Overview

Ohmni is designed to be modular and extensible. Removing the lid/cover of Ohmni's base reveals most of the electronics.

Base electronics

The board at the rear is called the Core Board and is mainly responsible for lithium battery management, charging and balancing, power control and distribution. It also drives the LED lights at the base and provides a 5V 3A output which powers the main processor board.

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The board slightly below and in front of the Core board is the x86 embedded system at the heart of Ohmni. It is an UP board manufactured by our partner, Aaeon. The main CPU is an Intel Atom x5-Z8350 64-bit Quad Core processor that runs up to 1.92 GHz via Turbo Burst. The driver stack is as follows:

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There are other distributions for the UP board besides OhmniLabs custom Android distribution. If you don't need our software, video conferencing, and telepresence stack, you can potentially reflash the board with Ubuntu or other OSes to run whatever system you like. Please note, however, that doing so will void your warranty.

The UP board is connected via USB to our dual-band 802.11ac USB dongle. It's also connected to the speakerphone in the middle of tube, as well as via USB and HDMI to an expansion hub at the top of the robot and to the touchscreen.

The UP board has extra USB ports that can be used to add other peripherals (sensors, etc.). Be careful about adding very high power peripherals, as they can cause the system to be unstable under heavy load.

For example: Bluetooth BLE USB Dongle could be plugged directly into the USB port of the UP board to extend the connectivity of the bot. Once connected, you just need to restart the bot, then check the Setting to enable Bluetooth and pair with additional devices.

Drives

The four ethernet jacks at the front of the Core Board are not actually ethernet. We use the 8 physical ethernet wires and form factor but actually use it as a shielded, high power bus with two pins for multidrop serial.

NEVER HOTPLUG THE ETHERNET PORTS WHEN THE UNIT IS TURNED ON! This can damage the serial bus and devices on it.

Two of the jacks go to the left and right drives (wheels). The third provides power to the upper parts of the robot. The last port is left available for your development use. Again, DO NOT HOT PLUG ANYTHING IN WHEN THE UNIT IS TURNED ON.

Neck/top electronics

Inside the neck of the robot is a 4-port USB hub that connects to the touchscreen and the front and down cameras. It also has a high power 5V 3A converter that powers all of these peripherals.

We also have a servo that controls the pitch of the screen. It is also directly connected to the high power multidrop serial bus.

Touchscreen

The touchscreen is custom built by OhmniLabs. We combine a 10.1" 1280x800 IPS display and a touch panel via our custom display controller board. This enables the touchscreen to talk to the rest of the system via USB and to control various attributes of the display.

It takes USB power and HDMI input. It only supports native resolution, but theoretically you can plug in almost any HDMI device and it should display correctly.

NOTICE

When adding additional HW accessory to the Ohmni robot, please do not change the possition of the existing wiring. The most common mistake is to change the position of the USB cabled of the Serial bus. It is currently hardcode to tty1-2.1, so changing its possition and access will affect the serial bus.