PLC Manufacturer Rankings

After spending the last couple of weeks teaching PLC programming, I decided to do a little research on the popularity of the different manufacturer’s platforms worldwide. I have been asked many times in the past who the biggest, most popular, “best” PLC manufacturer is and I try not to inject my own preferences into the discussion. I have worked with 9 or ten different PLC platforms in the past and have recommended different platforms based on customer needs and budgets. I consider myself proficient in most of the major manufacturer’s platforms, with the exception of Modicon (in which I have little experience).

You would think that in the modern days of Google and other search engines that information like this would be fairly easy to come by. After all, with user groups in Linked In, online forums like control.com and surveys posted regularly by the manufacturers themselves such information should be readily available.

It is fairly easy to get information on the relative size of automation companies. Jim Pinto wrote a post in 2012 on the top 50 automation companies which used data from controlglobal.com’s 2011 list. This placed Siemens at the top spot worldwide with other major PLC manufacturer’s as follows:

1. Siemens
2. ABB
4. Schneider (Modicon)
5. Rockwell (Allen-Bradley)
7. Mitsubishi
8. GE
11. Omron
33. Bosch Rexroth
35. Beckhoff
37. Fuji
47. Toshiba

This list is missing some notable PLC manufacturers such as Keyence, Idec, Panasonic and Koyo. So how to drill down and analyze the PLC market by itself?

ARC Advisory Group is the leading global market research firm for automation, asset management, control, M2M, MES, PLM, SCM and software. Their most recent analysis of the market is available here. I have submitted a request for information as their pricing is not available online… I have a feeling it will be expensive. It is also unlikely that I can share it in any meaningful way without infringing on copyright laws.

A November 2001 survey by this group is available here. The results are out of date and 58% of the respondents were from North America, but it does provide an idea of what the market might look like today:

In North America Rockwell/Allen-Bradley had between 60% and 70% of the market share in both OEM and end-user markets. Siemens was a very distant second with 5% of the OEM market and 19% of end users, Schneider (Modicon) took the third spot with 5% of OEMs and 4% of end users. This left about 20% of the market in both the OEM and end-user categories for all other manufacturers combined.

In Europe Siemens had a much greater percentage of the market, especially among end-users. Much of the Allen Bradley presence among OEMs probably had to do with equipment imported from or designed by companies in the United States.

Modicon is not broken out in the European market but probably makes up a significant portion of the “other” category in the end-user market since they are a French company. Japanese PLC platforms such as Mitsubishi and Omron probably make up a major part of the other among OEMs.

In this survey a conclusion is drawn that Mitsubishi dominates the Japanese market. There is no data for this listed in the report but this is probably a valid assumption. Japanese engineers I have worked with in the past certainly seem to prefer it.

In my experience people often resent the biggest of these PLC manufacturers because of the cost of their products (especially software) relative to other platforms. The software licensing policies also make it difficult for engineers and technicians to obtain their own software for training and practice. Over the last couple of weeks I have had some good discussions with guys who work in the manufacturing environment every day. It was easy to pick up on some of the frustrations they have had with the ability to get support from manufacturers. In general people were pretty happy with the local vendors but less so with the manufacturers themselves. At the same time, when a company has mostly one brand of PLC in their plant there is little ability to do much about it.

Overall I remain somewhat brand-agnostic. What is best for most industrial manufacturers is usually whatever PLC they already use. I certainly have my preferences, but much of this is probably based mostly on familiarity and experience with the software and hardware.

Interpreting the brain signals for computer interface

BCI Applications

   

One of the most exciting areas of BCI research is the development of devices that can be controlled by thoughts. Some of the applications of this technology may seem frivolous, such as the ability to control a video game by thought. If you think a remote control is convenient, imagine changing channels with your mind.

However, there's a bigger picture -- devices that would allow severely disabled people to function independently. For a quadriplegic, something as basic as controlling a computer cursor via mental commands would represent a revolutionary improvement in quality of life. But how do we turn those tiny voltage measurements into the movement of a robotic arm?

Early research used monkeys with implanted electrodes. The monkeys used a joystick to control a robotic arm. Scientists measured the signals coming from the electrodes. Eventually, they changed the controls so that the robotic arm was being controlled only by the signals coming form the electrodes, not the joystick.

A more difficult task is interpreting the brain signals for movement in someone who can't physically move their own arm. With a task like that, the subject must "train" to use the device. With an EEG or implant in place, the subject would visualize closing his or her right hand. After many trials, the software can learn the signals associated with the thought of hand-closing. Software connected to a robotic hand is programmed to receive the "close hand" signal and interpret it to mean that the robotic hand should close. At that point, when the subject thinks about closing the hand, the signals are sent and the robotic hand closes.

