Host Computer

The computer that issues commands and does high-level computing, while a lower-level controller executes them.

“Host computer” (上位机, literally “upper-position computer”) is common engineering shorthand in China's robotics industry for the computer in a robot system that handles high-level decision-making, the user interface, and data processing — usually a PC, industrial PC, or a board like an NVIDIA Jetson. It sends target positions, velocities, and other commands over Ethernet, USB, or CAN bus to the “lower-level controller” (下位机: a microcontroller or motor driver that directly drives motors and reads sensors), and receives status data back. This split lets compute-heavy tasks without hard real-time requirements — vision, planning, running a neural-network policy — run on the host computer, while tight, high-frequency control loops (current loop, position loop) stay on the lower-level controller. In embodied AI work, the VLA model usually runs on the host computer; “host computer software” also often refers to the debugging or GUI program running on this machine.

ExampleA GPU-equipped PC running a policy model that sends target joint positions to a Unitree G1 over Ethernet via the Unitree SDK is acting as the host computer.

Also called

Main Control Computer, Upper Computer

Related

Lower-Level Controller · Industrial PC · Onboard Compute Platform · Robot Controller · Qt · Software Development Kit

Sources

上位机 - 百度百科 (Chinese)