Automation Systems And Product Liability: Best Practices

Contemporary theater depends increasingly on the "wow" factor. General audiences are no longer satisfied to see a great performance live without an associated visual spectacle supporting the performer. With that comes increasing danger to actors, dancers, artists, musicians and stage technicians.

Recent accidents involving actors and stagehands, on and off Broadway, attest to this. In Broadway productions of "The Little Mermaid" and "Spider-Man Turn Off the Dark," actors were injured; recently in Las Vegas, a stagehand fell into a two-story loading pit. While automation systems and their integration into equipment and scenery may be developing in complexity, fundamental principles of product liability still apply.

This article details certain "best practices" that may serve to mitigate exposure to liability for the provider or user of an automation system.

Automation Systems

Theatrical automation systems consist of a complex assembly of technologies. Generally, they consist of a software component (Graphical User Interface or GUI), with which the motion profiles are created to control an electrical or electronic component that in turn regulates and distributes a power source (electrical, hydraulic and pneumatic) to a mechanical or power transmission device, such as an electric motor or a hydraulic piston.

Provision of electricity itself has been held not to be a product, but software may be.1 While software is found throughout the automation system on embedded controllers in the electronic components, it is the GUI software that is the main focus in limiting product liability exposure. It is here within the GUI that the producer of the show is able to program the cues that manipulate movement of the scene changes and thus set the stage of the producer's final product.

Four general steps create motion with an automation system: First, the commands are entered at the control desk or console. Second, these commands are transmitted from the user interface on the computer to a motion controller, programmable logic controller (PLC) or intelligent drive. Third, the motion controller, PLC or drive converts the motion profile data to an output signal that powers the electromechanical, pneumatic-mechanical or hydromechanical device. Fourth, through the mechanical power transmission equipment is the actual physical movement of the scenery.

In short, the automation system coordinates the necessary information to convert the profile data from the GUI on the operator's computer into actual motion.

The software component has two aspects. First is the executable program provided by the supplier that may be "off the shelf," which may contain the automation system's proprietary elements with regular updates available to all purchases of the program or that may be customized and specifically developed for a particular user.

Second is the user input file created through the use of the executable program, i.e., the cues that are entered. The analogy would be a word processing program, which the user uses to create content in a particular form using the program. This distinction is key when it comes to analyzing fault and cause of the accident, i.e., whether the actual software program is defective or whether it has been negligently used or otherwise misused or whether the resulting set of cues have not been properly executed.

Automation may take one of two basic forms. The first is pure automation, in which a single...