Peter Haigh. Robot Gargantua, as reproduced by Chris Shute of Wem, Shropshire, England. The control unit is at the left. Photo by Peter Haigh. Program sequences could be up to three hours long. The programmer had a number of counters which indicated the number of drive shaft revolutions – this number defined the position of the crane when writing the programs. Griffith P. Taylor submitted detailed documents to Meccano about this robot in 1938. They were also published much later (in 1995) in a 70-page book called “The Robot Gargantua (A Constructor Quarterly Special Publication)”. It was available (used) from Amazon at the time of writing or as a much cheaper digital download at siliconchip. com.au/l/aaas A detailed account of the robot was published by Chris Shute and can be accessed at siliconchip.com.au/l/aaay An early spray-painting robot was patented by Willard Pollard Jr. The patent was filed in 1934 and granted in 1942. Programming was done on a perforated film, the hole density of which was proportional to the speed of the controlling motors. The patent for this can be seen at siliconchip. com.au/l/aaaz This machine was licensed to the DeVilbiss company in 1937, before the patent was granted and in 1941 they completed the first prototype machine under the leadership of Harold Roselund. He also patented a robot in 1944 using the control mechanism of the Pollard machine but not the mechanicals. See “Means for moving spray guns or other devices through predetermined paths” at siliconchip. com.au/l/aab0 However, there seems to be no evidence that these machines were ever commercialised. Another early robot, described in a patent, is for a programmable arm for spray painting. This was invented by Willard L.V. Pollard (the father of the above inventor) and 20  Silicon Chip Illustration from US Patent 2286571 (1942) for Willard L.V. Pollard’s “Position-Controlling Apparatus” for spray painting applications. It seems odd seeing an old style car body being spray painted by a modern-looking industrial robot. However this machine was never built. siliconchip.com.au Build your own robot arm An open source robot arm for Arduino or Raspberry Pi called MeArm is available at siliconchip.com.au/l/aab2 Another open source robotic arm called uArm for Arduino is available at siliconchip.com.au/l/aab3 There are huge numbers of other commercial robot arm kits available, including from Australian suppliers such as Jaycar at siliconchip.com.au/l/aab4 or look on Google and Ebay. Illustration from Cyril Walter Kenward’s patent showing an implementation of the device with two robot arms mounted on a carriage. It was a remarkably advanced idea for the time. ence and synchronisation signals. The device was hydraulically operated and also had grippers which could be replaced with other fittings to suit the job at hand, just like modern robots. The patent even talked about using the robot to reproduce itself “The apparatus may be set up to assemble parts used in its construction and substantially or partially reproduce itself in this manner provided it is supplied with its component parts and tools required for the assembly operations.” Details of Kenward’s patent can be seen at siliconchip. com.au/l/aaav The first commercial industrial robot the patent was filed in 1939 and granted in 1942. The desired motion was recorded on a grooved cylinder and read by phonograph pickups. This robot was never built. The patent can be viewed at siliconchip.com.au/l/aaax British inventor Cyril Walter Kenward filed a patent in 1955 (awarded in 1957) entitled “Improvements in or relating to positioning, assembling or manipulating apparatus”. This device seemed very advanced for its time but there were no backers for it and it was not commercialised. Kenward’s robot could be taught by moving it through the desired motions which were recorded. One of the proposed recording methods was magnetic tape and the patent mentions the signal modulation techniques that could be used to record multiple channels of data, along with refer- The first commercially produced general-purpose industrial robot is credited to George Devol. He applied for a robotics patent in 1954 (awarded in 1961). Entitled “Programmed Article Transfer”, it can be seen at siliconchip. com.au/l/aaaw In the patent, Devol wrote that “The present invention makes available for the first time a more or less general purpose machine that has universal application to a vast diversity of applications where cyclic control is to be desired; and in this aspect, the invention accomplishes many important results. It eliminates the high cost of specially designed cam controlled machines; it makes an automatically operating machine available where previously it may not have been Described as the world’s first commercially produced general-purpose industrial robot, the Unimate serial #001 by Unimation Inc., photographed in 1961 as it was being prepared for shipment from the manufacturer to the GM die-casting plant in Trenton, New Jersey. It shows Unimation president Joe Engelberger (in bowtie) and engineers George Munson and Maurice Dunn. However, in the author’s opinion, this might be a prototype from 1959 as other versions of this robot look slightly different. The robot on the right appears to be the one that was actually installed in the GM die-casting plant. It is now at the Ford Museum, Greenfield Village, Michigan (see siliconchip.com.au/l/aab1). It is assumed that the picture from the museum is authoritative. siliconchip.com.au May 2017  21 Robot safety Industrial