On Facebook I noticed that Robotis was calling for beta testers for their upcoming XL430 servos. I thought that would be interesting and gave them a post and an application form. So after a couple of weeks I got 3 of the new XL430 on my door.
Take a look at this Preliminary Product document for all the available specs. I believe these servos are going to be pretty popular. I'm not sure about the cost (they do say low cost), maybe somewhere between the AX-12 and AX-18?
But compared to the AX-12 and AX-18 the specs are superior.
Some points to mention.
- Contactless absolute encoder (12BIT,360 deg!)
- Smaller formfactor than the AX-12/18, about same torque/speed as the AX-12
- Protocol 2 with all the new features
- TTL Async bus up to 4.5 Mbps
- 4 Different operation modes
- Real PID
- Different velocity profiles
- Secondary shadow ID and much more
A picture of the content of one servo-box:
Very useful that it comes with a cable with the new and the old connector. For testing I connected one servo to the USB2AX and using their R+ manager 2.0. Watch my instagram for short test vids of it moving.
A couple of pics compared to AX-12/18:
When it comes to the mounting holes there are some cons and pros. On the bottom and both sides there are 4 mounting holes that are 4mm deep and a diameter of 2.1mm. On the top and front there are only two holes. But you can use the case screws on the front side too (look at the document). But I'm not sure if I like that the hole isn't metal tapped, only based on selftapping screws. In the long term this isn't a good solution.
I really like the relative narrow depth of the servo. I measured the depth (distance between the front and rear horn) to be about 37.80mm. The manual says 34mm, but that's only the servo case. For a legged robot this is good news.
If you are interested in other dimensions let me know. The horn has a diameter of 20.35mm, the 4 mounting holes on the horn is metal tapped and matches the AX-12/18 pattern.
Their solution for the rear free-horn is simply ingenious. I love that you can guide the wire through the horn and it give a good solution for avoiding to much twist and movement of the wire during movement.
I must say I love the increased resolution and full 360 travel. Especially their extended position control mode (multi turn) that gives you an exact position range of-1,048,575 ~ 1,048,575 !I can imagine letting the servo drive a large gear for more torque on a legged robot.
I'll do some more testing and hope to get time posting more info. Maybe taking one apart?
Btw, I'm wondering if someone has already written a new Protocol 2.0 library? I thought I should give it a try on one of my Teensy's too.
Oh, I'm not sure if you know that the MX servos can be updated to the Protocol 2?