A similar method is used to manipulate a computer cursor, with the subject thinking about forward, left, right and back movements of the cursor. With enough practice, users can gain enough control over a cursor to draw a circle, access computer programs and control a TV [source: Ars Technica]. It could theoretically be expanded to allow users to "type" with their thoughts.

Once the basic mechanism of converting thoughts to computerized or robotic action is perfected, the potential uses for the technology are almost limitless. Instead of a robotic hand, disabled users could have robotic braces attached to their own limbs, allowing them to move and directly interact with the environment. This could even be accomplished without the "robotic" part of the device. Signals could be sent to the appropriate motor control nerves in the hands, bypassing a damaged section of the spinal cord and allowing actual movement of the subject's own hands.

Robotic surgery

Robotic surgery is a method to perform surgery using very small tools attached to a robotic arm. The surgeon controls the robotic arm with a computer.

Description

You will be given general anesthesia so that you are asleep and pain-free.

The surgeon sits at a computer station and directs the movements of a robot. Small surgical tools are attached to the robot's arms.

• The surgeon makes small cuts to insert the instruments into your body.
• A thin tube with a camera attached to the end of it (endoscope) allows the surgeon to view enlarged 3-D images of your body as the surgery is taking place.
• The robot matches the doctor's hand movements to perform the procedure using the tiny instruments.

Why the Procedure is Performed

Robotic surgery is similar to laparoscopic surgery. It can be performed through smaller cuts than open surgery. The small, precise movements that are possible with this type of surgery give it some advantages over standard endoscopic techniques.

The surgeon can make small, precise movements using this method. This can allow the surgeon to do a procedure through a small cut that once could be done only with open surgery.

Once the robotic arm is placed in the abdomen, it is easier for the surgeon to use the surgical tools than with laparoscopic surgery through an endoscope.

The surgeon can also see the area where the surgery is performed more easily. This method lets the surgeon move in a more comfortable way, as well.

Robotic surgery can take longer to perform. This is due to the amount of time needed to set up the robot. Also, many hospitals may not have access to this method.

Robotic surgery may be used for a number of different procedures, including:

• Coronary artery bypass
• Cutting away cancer tissue from sensitive parts of the body such as blood vessels, nerves, or important body organs
• Gallbladder removal
• Hip replacement
• Hysterectomy
• Kidney removal
• Kidney transplant
• Mitral valve repair
• Pyeloplasty (surgery to correct ureteropelvic junction obstruction)
• Pyloroplasty
• Radical prostatectomy
• Radical cystectomy
• Tubal ligation

Robotic surgery cannot be used for some complex procedures.

Risks

The risks for any anesthesia and surgery include:

• Reactions to medicines
• Breathing problems
• Bleeding
• Infection

Robotic surgery has as many risks as open and laparoscopic surgery. However, the risks are different.

Before the Procedure

You cannot have any food or fluid for 8 hours before the surgery.

You may need to cleanse your bowels with an enema or laxative the day before surgery for some types of procedures.

Stop taking aspirin, blood thinners such as warfarin (Coumadin) or Plavix, anti-inflammatory medicines, vitamins, or other supplements 10 days before the procedure.

After the Procedure

You will be taken to a recovery room after the procedure. Depending on the type of surgery performed, you may have to stay in the hospital overnight or for a couple of days.

You should be able to walk within a day after the procedure. How soon you are active will depend on the surgery that was done.

Avoid heavy lifting or straining until your doctor gives you the OK. Your doctor may tell you not to drive for at least a week.

Outlook (Prognosis)

Surgical cuts are smaller than with traditional open surgery. Benefits include:

• Faster recovery
• Less pain and bleeding
• Less risk of infection
• Shorter hospital stay
• Smaller scars

Alternative Names

Robot-assisted surgery; Robotic-assisted laparoscopic surgery; Laparoscopic surgery with robotic assistance

References

Eichel L, McDougall EM, Clayman RV. Fundamentals of laparoscopic and robotic urologic surgery. In: Wein AJ, ed. Campbell-Walsh Urology. 10th ed. Philadelphia, PA: Elsevier Saunders; 2011:chap 9.

Fried GM. Emerging technology in surgery: Informatics, electronics, robotics. In: Townsend CM Jr, Beauchamp RD, Evers BM, Mattox KL, eds. Sabiston Textbook of Surgery. 19th ed. Philadelphia, PA: Elsevier Saunders; 2012:chap 17.

Hu JC, Gu X, Lipsitz SR, Barry MJ, D'Amico AV, Weinberg AC, et al. Comparative effectiveness of minimally invasive vs. open radical prostatectomy. JAMA. 2009;302(14):1557-64. PMID: 19826025 www.ncbi.nlm.nih.gov/pubmed/19826025.

Oleynikov D. Robotic surgery. Surg Clin N Am. 2008;88:1121-30. PMID: 18790158 www.ncbi.nlm.nih.gov/pubmed/18790158.