robots are powerful, fast-moving and possibly unpredictable machines. Like any industrial or other machine, special precautions need to be made to protect the safety and lives of people working close by. An August 2014 article in Wired magazine cited a New York Times article that said that over the last 30 years, 33 people had died in industrial accidents in the US associated with robots. While any death is tragic, these accidents are not really any different to a wide variety of other industrial accidents and result from similar mistakes and oversights. The first person to be killed in an accident with a robot was Robert Williams of the USA, in 1979. Some typical precautions to prevent accidents with industrial robots involve safety fences, with switches on gates and light beams to shut the machine down if there is an intrusion into the robot’s space as well as limit switches and software to prevent the robot moving into forbidden areas. As with all safety systems, there should be multiple levels of redundancy. The robot should also have safety systems to prevent its own destruction even economical to make such a machine with cam-controlled, specially designed parts; it makes possible the volume manufacture of universal automatic machines that are readily adaptable to a wide range of diversified applications; it makes possible the quick change-over of a machine adapted to any particular assignment so that it will perform new assignments, as required from time to time. It can be seen that cyclically operated machines heretofore controlled manually can now be made automatic; and universal transfer machines can be supplied and adapted readily for special applications of the purchaser, and the purchaser, in turn, can stock such machines which he can adapt quickly and easily to new requirements from time to time.”. The Unimate (UNIversal autoMATION) robot was developed out of Devol’s patent. It followed instructions stored on a magnetic drum, to move and stack pieces of hot die-cast metal. Die-cast work was the first “killer app” for industri- if there are software errors in its programming. Such systems would include those that prevent it picking up an excessively heavy load or trying to move into a position that it is not physically possible. Some safety videos on robot safety can be seen at: “ABB Robotics - Safe human robot interaction – SafeMove” via siliconchip.com.au/l/aab5 “Robot Safety: Robot Reality 1990 National Institute for Occupational Safety and Health” siliconchip.com. au/l/aab6 (from 1990 but entertaining). al robots as it involved the movement of hot, often heavy pieces of metal in a potentially dangerous environment. The first Unimate worked in a polar coordinate system and had five axes of control. A number of technologies had to be developed for this robot, including digital control, non-volatile memory, optical encoders to determine shaft position, digital servo control, hydraulic servo control and electrical and hydraulic power supplies. Both Unimate and another company, AMF, were later found to have infringed Cyril Walter Kenward’s patent (which was never commercialised) and the matter was settled with a cash payment. Industrial robot applications Typical applications for industrial robots are assembly, coating, deburring, die casting, laboratory automation, moulding, material handling, picking, palletising, packaging, painting, picking and placing parts, selecting and sort- (Above): basic elements of a serial robot and a parallel robot A serial robot is the most common type of industrial robot and it has just one kinematic chain that connects the base to the end effector. A robot arm, the classic type of industrial robot is an example of a serial robot. The movement of any actuated joint controls the whole remaining arm beyond that joint in the direction toward the end effector. (Right): a representation of a typical serial robot in the form of a manipulator arm or articulated robot showing six axes. Axes A1 through A3 allow motion in space similar in human terms to a shoulder, bicep and forearm and axes A4 through A6 allow for motion, known as pitch, roll and yaw equivalent to that of the wrist. 22  Silicon Chip siliconchip.com.au Mechanical elements of a parallel robot supporting a platform. U-joint stands for universal joint and P-joint stands for prismatic joint, a type of sliding linkage. This example has three kinematic chains but a flight simulator contains six. ing, transportation, warehousing and welding. Among the ultimate objectives are to lower costs, to increase flexibility in manufacturing processes and the variety of end products, improve quality of manufactured products and to enable work to be done that is hazardous, difficult or impossible for a human to do. Configurations of industrial robots A majority of industrial robots are considered “manipulators” which are roughly equivalent mechanically to a combination of the human arm and hand, along with a sensory and control system. All robots generally have three main sub-systems: a motion system which is the physical structure to enable the robot to move; a recognition or sensory system to keep track of the robot’s motion and position in space and to also sense and track objects it may be required to manipulate and a control system in the form of a programmable computer (or other type of controller on earlier robots). A number of parameters are used to describe, control and The four basic types of serial robot arm configurations, their range of movement and representations of the work spaces they