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Crustcrawler Smart Arm AX-12A + CM-700+ roborealm AVM

Bioloid robot kit from Korean company Robotis; CM5 controller block, AX12 servos..
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2 postsPage 1 of 1

Crustcrawler Smart Arm AX-12A + CM-700+ roborealm AVM

Post by adamsya » Tue May 29, 2012 10:00 am

Post by adamsya
Tue May 29, 2012 10:00 am

Hi Robosavvy community,

I have a bit of problem on AX12 dynamixel. I am now using crustcrawler robot arm and roborealm.. I try to make a pan and tilt program for arm robot..


First try I have make a program just to make the robot follow an object on x-axis(horizontal, base servo only).. the program working fine, but the movement of the robot is not smooth..


this is one part of the VB script program..


.
.
.
if dX > threshold and turret_h > -512 then
' The object is at left side
turret_h = turret_h + 1
end if
.
.
if dX < -threshold and turret_h < 511 then
' The object is at right side
turret_h = turret_h - 1
end if
.
.
.
turret_v128 = turret_v + 512


The variable "turret_v128" is sent to servo 1, as a "goal position" value.. the +1 is small value, maybe robot base cannot move precisely because other factor such as load..


The question is, what other variable I must find and sent to dynamixel motor so it can move smoothly? example: CW/CCW compliance slope/margin or moving speed or torque limit?

Roborealm AVM module:
Image

Roborealm dynamixel module
Image

Roborealm VB script module:
Image

Example movement I want:
http://youtu.be/94VqAmtHlFA

My robot movement 1:
http://youtu.be/OlgV-7UE5Us

My robot movement 2:
http://youtu.be/HY4O_8jNz8g
Hi Robosavvy community,

I have a bit of problem on AX12 dynamixel. I am now using crustcrawler robot arm and roborealm.. I try to make a pan and tilt program for arm robot..


First try I have make a program just to make the robot follow an object on x-axis(horizontal, base servo only).. the program working fine, but the movement of the robot is not smooth..


this is one part of the VB script program..


.
.
.
if dX > threshold and turret_h > -512 then
' The object is at left side
turret_h = turret_h + 1
end if
.
.
if dX < -threshold and turret_h < 511 then
' The object is at right side
turret_h = turret_h - 1
end if
.
.
.
turret_v128 = turret_v + 512


The variable "turret_v128" is sent to servo 1, as a "goal position" value.. the +1 is small value, maybe robot base cannot move precisely because other factor such as load..


The question is, what other variable I must find and sent to dynamixel motor so it can move smoothly? example: CW/CCW compliance slope/margin or moving speed or torque limit?

Roborealm AVM module:
Image

Roborealm dynamixel module
Image

Roborealm VB script module:
Image

Example movement I want:
http://youtu.be/94VqAmtHlFA

My robot movement 1:
http://youtu.be/OlgV-7UE5Us

My robot movement 2:
http://youtu.be/HY4O_8jNz8g
adamsya
Robot Builder
Robot Builder
Posts: 7
Joined: Tue May 29, 2012 7:18 am

Post by i-Bot » Tue May 29, 2012 10:46 am

Post by i-Bot
Tue May 29, 2012 10:46 am

The usual approach is not to use the parameters within the AX12 to control the speed and "smoothness" of the motion.
The desired motion distance and transit time, are taken and an appropriate position curve over time mapped between them in software. The curve is split into segments on a time spacing of around 20 millisec per segment, and the positions then sent to the servo on this timeframe.
This software is usually better done in the CM700 so the update speed is not impacted by and slow communication with the computer.
The usual approach is not to use the parameters within the AX12 to control the speed and "smoothness" of the motion.
The desired motion distance and transit time, are taken and an appropriate position curve over time mapped between them in software. The curve is split into segments on a time spacing of around 20 millisec per segment, and the positions then sent to the servo on this timeframe.
This software is usually better done in the CM700 so the update speed is not impacted by and slow communication with the computer.
i-Bot
Savvy Roboteer
Savvy Roboteer
User avatar
Posts: 1142
Joined: Wed May 17, 2006 1:00 am


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