Overview
The AR-3606HB is a standard-sized servo that has been built by Power HD specifically for continuous rotation. At 6 V, it has a maximum rotation speed of 71 RPM (no-load) and can produce up to 93 oz-in (6.7 kg-cm) of torque. It features two ball bearings on the output shaft for reduced friction, and it offers easy access to the rest-point adjustment potentiometer. The servo can be controlled using a direct connection to a single microcontroller I/O line without any additional electronics, which makes it a great actuator for beginner robotics projects.
The AR-3606HB continuous rotation servo converts standard RC servo position pulses into continuous rotation speed. The default rest point is 1.5 ms, but this can be adjusted by using a small screwdriver to turn the middle-point positioner. Pulse widths above the rest point result in counterclockwise rotation, with speed increasing as the pulse width increases; pulse widths below the rest point result in clockwise rotation, with speed increasing as the pulse width decreases.
The servo has a 12″ (300 mm) lead that is terminated with a JR-style connector and includes additional servo horns and mounting hardware. The following picture shows an example of the hardware that might be included (actual hardware could vary):
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This robotics servo, which also sometimes goes by the Power HD part number AR3606HB, is compatible with our servo controllers and has a Futaba-compatible output shaft, which means it works with our servo wheels and sprockets. If you are looking for a similar servo that is capable of limited-range position control as opposed to continuous rotation speed control, consider the Power HD standard servo 6001HB, which has almost the same size, weight, speed, and torque as the AR-3606HB.
Note that, as with most hobby servos, stalling or back-driving this servo can damage it.
Continuous rotation servo comparison
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Continuous rotation servo size comparison. From left to right: SpringRC SM-S4303R, Power HD AR-3606HB, FEETECH FS5106R, Parallax Feedback 360°, Parallax (Futaba S148), and FEETECH FS90R. |
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| 6 V | 4.8 V | Weight (g) | Size (mm) | Digital? | Feedback? | Price | |||
|---|---|---|---|---|---|---|---|---|---|
| Max speed (RPM) |
Stall torque (oz·in) |
Max speed (RPM) |
Stall torque (oz·in) |
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| SpringRC SM-S4303R | 54 | 71 | 43 | 46 | 41 | 41.3 × 20.7 × 40.2 | $12.95 | ||
| PowerHD AR-3606HB | 71 | 93 | 62 | 83 | 40 | 40.5 × 20.0 × 38.0 | $14.95 | ||
| FEETECH FS5106R | 95 | 83 | 78 | 70 | 39 | 40.8 × 20.1 × 38.0 | $13.95 | ||
| Parallax Feedback 360° | 140 | 35 | – | – | 41 | 40.0 × 20.0 × 37.2 |  |
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$27.99 |
| Parallax (Futaba S148) | 50 | 38 | 40 | 30 | 43 | 40.5 × 20.0 × 36.1 | $13.95 | ||
| FEETECH FT90R | 170 | 21 | 135 | 18 | 9 | 22.9 × 12.1 × 26.5 | |
$7.95 | |
| FEETECH FS90R | 130 | 21 | 100 | 18 | 9 | 23.2 × 12.5 × 22.0 | $4.95 | ||
