>[!summary] >Rocket Lab's mid-sized wheel designed for spacecraft classes within 250-600 kg range. The design leverages the same principles and high reliability parts with flight heritage in our other > 🔗 Official Page: https://www.rocketlabusa.com/space-systems/satellite-components/reaction-wheels 📋 Data Sheet: [[RW4-5.0-Datasheet-v2.pdf]] ![[Pasted image 20250108213607.png]] ## Specs | Parameter | Value | | ------------------------------ | --------------------------------------------------------------------------------------------------------------------------------------------- | | Momentum (Nominal) | ±5.0 Nms | | Torque | ±150 mNm (see torque-box) | | Control Mode | Speed or Torque | | Command/Telemetry | Redundant RS-485 | | Mechanical Dimensions | 194 mm x 192 mm x 57.25 mm | | Mass | 3.0 kg max | | Imbalance (Static) | <3 g·mm (average) | | Imbalance (Dynamic) | <200 g·mm² (average) | | Supply Voltage | 24 V to 34 V (nominal 28 V) | | Supply Power (28 V Vacuum) | 20 W @ 5.0 Nms steady state<br>65 W @ 5.0 Nms +75 mNm torque<br>108 W peak @ 4.4 Nms +150 mNm torque | | Environment (Thermal) | −30° C to +70° C (operating) | | Environment (Vibration) | 14 gRMS | | Environment (Radiation) | 50 kRad TID (bare board), Up to 50 MeV·cm²/mg on most active parts | | Environment (Shock) | 1200g, 1kHz-10kHz | | Heritage (As of March 20 2025) | Mechanical design from 0.06/0.2/0.4/1.0 Nms models; Reinforcements from 12 Nms model; Rad-tolerant electronics from 0.2/0.4/1.0/12 Nms models |