The Unitree A1 has a maximum payload rating of 5kg.
Although Unitree A1 has a variety of connectors available on top for third party add-ons, by default it does not have many easily available threaded holes for mounting custom payloads.
The image below shows the dimensions of a small mounting plate which has been added to the dog to allow small custom payloads to be added easier. Ideally, payloads should be kept within the 62mm x 100mm region due to clearance requirements for the legs and nearby ports. There are 8 mounting holes, each 6mm deep M3 threads.
There are three female XT30 connectors nearby for providing power to custom payloads. The maximum current output for these is unknown.
Below is an example payload - an Intel Realsense camera mounted to the back of the dog. In this case, not particularly useful as the dog already has a D435i on the front, but it could easily be replaced with something else (e.g. a tracking camera, LIDAR, or other sensors for measuring things like air quality).