can access. There are some variations of these basic layouts. Even though the cartesian robot is a serial type, it is also called a linear robot by some. siliconchip.com.au One type of end effector of an industrial robot. In this case it is a gripping device to pick up coloured blocks. Note the camera for the vision system of the robot. program a robot. These include the number of axes (usually the same as the degrees of freedom), the kinematics or physical arrangement of the robot structure that gives it motion, the working envelope of the robot, ie, what physical space it can reach, how much weight the robot can carry or lift, how fast the robot can move and accelerate and how accurately the robot can be located in space and how reproducible its positioning is. Other parameters are the type of motion control (which might be simple such as picking up an object in one place and placing it down in another or it might require continual control of motion such as in welding or spray painting operations), its power source (electric or hydraulic) and its drive mechanism (gears or direct drive). At the highest level of robot architecture, robots are also classified as either serial or parallel in nature. Regardless of which group the robot is a member of, it has three main mechanical parts. It has a stable, usually fixed base, a “kinematic chain or pair” which is made of a series of rigid bodies called “links” connected by a number of actuated “joints” and an “end effector”, which is the part of the robot that interacts with the environment and may be a gripping mechanism to pick up parts or a welding head, for example. A serial robot is the most common type of industrial robot and it has just one kinematic chain that connects the base to the end effector. A robot arm ( the classic type of industrial robot) is an example of a serial robot. The movement The ONExia ONEreach cartesian robot. May 2017  23 The four basic configurations are cartesian, cylindrical, spherical (also known as polar) and articulated (also known as revolute). The robot end effector The end effector is the tool at the end of a robot arm that enables it to interact with the work piece it is intended to manipulate. It could be something to lift up a work piece such as a gripping device or suction device or it could be a tool to do work on a piece such as a welding head or a device to apply sealant or paint. The Hudson Robotics PlateCrane EX cylindrical robot for laboratory use. It moves test plates from the black structure on the right and places them in the analyser on the left. of any actuated joint controls the whole remaining arm beyond that joint in the direction toward the end effector. A parallel robot, or parallel manipulator, has more than two kinematic chains connecting the base to the end effector. This robot can have either an end effector at its working end or be terminated as a platform. The spray painting robot described above in US Patent 2213108 is an early example of a parallel robot. A modern example of a parallel robot architecture is the hexapod positioning system as used on a flight simulator which is supported by six kinematic chains or actuators. One estimate is that there are one million industrial robots in use in the world, most of them being of a serial nature, with about 50,000 parallel robots in use. There are four basic configurations or geometries of a serial industrial robot plus additional variations of these. Robot vision Robot vision is an increasingly important part of a robot’s senses. Vision enables a robot to detect randomly oriented and located parts and pick them up, rather than the alternative method of parts being kept in precise locations with fixtures, guides and jigs. Examples of robot vision can be seen at “ABB Robotics - Integrated Vision” siliconchip. com.au/l/aab7; “Robotic Vision” via siliconchip.com.au/l/ aab8; “Vision Guided Robot – Universal Robots UR5” at youtu.be/w7-KGaYGuMA;“Vision Guided Robot System” siliconchip.com.au/l/aaba (silent) and “Small company, big vision – robotics help to keep Dutch bakery profitable and flexible” at siliconchip.com.au/l/aabb Although not discussed in the last video, it shows how robot vision is used to pick up randomly located cookies from a conveyor belt. Some current examples of industrial robots A cartesian robot moves its axes in a linear manner at right angles to each other rather than by rotation. These An advanced dual arm articulated robot. This is ABB’s YuMi. It is a “collaborative” robot, designed to work alongside humans in assembly processes. It does not need a cage or other barriers as it is inherently safe with a soft body covering and numerous sensors to detect the presence of humans. For a video of this robot, see “Introducing YuMi, the world’s first truly collaborative robot - ABB Robotics” at siliconchip.com.au/l/aabe 24  Silicon Chip siliconchip.com.au A Mitsubishi SCARA robot. Mechanical representation of SCARA robot. It has two axes of rotation plus a range of vertical motion in the Z direction. Inset at top is the kidney-shaped work envelope of SCARA robot. (Diagrams: Project Lead the Way.) types of robot are often used as milling machines and 3D printers (although some would argue whether those are true robots or not). Another application for a cartesian robot is picking items such as boxes off a conveyor belt and stacking them. A video of the ONExia ONEreach cartesian robot can be seen at “No Programming Required – ONEreach Cartesian Robot” siliconchip.com.au/l/aabc An example of cylindrical robot is the