Full specification
| Parameter | Value |
|---|---|
| Frame | Φ90 × 70 mm |
| Ratio | 20:1 · planetary |
| Rated torque | 50 N·m |
| Peak torque | 176 N·m |
| Weight | 1,392 g |
| Supply | 24 V nominal · 24–48 V supported |
| Encoder | Dual encoder (2EC) · single-turn absolute on the output side |
| Comms | CAN / CAN FD |
| Brake | None |
| Torque sensor | None |
Source: DAMIAO 2026 product selection catalogue, DM-J planetary series. Figures verified November 2026 — confirm the exact variant against the datasheet issued with your order.
When this is the right choice
- 176 N·m peak — the highest in the DM-J range short of the 10422, in a 1.4 kg package.
- Knee and hip on a light biped or a quadruped. Planetary shock tolerance is an advantage in a leg.
- 20:1 holds a static load without a brake in most geometries, because the reduction is high enough to resist backdriving.
- Same CAN tooling as the small frames, so one controller runs the whole robot.
When it is the wrong choice
- Precision wrist work. Backlash rules it out of a hand or a fine wrist.
- Force-controlled contact. No torque sensor at any DM-J frame.
- Absolute power-off safety. No brake — backdriving resistance is not the same as a brake.
Alternatives at a similar level
- DAMIAO DM-J10422P — 100 N·m rated, 400 N·m peak at 2,700 g — the top frame
- DAMIAO DM-J6248P — 30 N·m at 660 g for lighter legs
- Tongchuan TCHL-32 — 169 N·m at 3.30 kg with brake and sensor options
- Crabnova CE-RBV3-R120-161 — 180–450 N·m with brake and 500 N·m sensor, 4.10 kg
Quote this model
Model, quantity and destination is enough to start — we come back with price, availability and the datasheet.
DM-J8520 FAQ
Can a 20:1 planetary hold a knee without a brake?
It resists backdriving far better than a 9:1, but resistance is not a brake and it is not a safety device. If the axis must hold with power off, specify a brake separately.
Is 176 N·m peak usable?
For impact and acceleration yes; it is a burst figure. Continuous is 50 N·m, and the thermal time constant is what governs a repeated cycle.
Why not a harmonic at this torque?
Cost and shock tolerance, mostly. A harmonic gives better precision and holding; a planetary gives better impact behaviour and a lower price at the same torque.
How long does it take to ship?
Confirmed per order at quotation.
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