Sensors and gripper arms can simply be attached and removed as needed. You dont even have to be a specialist to quickly and easily replace a defective part, which makes the robots extremely flexible and economical to operate.
Evan Ackerman for IEEE Spectrum: As sensors, computers, actuators, and batteries decrease in size and increase in efficiency, it becomes possible to make robots much smaller without sacrificing a whole lot of capability. There’s a lower limit on usefulness, however, if you’re making a robot that needs to interact with humans or human-scale objects. You can continue to leverage shrinking components if you make robots that are modular: in other words, big robots that are made up of lots of little robots.
In some ways, it’s more complicated to do this, because if one robot is complicated, robots tend to be complicated. If you can get all of the communication and coordination figured out, though, a modular system offers tons of advantages: robots that come in any size you want, any configuration you want, and that are exceptionally easy to repair and reconfigure on the fly.
MIT’s ChainFORM is an interesting take on this idea: it’s an evolution of last year’s LineFORM multifunctional snake robot that introduces modularity to the system, letting you tear of a strip of exactly how much robot you need, and then reconfigure it to do all kinds of things. Cont'd...
The ST Robotics Workspace Sentry robot and area safety system are based on a small module that sends an infrared beam across the workspace. If the user puts his hand (or any other object) in the workspace, the robot stops using programmable emergency deceleration. Each module has three beams at different angles and the distance a beam reaches is adjustable. Two or more modules can be daisy chained to watch a wider area. "A robot that is tuned to stop on impact may not be safe. Robots where the trip torque can be set at low thresholds are too slow for any practical industrial application. The best system is where the work area has proximity detectors so the robot stops before impact and that is the approach ST Robotics has taken," states President and CEO of ST Robotics David Sands.