Please note that there are several
flavors of HerkuleX and Dynamixel
servo actuators; each series may have
different communications, power, and
programming requirements. I’ve only
noted manuals for the three types of
servos that I have in my junk box.
All of these servos prices start out
at around US$40. As you want
stronger and faster actuators, the
prices go up dramatically. I have
included the wCK modules in this list
for European readers because as far
as I can tell, there are no current US
distributors for these servos.
Servo actuators of this type are
designed to be used in robots — not
model cars and airplanes — so their
connection systems are better tuned
for us. For example, the Dynamixel
actuator has mounting holes all over it
for installing nut/bolt combinations
(see Figure 1).
Not shown in the photo is the
mounting hole on the back of the
actuator that is in-line with the servo
horn on the front. This allows the AX-
12A to be fully supported at the joint
for a strong connection.
The HerkuleX actuator (see
Figure 2) does not have as many
Feature HerkuleX DRS-0101 Dynamixel AX-12A wCK-1111T
Voltage range 7-12V ( 7.4V rec.) 7-12V ( 9.6V rec.) 6-12V ( 9.6V rec.)
12 kg-cm 16. 5 kg-cm 11 kg-cm
Speed2 0.166 sec/60° 0.196 sec/60° 0.15 sec/60°
Communications Full-duplex 8N1 Half-duplex 8N1 Full-duplex 8N1
Comm. Speed max 667 Kbps 1 Mbps 921 Kbps
Set transit speed Yes Yes Yes
Set transit time Yes No No
Set torque Yes Yes Yes
Set LED Yes (four LEDs) Yes (one multi-color) Yes (two colors)
Set temperature Yes Yes No
Report position Yes Yes Yes
Report loading No Yes Yes
1. Stall torque at recommended voltage.
2. Speed at recommended voltage.
Table 1. Features of interest.
Your robotic problems solved here.
SERVO 10.2013 11