Walker S1 vs Walker S2: UBTECH Upgrade or Stay?

Choose the Walker S2 if you need a robot that keeps working through shifts, because it swaps its own batteries in about three minutes and walks at up to 7.2 km/h. Choose the Walker S1 if you already run it or want the earlier 2024 model with its factory-system links to carts and autonomous vehicles. The S2 is the newer machine by one year, launched in 2025, and adds LiDAR, Wi-Fi 6 and a developer kit. For a new deployment, the S2 is the safer pick.

The Walker S2 walks faster, reaching up to 7.2 km/h (2 m/s) against 3 km/h stable walking and 5 km/h running for the Walker S1. That makes the S2's top walking pace faster than the S1's running pace. On a factory floor this shortens trips between a shelf and a workstation, which adds up over a full shift. The S1 is slower but is built for steady, repeatable walking while carrying totes, which suits short, fixed routes. Pace also affects how often the robot reaches a station on time.

The Walker S2 runs about two hours on a charge and swaps two 48 V hot-swappable battery modules in around three minutes, while the Walker S1 only lists fast charging with no runtime figure. UBTECH says the S2 can pick swap or charging by task priority, so it can work around the clock. A full recharge takes 90 minutes if you prefer to plug in. The S1 has no swap system, so each charge means a pause. For a plant with two or three shifts, that gap decides how many hours of work you actually get.

Both robots are rated at 15 kg, so neither lifts more than the other. The Walker S1 carries 15 kg continuously and lifts a standard tote of 16.3 kg. The Walker S2 handles 15 kg with its waist and arms inside a workspace that reaches from the floor up to 1.8 metres, and its waist turns up to 162 degrees. The real difference is reach: the S2 is designed to bend to the ground and extend high, which suits shelves and bins.

The Walker S2 adds LiDAR and ultrasonic ranging to its cameras, while the Walker S1 navigates with cameras and a two-stage semantic visual mapping system. The S1 carries two RGB-D cameras, two stereo cameras, fisheye cameras and force sensors in both wrists. The S2 uses dual binocular cameras, depth LiDAR and motion sensors in the torso and feet. LiDAR measures distance with laser light and works in poor lighting, so the S2 copes better with changing factory conditions. The S1 reads objects and rooms well, but it lists no laser-based ranging.

The Walker S2 is easier to connect, with Wi-Fi 6, Bluetooth 5.2, optional 5G, Ethernet and a REST interface plus a Python and C++ developer kit, while the Walker S1 lists Gigabit Ethernet and USB 3.0 only. The S1 runs UBTECH's ROSA 2.0 framework with large-language-model task planning and links with factory management systems and autonomous carts. The S2 runs a real-time Linux system with BrainNet 2.0 and Co-Agent software, plus a web dashboard, so teams can write their own tasks.

The Walker S2 lists more safety features, with emergency-stop buttons on the front and back, soft-skin covers and proximity sensors that detect people nearby. The Walker S1 lists one emergency-stop button, force sensing in the wrists and ankles, and touch sensing in the hands. Both belong in a fenced industrial area. The S2's soft covers reduce the harm from light contact, and its proximity sensing helps it stop before a collision, which matters for mixed teams. Check each plant's own safety rules before removing any fence.

Yes, both can be coordinated, but they do it differently. The Walker S1 is described as fully autonomous, with the BrainNet system tying it into factory management, autonomous carts and logistics vehicles. The Walker S2 supports multi-robot coordination and swarm task execution, runs fully on its own, and falls back to remote supervision through a secure web interface. Fleet operators will find the S2's dashboard and remote option easier to manage across many robots. Smaller sites with one or two robots may not notice the difference.