Electrical

Asimov 1 battery, power, control electronics, actuator communications, sensors, and media hardware.

Overall Architecture

Subsystem	Role
RPU (Radxa CM5 and custom carrier board)	Runs locomotion, motor control, IMU feedback, battery management, and actuator CAN communications
Raspberry Pi 5	Connects camera, microphone, speaker, networking, and edge services
Actuator network	Carries battery power and CAN communication through the robot
Sensors and media	Provide inertial state, video, audio input, and audio output
Battery system	Supplies energy for actuators, compute, sensing, and peripherals

The RPU combines a Radxa CM5 compute module with a custom carrier board designed specifically for robot control. It handles high-frequency, low-latency workloads that need close-to-metal performance, including running the locomotion policy, controlling the motors, reading IMU telemetry for the policy feedback loop, monitoring the battery-management system, and maintaining the low-level robot state.

The custom carrier board is also responsible for communication with all 25 actuators. Its CAN interfaces send motor commands and receive joint position, velocity, current, temperature, and fault data from the distributed actuator network.

The RPU and Raspberry Pi 5 communicate over a direct Ethernet connection. Keeping media, external networking, and application services on the Raspberry Pi prevents those workloads from interfering with the RPU's time-sensitive control loop.

Actuator Power and Communication

The published system specification identifies five CAN interfaces at 1 Mbps and one at 500 kbps. The actuator network distributes battery power and CAN communication from the body outward through six physical branches.

Daisy-Chain Architecture

Each actuator has two electrically equivalent XT30 (2+2) ports. Each port carries BATT+, BATT-, CAN_H, and CAN_L, allowing power and communication to continue from one actuator to the next.

The six branches enter the body at left hip pitch, right hip pitch, waist yaw, left shoulder pitch, right shoulder pitch, and neck yaw. Within each branch, actuators form a chain from the central body toward the distal joint.

For example, each leg follows:

hip pitch -> hip roll -> hip yaw -> knee -> ankle A -> ankle B

This topology keeps the number of body-entry connections small while allowing each limb to carry power and CAN through the same connector system.

Wire-to-motor visualization coming soon

An interactive visualization will be added here to show how every wire connects through the actuator network.

CAN mapping under confirmation

The public sources do not yet reconcile the six physical branch-entry paths with the controller specification of five 1 Mbps CAN interfaces plus one 500 kbps interface. Treat the physical topology and controller-interface count as separate facts until the release-specific bus assignment is confirmed.

Sensors and Media Hardware

Device	Current specification	Primary role
IMU	6-axis	Body orientation and angular-motion sensing
Camera	2 MP monocular camera	Robot video and visual input
Microphone	Stereo microphone array	Audio capture
Speaker	10 W, 4 ohm	Robot audio output

The Raspberry Pi 5 is the currently supported edge computer for camera, audio, networking, and edge services. Other Raspberry Pi models are not validated for Asimov 1.

Battery

The current pack design is a 13-series, 4-parallel lithium-ion battery.

Parameter	Current specification
Battery type	Lithium-ion
Cell model	INR18650
Pack configuration	13S4P
Nominal voltage	46.8 V
Typical capacity	10.5 Ah
Minimum capacity	10.05 Ah
Energy	491.4 Wh
Charge voltage	54.6 V
Discharge cut-off	35.75 V
Standard charge current	2.1 A
Maximum charge current	15 A
Standard discharge current	2.1 A
Maximum discharge current	30 A
Storage voltage	45.5 to 48.1 V
Battery mass	Approximately 2 kg

Operating Temperature

Condition	Temperature range
Charging	0°C to 45°C
Discharging	-20°C to 60°C
Storage, less than 1 month	-10°C to 45°C
Long-term storage, less than 3 months	-10°C to 35°C

Protection Circuit

The pack includes a protection circuit module for over-charge, over-discharge, and over-current protection.

Protection item	Threshold
Over-charge protection	4.25 V per cell
Over-discharge protection	2.75 V per cell
Over-current protection	30 A or less