Mounts

UMi 17X harmonic drive telescope mount from Proxisky

Tuesday, November 4, 2025

Built for precision astrophotography, the UMi 17X harmonic drive telescope mount from Proxisky introduces the new servo SWG system, combining advanced dual-mode operation, carbon fiber construction, and servo-driven strain wave gear mechanics.

Proxisky has introduced the UMi 17X, a compact German equatorial and Alt Az telescope mount designed for astrophotographers who value both precision and portability. It is built for those long nights under the stars when every arcsecond of tracking matters just as much as every pound of gear you carry.

The UMi 17X has a servo driven strain wave gear system, the same type of drive often found in robotics. This design allows for highly accurate motion control while keeping the mount light enough to take anywhere. It is the kind of thoughtful engineering that focuses on function and reliability.

The hybrid configuration supports both German equatorial and Alt Az orientations, giving it the flexibility to handle deep sky imaging or casual visual observing. Whether you are aligning on Polaris for long exposures or sweeping the horizon for faint nebulae, the mount adapts naturally to your setup.

Above photo credit: Proxima Build Smart Technology (Hong Kong) Co., Ltd.

Structural engineering and materials

Weighing just 4.3 kg, the UMi 17X is one of the lightest servo SWG mounts in its class. Its design integrates carbon fiber and aerospace-grade aluminum to provide rigidity without adding unnecessary bulk. The mount’s wedge design is backlash-free, self-locking, and stop-less, allowing precise alignment adjustments even under load.

The base connection system supports both 3/8" and 6×M6 mounts, with native compatibility for CF40 and TC40 tripods - enhancing setup flexibility for field imaging. Every joint and fastener has been optimized for repeatability, contributing to the mount’s long-term durability and pointing consistency.

Advanced drive and gearing system

The UMi 17X employs servo motors on both axes — a type-17 SWG direct-drive system on the RA axis and a type-14 SWG direct-drive system on the Dec axis. This dual configuration ensures high torque and smooth motion while minimizing backlash, a key factor for long-exposure astrophotography.

Payload capacity: 12 kg without counterweight, up to 18 kg with counterweight
Periodic error (PE): ±10 arc-seconds (factory tested, PE report included)
GOTO speed: 3.5°/s nominal, 7°/s maximum
RA limit: Physical limit sensor (software adjustable)
Power-loss braking: RA electromagnetic braking system (>48 N-m torque)
Anti-collision system: Dual-axis protection

This engineering balance gives users precise slewing and tracking while protecting against over-travel or accidental impact during automated movements.

Photo credit: Proxima Build Smart Technology (Hong Kong) Co., Ltd.

Tracking precision and automation

The integrated OnStepX operating system powers the mount’s internal controls, allowing for smooth tracking adjustments, accurate GoTo positioning, and compatibility with popular third-party software including ASIAIR, NINA, and KStars.

The periodic error performance of ±10 arc-seconds ensures minimal star trailing even in long unguided exposures, while its servo feedback loop continuously refines motor positioning in real time. Proxisky’s inclusion of a physical home sensor and FRAM secondary Dec sensor provides reliable synchronization between sessions and allows users to resume imaging after interruptions without manual recalibration.

The mount also supports an electronic polar scope with native integration for iPolar and PoleMaster, eliminating the need for separate alignment adapters.

Connectivity and power management

The UMi 17X offers modern connectivity options that rival professional observatory mounts. It includes:

USB Type-C ports (for mount and ST4 guiding)
Wi-Fi and Bluetooth connectivity
Control via UMi Mount App
DC power output: Up to 10 A at 12 V for cameras and accessories

The mount accepts a 12-24 V DC input (5.5×2.1 mm connector), offering flexibility for field battery packs or observatory power supplies. Efficient power management keeps current draw minimal while still supporting high-torque slews.

Mechanical specifications overview

Specification	Detail
Item	UMi 17X
Mount Type	GEM, Alt-Az (0-90° supported)
Weight	4.3 kg
Materials	Carbon Fiber, 6061 Aluminum, 304 Stainless Steel
Finish	Anodized with rust-proof coating
OS	OnStepX
Supported Software	ASIAIR, NINA, KStars, and more
RA Drive	Servo motor, Type-17 SWG, Direct Drive
Dec Drive	Servo motor, Type-14 SWG, Direct Drive
Payload	12 kg (no CW) / 18 kg (with CW)
Periodic Error	±10 arc-sec (PE test report included)
Home Position	Physical home sensors + FRAM secondary Dec sensor
RA Limit	Physical limit sensor (software adjustable)
Saddle	Vixen-Losmandy dual type
CW Shaft Thread	M12
Power Input	12-24 V DC, 5.5x2.1 mm
Wedge Design	Backlash-free, self-locking, stop-less
Base Connection	3/8", 6xM6, CF40/TC40 compatible
Interface	USB-C, Wi-Fi, Bluetooth, ST4
Saddle Connection	USB-C, DC power output up to 10 A at 12 V
GOTO Speed	3.5°/s normal, 7°/s max
Power-loss Braking	RA electromagnetic, >48 N-m
Anti-Collision	Dual-axis system
Electronic Polar Scope	iPolar & PoleMaster native support
Price	$2,299 USD

Field application and user experience

In field use, the UMi 17X’s combination of portability and tracking precision places it between lightweight travel mounts and heavier observatory mounts. The hybrid GEM/Alt-Az design gives flexibility for both imaging and visual astronomy.

The 18 kg maximum load with counterweight allows pairing with medium-sized refractors or astrographs while keeping vibrations low. The carbon fiber construction absorbs mechanical resonance effectively, reducing tracking oscillations common in lighter mounts.

The dual-axis anti-collision system is particularly useful for remote or automated operation, protecting equipment in case of misalignment or software errors. This adds a professional-grade safety feature to a consumer-grade system.

UMi 17X harmonic drive telescope mount from Proxisky

The Proxisky UMi 17X demonstrates how modern servo control and strain wave gearing can redefine portable astrophotography mounts. Its integration of advanced materials, servo feedback, and dual-axis protection combines mechanical strength with technological refinement.

At $2,299, it enters the mid-range segment with specifications previously reserved for heavier, more expensive mounts. For astrophotographers seeking compact precision, intelligent control, and robust construction, the UMi 17X sets a new benchmark for portable SWG mount engineering.