Safety Options for Robotic Systems

Safety equipment is an essential part of any robotic system or workcell to ensure the protection of your workers while your robot is in motion. There are a variety of safety options on the market today that will keep workers safe.

Fencing, Arc Glare Shields, and Dividers

Keeping people safe is a top priority when working with industrial robots, especially in tasks like welding, cutting, or material handling. One of the most effective ways to keep employees safe is to use protective measures throughout the work area.

Fencing

Fenc­ing pro­vides a phys­i­cal bar­ri­er that clos­es off the area around the robot itself, allow­ing peo­ple to see the set perime­ter of the work cell or sys­tem. These cages are sev­er­al feet tall, and their design depends on the appli­ca­tion and how much area needs to be safeguarded.

Fenc­ing may also be cov­ered with cur­tains to keep debris from being thrown out­side the perime­ter of the work cell or sys­tem. Some cur­tains pro­tect against debris, and oth­ers pro­tect from arc glare.

Arc Glare Shields

Arc welding produces intense ultraviolet (UV) and infrared (IR) light radiation that can cause serious retinal damage, eye irritation, and skin damage to anyone exposed, even indirectly. Weld­ing shields are typically made from tinted or specially coated materials that reduce glare while still allowing for visibility into the workspace, in a way similar to how a pair of sun­glass­es protects your eyes.

Arc glare cur­tains, like Wil­son Spec­tra cur­tains, are avail­able in shades of yel­low, orange, grey, and brown, and are usu­al­ly fixed to the three sides of the work cell fenc­ing. This safe­ty option will absorb, fil­ter, and scat­ter the light from the arc weld, reduc­ing the glare and improv­ing the work­ing industrial environment for every­one in a weld­ing shop.

Dividers

Unlike arc glare shields, which are par­tial­ly trans­par­ent, met­al dividers work in a dif­fer­ent capac­i­ty to pro­tect a worker’s eyes from the impact of arc glare. When a 180-degree index­ing table is fixed inside the sys­tem, it has a tall, ver­ti­cal met­al divider fixed in the cen­ter of the table, which blocks the robot operation from the oper­a­tor. This not only pro­tects the eyes from arc glare, but also from weld spray.

Light Curtains and Area Scanners

Fencing tends to have three sides, with one area open for loading parts. This area needs a different set of robotic safety options, like light curtains or an area scanner.

Light curtains have an emitter and receiver that sit across from each other. Once the light curtains are lined up and functional, they send an invisible beam across the area and give the robot a signal that it is okay to operate. If this area is invaded, the light curtains send a signal to the robot to stop. This is caused by a break in the fence circuit between the robot and the light curtains. When the fence circuit is broken, the robot can still be moved with a teach pendant.

SICK makes a variety of light curtains used by Robots.com in several of their work cells and robot systems. According to SICK Sensor Intelligence, safety light curtains are a cost-effective way to protect the access point for your robot system entry point. They come in several different sizes, from compact to robust, and even have different resistance variants.

An area scanner is similar to light curtains. However, instead of having one specific area where light is transmitting from an emitter to a receiver, an area scanner is a small device that can scan an entire area. SICK also makes area scanners, and their scanners are programmable, allowing companies a high level of performance that can work for a variety of applications. Since they can be programmed, area scanners have a higher level of versatility than light curtains, because they can have a more precise area muted out (a loading zone for example), making it easier to load and unload parts in a particular system or work cell.

Emergency Stop (E-Stop)

Emergency stop, or e-stop, is a function used in case of an emergency. There are usually one or more e-stop buttons around a robotic work cell or system, and these buttons cause the robot to stop motion immediately. Unlike the fence circuit, when the e-stop circuit is broken, the robot is unable to be moved at all, even with the teach pendant.

Whenever something breaks the e-stop or fence circuit for a robot system, the safety reset light will come on. This light is usually located at the operator station. Once you have corrected the safety situation, the operator can press the safety reset button and then press start to resume operation. If the safety situation has not been corrected, the reset will not work, and the system will not work until the situation is corrected.

Safety Requirements for Industrial Robots

Industrial robots have become an everyday part of modern manufacturing, allowing automation, improving precision, and increasing productivity. However, they pose significant safety risks, especially when humans work in or near robotic systems. To enforce safe operation, companies are now required to comply with a framework of occupational safety regulations, technical guidelines, and best practices.

OSHA Safety Requirements

Safety equipment, like that featured above, is required under the OSHA directive regarding robotic safety protocols. OSHA Directive STD 1-12-002 states that one or more of these safety methods, be it barrier guards or electronic safety devices, shall be provided to protect the operator and employees from potential hazards of operation, such as flying chips, sparks, rotating parts, etc.

U.S. Robotics Safety Standard

In 2012, the American National Standards Institute and Robotics Industries Association (RIA) completely reassessed and rewrote their standard practices for safety when dealing with industrial robot applications. One of those changes was to the functional safety guidelines for robotics.

According to ANSI/RIA R15.06:2012, companies must perform risk assessments on their integrated systems and work cells and ensure that they are outfitted with a functional safety design to reduce risk to users.

ISO Standards

The ANSI/RIA standard draws heavily from the following International Organization for Standardization standards. These ISO standards are considered the global benchmarks for safety in industrial robotics:

• ISO 10218-1:2011 – This standard specifies the safety requirements for industrial robots and robot systems, focusing on design and construction for safety during use.
• ISO 10218-2:2011 – This standard applies to integrating robots into systems or work cells, detailing requirements for system integrators and users for overall safety.
• ISO/TS 15066 – This technical specification expands upon the ISO 10218 standards, providing additional guidance for collaborative robot safety (cobot) applications, especially where human workers and robots share the same workspace.
  

Find the Right Safety Parts With Robots.com

If you're exploring safety options for your automation system but aren't sure which parts are right for your application, our team is here to help. With decades of experience integrating safeguarding solutions, our specialists can guide you in selecting the most effective options to keep your system running smoothly and securely.

Difficulty choosing the right safety options for your system? Call us at 877-762-6881 or fill out a contact form here to get in touch with a specialist.