RoboSavvy Forum

How to interface with DX 117 using USB-2-Dynamixel adapter

2007-10-14T13:12:17+01:00

The RX-64 normally runs on 18 volts, and the control table says 24 volts is the absolute max, so that's okay. The DX-117 control table says the high limit voltage is 19 volts, so it should be okay as well.

- Jon

Statistics: Posted by JonHylands — Sun Oct 14, 2007 1:12 pm

How to interface with DX 117 using USB-2-Dynamixel adapter

2007-10-14T02:18:21+01:00

Careful.. Two 2cell lipos in series will be 16.8V when fully charged.

Statistics: Posted by billyzelsnack — Sun Oct 14, 2007 2:18 am

How to interface with DX 117 using USB-2-Dynamixel adapter

2007-10-13T13:51:16+01:00

Ok, I´ll try to answer those questions to the best of my knowledge, I´m more at home at the software side of things, so bear with me
We´re using 2 LiPo Packs in the feet, each having 7.4V/1300 mAh. Together those provide 14.8V to the servos. They´re also supplying power to a custom built power management PCB which in turn powers the PC104 board in the back (Geode LX 500Mhz) and the microcontroller, which is no CM-2, but has a Renesas SH2 processor.

You might also want to look at the Team Description Paper for RoboCup 2007, if you haven´t already:
http://www.sim.tu-darmstadt.de/publ/dow ... dp-hum.pdf
Note that some data there is outdated though. There used to be 3 LiPos on the robot for example, this was changed to 2 as described above.

/edit: Not sure about max and average current draw right now, gotta ask those in the know sometime later.

Statistics: Posted by SK — Sat Oct 13, 2007 1:51 pm

How to interface with DX 117 using USB-2-Dynamixel adapter

2007-10-13T10:15:57+01:00

Hi SK

just a quick question what do you use for a power source and what's your power management dealt with. I'm in the process of designing a power management PCB to regulate a 6 cell lipo down to 15V. What sort of current does you bot draw. Also are you still using the CM2 or have you moved on to another type of controller. If your interested I use a gumstix.

bren

Statistics: Posted by Robo1 — Sat Oct 13, 2007 10:15 am

How to interface with DX 117 using USB-2-Dynamixel adapter

2007-10-13T09:27:55+01:00

NovaOne wrote:
SK, How "intelligent" (autonomous) is your HR18 when playing soccer?

The robot is completely autonomous when playing soccer. The only signals it might receive from "outside" are gamestate signals (e.g. mainly "kick off"). The robots are allowed communicate with each other over WLAN though, ours use this to negotiate their roles (striker, goalie, defender) and exchange information about ball, own position etc.

Statistics: Posted by SK — Sat Oct 13, 2007 9:27 am

How to interface with DX 117 using USB-2-Dynamixel adapter

2007-10-13T10:38:03+01:00

Thanks for the replies guys.

Rocky:

I wish I had more free time to get into the whole humanoid stuff.

I know what you mean, thats why i bought a ready designed kit robot.

SK, How "intelligent" (autonomous) is your HR18 when playing soccer?

Bren, no one stands a chance against you at ROBOtic'07

Chris

Statistics: Posted by NovaOne — Fri Oct 12, 2007 8:13 pm

How to interface with DX 117 using USB-2-Dynamixel adapter

2007-10-12T16:01:16+01:00

I'm not using my DX-117s for Bioloids. I am actually using them as plain old servos that control fins in an underwater vehicle.

I wish I had more free time to get into the whole humanoid stuff.

Rocky.

Statistics: Posted by Rocky — Fri Oct 12, 2007 4:01 pm

How to interface with DX 117 using USB-2-Dynamixel adapter

2007-10-12T16:42:29+01:00

NovaOne wrote:
HR18 was made my the Hajime Team for Robocup, SK is a Hajime team member [*] and a Robosavvy member.

Indeed
We´re using RX-64 for both knees and for the waist (allowing bowing motion). At first, we used DX-117s only, but experience showed that those were a little overwhelmed (mainly overheating) with the task in those locations.
RX-64s are heavy, expensive and a little slower than DX-117s though, so it depends on application and robot design (and wallet ) if they´re a good choice or not.
Also don´t forget about the relatively new RX-28, which is in the DX-117s size/power class (a bit bigger) and marketed to feature some improvements over the DX-117 by Robotis. Don´t know how the prices compare though.

