Mitsubishi Electric

The general public knows Mitsubishi as a car manufacturer but like many Japanese car manufacturers they have other branches in the industrial sector and Mitsubishi Electric is one of them.  Their line of controllers are called MELSEC series.  As of this writing these 7 listed below are their staple series but they do produce a few application specific PLCs like for robots:

• MELSEC iQ-R - Med-Large Scale: "A next-generation programmable automation controller (PAC), the    MELSEC iQ-R Series incorporates a revolutionary high-speed system bus that improves productivity through advanced performance and functionality."
• MELSEC iQ-F - Small/Stand alone: "Designed to provide outstanding performance and superior drive control, the MELSEC iQ-F Series is a high-performance compact-class controller with a rich assortment of integrated functions."
• MELSEC Q - Med-Large Scale: "The first to incorporate the multiple CPU architecture, the MELSEC-Q Series wide-range of CPUs enables control of multiple operations, improving the performance and scalability of the overall production system."
• MELSEC L - Small to Med Scale: "The MELSEC-L Series is a baseless highly scalable controller ideal for applications having limited space. With various I/O functionality embedded into the CPU head, exceptional cost versus performance is achieved in a compact body."
• MELSEC F - Small/Stand alone: "Incorporating abundant features with a flexible system configuration, the MELSEC-F Series has a power supply, CPU and I/Os into a single compact body. Furthermore, a diverse range of options are available to further expand its capabilities."
• MELSEC QS/WS
• MELSEC A

Here is a line from Mitsubishi themselves:

"Mitsubishi Electric’s controller line is one of the widest in the industry. Our offering spans from our Alpha Simple Application Controller with as little as six I/O points, all the way to the high-end Q Series Automation Platform capable of running entire plants with thousands of I/O. Our controllers are complemented by a comprehensive array of software tools and networking technologies. Offering seamless integration to our other automation products such as VFDs, motion control and HMIs, to provide a comprehensive solution with the controller at the center." 

Here is the link to their Application Selection Guide.  As with everything else in life, mileage may vary so you will have to do some research to decide which PLC is right for your application.