Born from large professional installations, now available for custom and advanced observatories worldwide
The Caterpillar automates and safeguards dome rotation and roof operations in professional and custom-built observatories. Based on the Beaver platform, the same hardware trusted by NexDome and thousands of installations globally.
Caterpillar is a precision motion controller, not an all-in-one observatory brain. Understanding its role helps you plan the right system architecture.
All variants support external safety and weather sensor inputs, and all can self-calibrate for optimal positioning accuracy.
The full dome controller, with separate boards for rotation and shutter, auto-connected via WiFi. Supports a wide range of motor types — 3-phase, DC and stepper (always with external drivers) — plus encoders and limit/home switches.
Relay-based model designed to retrofit existing observatories originally operated with manual buttons. Automates opening, closing and rotation through relays, while maintaining precise encoder-based positioning.
Answer two questions. We'll show you the right controller, the hardware you'll need, and direct links to the relevant documentation.
Drives your rotation motor directly and — through a separate wireless shutter unit — controls the dome opening. Handles encoder-based azimuth positioning, home sensing, and safety interlocks in one integrated system.
Connects to your existing button-operated drive through relays — no rewiring of the motor system itself. Adds full software control, encoder positioning, and home sensing on top of whatever mechanical setup you already have running.
Both Caterpillar roof controllers offer ASCOM and INDI support and run standalone over USB or WiFi, or alongside Dragonfly or Starling.
Dedicated stepper-motor roll-off controller. Drives motors up to 2.7 A directly, with precise step positioning and limit switch support.
Planned variant for DC and AC motor drives. If your roof uses a motor we don't yet support, reach out — we develop these to order in a realistic timeframe.
Caterpillar works as one layer of a well-designed observatory control system — responsible for motion, while other systems handle weather and coordination.
Caterpillar manages motors, reads encoders and limit switches, and executes safe open/close/rotation sequences. It is the layer closest to the mechanics.
Weather and sky safety are provided by external systems whose inputs Caterpillar accepts to enable automated, safe operation.
The Caterpillar ASCOM driver integrates with ASCOM Device Hub and any ASCOM-compatible automation software — USB or Wi-Fi connection, full configuration and real-time control.
| Connectivity | USB + WiFi |
| Motor types (Full) | 3-phase, DC, Stepper (with external drivers) |
| Motor types (SSR) | Stepper only |
| Motor types (CaterpillarR) | Any (relay-based control) |
| Positioning | Encoder-based feedback |
| Limit switches | Supported on all variants |
| Home sensor | Supported (dome rotation re-sync) |
| External inputs | Safety and weather sensors |
| Manual controls | Push buttons for CW/CCW, open/close, calibration |
| ASCOM drivers | Dome + switch |
| INDI / INDIGO | Available |
| Self-calibration | Rotation, shutter and roof |
| Platform | Based on Beaver (used by NexDome) |
Windows software available for tuning external motors (full controller variant). Firmware updatable by the user.
Free shipping to most countries on direct orders. · Dealers worldwide →
Overview covering all Caterpillar variants — architecture, wiring and integration.
Read manual →Specific guide for the relay-based retrofit variant.
Read manual →Specific guide for the roll-off roof stepper motor variant.
Read manual →Latest firmware for CaterpillarR and SSR, plus the ASCOM driver for all variants.
Go to downloads →Downloadable STL files for enclosures, adapters and mounting brackets for the Caterpillar system.