/edit: [*] Slight correction: I´m member of the Darmstadt Dribblers, we use the HR18 robot made by the Hajime Research Institute. Unlike 2006, we didn´t attend RoboCup 2007 as the joint Darmstadt Dribblers & Hajime team. There are still close ties with Hajime Research Institute though.

Statistics: Posted by SK — Fri Oct 12, 2007 1:09 pm

How to interface with DX 117 using USB-2-Dynamixel adapter

2007-10-11T10:00:31+01:00

I use D-117 through out my biped.

I had a look at the RX-64's but the weight to torque was to high e.g. there very strong but weigh in at 106g that would be over 2.2Kg just in servos!

Bren

Statistics: Posted by Robo1 — Thu Oct 11, 2007 10:00 am

How to interface with DX 117 using USB-2-Dynamixel adapter

2007-10-10T20:57:16+01:00

Amazing!
I just found HR18 which uses three RX-64's

HR18 was made my the Hajime Team for Robocup, SK is a Hajime team member and a Robosavvy member.

But what you guys (Rocky, Bren Dewey.......) using them for, on your Bioloids ?

Chris

Statistics: Posted by NovaOne — Wed Oct 10, 2007 8:57 pm

How to interface with DX 117 using USB-2-Dynamixel adapter

2007-10-10T19:34:36+01:00

If you think the DX-117 looks good, spend a little bit more money and get an RX-64. 64 kg-cm of torque (800+ oz-in).

- Jon

Statistics: Posted by JonHylands — Wed Oct 10, 2007 7:34 pm

How to interface with DX 117 using USB-2-Dynamixel adapter

2007-10-10T19:18:09+01:00

The DX117 looks like an awesome servo!

Can I ask what joints you guys are using it for?

At £99, a bot using totally dx117 would be surely be unstoppable.

Chris

Statistics: Posted by NovaOne — Wed Oct 10, 2007 7:18 pm

How to interface with DX 117 using USB-2-Dynamixel adapter

2007-10-10T00:16:12+01:00

Hey Bren,

Thanks for all that info. I appreciate it.

I used LabView on Windows to program the actuators. LabView is a graphical programming tool produced by National Instruments. LabView is primarily an engineer's tool. Since my project was more engineering and less computer science oriented, I chose that path. I used the actuators to control the fin angles of a wind tunnel test model of a UUV(Unmanned Underwater Vehicle). This allowed me to change fin angles remotely, without shutting down the wind tunnel fan and changing the angles manually which is a very expensive and time consuming process. Furthermore, it is much easier to code up something with a fancy operator's GUI in LabView. So the code will all be graphical and you will need LabView and the USB2Dynamixel adapter to connect to the DX-117s.

Rocky

Statistics: Posted by Rocky — Wed Oct 10, 2007 12:16 am

How to interface with DX 117 using USB-2-Dynamixel adapter

2007-10-09T11:27:23+01:00

Hi

I got the gumstix working using SPI only through bit banging. I tried using the SPI that's built in but after speeding a couple of hours on it gave up and used JonHylands example bit bang program and had it working in a couple of hours. I also had to bit bang the arduino side as there's no example of atmel chips in slave mode, they give you two lines of code for the receive and the reg configuration but had no joy getting them to work.

I find the gumstix really good. The only down side is the doc's if you go for a older boards there's plenty but I've got the new verdex board so none of the example code works as there different chips. This is the only problems I've found but a very annoying one as you have to take the example code and try and modify it to work. Got the GPIO ports working so at leased I can bit bang.

What did you implement you code on XP or linux did you use a max485 chip (I've just ordered one). Would love to look at some of your code.

What's the project.

Bren

Statistics: Posted by Robo1 — Tue Oct 09, 2007 11:27 am

I used LabView to finally get my servos to work.

2007-10-09T05:32:51+01:00

I have to say that it was quite easy to code once I understood how to construct and decode packets.

if you have any questions, please don't hesitate..

On another note, can you give me some info about the SPI interface you seem to have used? I'm in the process of acquiring a sensor with the SPI interface and am trying to decide between a Gumstix board or a Microcontroller. Any help would be greatly appreciated.

Statistics: Posted by Rocky — Tue Oct 09, 2007 5:32 am