AX-18F

[billyzelsnack]

After updating RoboPlus I noticed something interesting in the Dynamixel Wizard. In the "About Dynamixel Firmware" dropdown it shows in the "Support Dynamixel" list an AX-18F! The picture makes it look like it is the same form-factor as the AX-12. Could this be an 18 volt version of the AX-12? If so.. That would really be fantastic news.

[JonHylands]

After updating RoboPlus I noticed something interesting in the Dynamixel Wizard. In the "About Dynamixel Firmware" dropdown it shows in the "Support Dynamixel" list an AX-18F! The picture makes it look like it is the same form-factor as the AX-12. Could this be an 18 volt version of the AX-12? If so.. That would really be fantastic news.

I would doubt very highly that's what it means - all Dynamixel servos are numbered by the amount of torque the servo has, not the voltage it uses.

- Jon

[BillB]

A beefed up AX servo would be great - particilarly if it had the same shape profile as the AX12 & had metal gears to cope with the extra Torque.

[billyzelsnack]

I would doubt very highly that's what it means - all Dynamixel servos are numbered by the amount of torque the servo has, not the voltage it uses.

Good to know. I did not know that about the naming convention. Wonder why they chose the "torque" at the minimum voltage for the AX-12.

Any idea what the AX vs DX vs RX vs EX means?

[billyzelsnack]

Specs posted:

http://support.robotis.com/en/product/d ... ax-18f.htm

Weight : 54.5g
Dimenson : 32mm * 50.1mm * 40mm
Resolution : 0.29°
Gear Reduction Ratio : 254 : 1
Stall Torque : 18kgf.cm(at 12.0V, 2.2A)
Running Degree§ 0° ~ 300°§ Endless Turn
Running Temperature : -5℃ ~ +85℃
Voltage : 9 ~ 12V (Recommanded Voltage 11.1V)
Max Current : 900mA
Command Signal : Digital Packet
Protocol Type : Half duplex Asynchronous Serial Communication (8bit,1stop,No Parity)
Link (Physical) : TTL Level Multi Drop (daisy chain type Connector)
ID : 254 ID (0~253)
Communication Speed : 7343bps ~ 1 Mbps
Feedback : Position, Temperature, Load, Input Voltage, etc.
Material : Engineering Plastic

I am wondering if they just put in a new motor with slightly more oompf.

On the AX-12+ page they say "Stall Torque : 15kgf.cm(at 12.0V, 1.4A)." That is at the upward of what the AX-12+ can handle so I'd gather that the AX-18F is using a new naming convention using the max torque instead of the old min torque way. If true that'd be unfortunate because I was hoping for more than just 3 extra usuable kgf.cm of torque.

Saying that.. I'm definitely interested. The AX-12's always seemed to be just a tiny bit under torque. That extra 3kgf.cm could make a world of difference. I wonder what the price will be.

[i-Bot]

The latest Dynamixel brochure gives other differences between AX-12+ and AX-18F.

AX-12+ has cored motor, AX18F has coreless motor.
AX-12+ no load speed is 59RPM, AX-18F is 97RPM

Maybe Pedro can put up a scan of the brochure ? It shows the Rx24F specs too.

[billyzelsnack]

That's makes it more interesting. A .103 second / 60 degree servo speed is quite fast. They had enough room to up the gear ratio a little, but they left it alone. I'd guess that the plastic gears are at their max or this is to make manufacturing easier by sticking with AX-12 guts.

Maybe it's reasonably possible to find a replacement motor and mod an AX-12. Though I'd like to open up an AX-18F first and see if they beefed up anything else besides the motor.

[RobotNV]

I compared this:
http://support.robotis.com/en/product/d ... ax-18f.htm
with this:
http://support.robotis.com/en/product/d ... tuator.htm

And these are the only differences:

AX-18FShow
Home > Product Information > Dynamixel > AX Series > AX-18F
ROBOTIS Tech Support v1.00.02AX-18F
Last updated 2010.03.03 (v1.01 Eng)
[AX-18F]
H/W SpecificationWeight : 54.5g
Stall Torque : 18kgf.cm(at 12.0V, 2.2A)
M0 (0X00)Model Number(L)Lowest byte of model numberR18(0X12)
Basic-offered frames with AX-18F are as follows.
F is applied as below. F3 can be connected to 3 sides of AX-18F: Left, Right,