Hudson Robotics PlateCrane Ex which according to the manufacturer is optimised for loading and unloading automated lab instruments, such as readers, microplate washers and reagent dispensers. A video of the robot in action can be seen at “PlateCrane with HyperCyt.wmv” siliconchip.com.au/l/aabd Spherical or polar robots are similar to cylindrical robots but use polar coordinates rather than cylindrical coordinates to describe their range of motion. They have two rotary joints and one linear actuator. They are not in common use now and an important example was the Unimate OC Robotics snake arm robot. siliconchip.com.au robot which was the first commercial industrial robot and which was mentioned above and the Stanford arm from 1969. This early type of geometric configuration was good for being able to be programmed with the control hardware available at the time. Articulated or revolute robots are among the most common and familiar type of industrial robot. They mimic the form of the human arm. They have at least three rotary joints plus typically three additional rotary joints for a “wrist”, “hand” and “forearm” where fitted. Pitch moves the wrist up and down, yaw moves the hand left and right and roll rotates the forearm. See earlier diagram of a typical serial robot. SCARA SCARA stands for “Selective Compliance Articulated Robot Arm’” and a SCARA robot has two axes of rotation plus linear motion (usually vertical) in one direction. When fitted with a wrist joint, it can also have additional ranges of motion. Typical applications are “picking and placing” of parts, many types of assembly operations, application of sealant and handling of machine tools. Their basic range of motion through their two rotational axes is equivalent to the motion of one’s shoulder and elbow with the arm held parallel to the ground. They are good for high speed assembly operations, repeatability of positioning, good payload capability and large workspace. The black snake-like object is OC Robotics snake arm robot used for inspection of a nuclear power plant. May 2017  25 Fanuc “flying robots” in action. They are considered to be seven-axes robots. They were developed in Japan and they were announced in 1981 by Sankyo Seiki, Pentel and NEC. For videos of SCARA robots in action see “MITSUBISHI ELECTRI SCARA ROBOT RH-6SH RH-6SDH” at siliconchip.com.au/l/aabf and “Adept Cobra SCARA” at siliconchip.com.au/l/aabg Snake robots A snake arm robot is a new type of robot that is in the form of a continuously curving manipulator arm and is equivalent to a snake or elephant’s trunk in terms of its mechanical behaviour. These robots are primarily used for access to confined spaces such as in industrial inspection applications or surgery. They are driven by a system of “tendons” or multiple actuators. For videos of some snake arm robots in action see “OC Robotics – Snake arm 101” at siliconchip.com.au/l/aabh and “OC Robotics – Introducing the Series 2 - X125 system” at siliconchip.com.au/l/aabi An example of a parallel architecture robot in current use is the Adept Quattro s650h parallel robot. Claimed to be the world’s fastest industrial robot, it is designed for packaging, manufacturing, assembly and material handling. It is said to be the only parallel robot or “delta robot” with a four arm design. Some videos of this robot in action can be seen at “Adept Quattro Robot” siliconchip.com.au/l/aabj and “Omron Adept Quattro Confection Application” at siliconchip. com.au/l/aabk and also at siliconchip.com.au/l/aabl Flying robots The Fanuc “flying robot” is a conventional robotic arm or arms mounted on a rail system to enable them to move up and down an assembly line. They can, for example, pick up a part from one machining centre and take it to the next machining centre. A flying robot can be seen in operation in a camshaft manufacturing operation at “FANUC R-2000iB “Flying Robots” in Camshaft Machining Center – Courtesy of TranTek Automation” siliconchip.com.au/l/aabm and siliconchip. com.au/l/aabn Mobile industrial robots The MiR100 robot doing its rounds in a healthcare setting to deliver medical products to nurses and patients. Inset: the MiR100 can be controlled from a tablet computer. 26  Silicon Chip Mobile industrial robots have applications in healthcare where they can be used to deliver drugs or other supplies from a central storage; in aircraft maintenance for painting siliconchip.com.au Robot languages The first industrial robot described in the patent by George Devol in 1954 did not have a programming language as such, but was programmed by moving it to desired positions in the desired sequence and having the controller record those positions in memory. In operation, the controller could replay the desired sequence of positions from memory, faithfully replicating the original movements. Most industrial robots today can also be programmed in this manner if desired. This is a particularly useful method for, say, recording and replicating a spray painting pattern, from a master painter. There are two main generations of robot programming languages. The first genera- Programming with ABB RobotStudio, a high level graphical programming tion was characterised by “programming by and simulation software for ABB robots. Also see video “ABB robot teaching”, the second generation by “robot- studio for beginners” at siliconchip.com.au/l/aabs oriented programming”. In the 1970s, industrial robots were programmed with first generation industrial roEnglish, as follows: bot languages, some of which were derivatives of traditional languages first developed in the 1950s such as ALGOL or FORTRAN Move to P1 (a general safe position) that interfaced with the robot at a low level. Move to P2 (an approach to P3) There were also proprietary languages such as SIGLA (SIGma Move to P3 (a position to pick the object) LAnguage by Olivetti, 1974), ROL (RObot Language, 1976), Funky Close gripper (by IBM, 1977) and SERF (Sankyo Easy Robot Formula, 1978) as Move to P4 (an approach to P5) well as a language developed at Stanford University called VAL Move to P5 (a position to place the object) (VicArm Language from 1973, later to be adopted by Unimation Open gripper in 1977). Move to P1 and finish These first generation languages were mainly oriented toward “programming by teaching”. As with the first UNIMATE, the proThe English description is translated to an early generation grammer guides the robot arm by hand or with a control box to language VAL: the desired position and the computer records these movements. PROGRAM PICKPLACE The computer then generates the appropriate code which can 1. MOVE P1 later be modified as necessary. These languages were suitable 2. MOVE P2 for robot applications involving spray painting, spot welding and 3. MOVE P3 stacking of items. 4. CLOSEI 0.00 In the 1980s a second generation of industrial robot languag5. MOVE P4 es was developed. These were high level languages with a struc6. MOVE P5 tured programming environment. Typical instructions of high 7. OPENI 0.00 level languages are present such as logical branching and loops. 8. MOVE P1 This second generation of languages included much more so.END phisticated control of the robot, opportunities for sensor inputs, the ability of robots to communicate with one another and some Here the program is translated into a later generation language artificial intelligence. Stäubli VAL3. Note the instructions for speed and absence of The languages also included mathematical models of the ropoints P2 and P4. These intermediate locations are unnecessary bot to ensure it can be moved in the most efficient and smooth since the trajectory from the start to the end point is computed manner possible. The second generation languages can program by the software: sophisticated applications such as where sensor input is required and coordination and cooperation with other robots. begin There is not yet any real third generation of languages but rather movej(p1,tGripper,mNomSpeed) new ideas in programming, such as task oriented-programming to movej(appro(p3,trAppro),tGripper,mNomSpeed) give instructions similar to what would be given in object-oriented movel(p3,tGripper,mNomSpeed) programming like “move that box over here” without the details of close(tGripper) how this is to be done. To do these sort of tasks the robot would movej(appro(p5,trAppro),tGripper,mNomSpeed) have to understand its environment. movel(p5,tGripper,mNomSpeed) Most robot manufacturers have their own proprietary languages open(tGripper) but they are roughly similar to one another. movej(p1,tGripper,mNomSpeed) A simple program (from Wikipedia) might be described in end siliconchip.com.au May 2017  27 and repairs; and in industrial production where they can be used for materials transport around warehouses and from production lines, which may themselves be automated. MIR (siliconchip.com.au/l/aabo) makes a popular mobile industrial robot called the MiR100. It navigates by being able to identify its driving area with a variety of laser, ultrasonic and 3D visual sensors or by using a 3D model of the building in which it operates. It weighs 62.5kg, can operate for about 10 hours or move a distance of 20km on a charge, carry 100kg or tow 300kg and it has WiFi, Bluetooth, USB and ethernet communications. The robot can be operated by any smartphone, tablet or PC. Here are some videos of MiR100 in action: firstly, at a power supply company “Magna-Power” siliconchip.com. au/l/aabp and secondly in a healthcare application where it is used to deliver pharmaceuticals to patients “MIR Sønderborg Case (English)” siliconchip.com.au/l/aabq Air-Cobot (Aircraft Inspection enhanced by smaRt & Collaborative rOBOT) is a robot under development by French companies. It is intended for visual inspection of aircraft on the runway before take-off or in a hanger. Its computers (one running Linux and the other Windows) contain a virtual model of a given aircraft model and navigate to preset points to inspect them. The robot employs autonomous navigation based on GPS and sensors such as laser range-finders to create situational awareness, as well as a virtual model of the environment (eg, airport parking area or hangar). The robot uses image analysis to detect defects in items such as turbine blades or tyres. A video of this robot can be seen at: “Air-Cobot” See siliconchip.com.au/l/aabr Now becoming much more widely used, surgical robots are associated with minimally invasive surgery through a small incision, high accuracy, a moderation of any unwanted movements of a surgeon’s hand and the possibility of remote control of surgical procedures. Air-Cobot about to perform an inspection on an Airbus A320. Inset at top is a possible inspection pattern around the aircraft. Note that special precautions need to be made against hackers and issues of internet latency. The first surgical robot was introduced in 1985. SC Want to build a bridge? Let your robots do it for you, as this footbridge in Amsterdam shows during construction in this artist’s conception” (See siliconchip.com.au/l/aabv). 28  Silicon Chip siliconchip.com.au