Robotic arm

In the last two years or so, I started learning about 3D printing and coding various microcontrollers. The ultimate purpose is to bring these into STEM education and promote maker culture in schools. Last year in 2019, I started a MakerClubQUT and began documenting various maker projects. End of 2019, I started building my first simple robotic arm and thought about the 3D rotations for the robotic arm to reach any particular location in space. I thought that I might try coding a virtual robotic arm in VRMath2, and here it is.

This virtual robotic arm is in a continuous animation, and could be easily modified with some sliders to control the 4 rotations in it. To achieve the movement, I used cascading TRANSFORMs and apply simple SPIN or ORIENT for the arm to move. Below are the codes to create this virtual robotic arm in VRMath2 Editor. 

; Robotic arm
; By Andy (2020)
CS RESET
TRANSFORM
MAKE "roboarm OBJECT
SETPARENT :roboarm
SETSCALE 1 .5 1
CYLINDER
SELECT OBJECT
SETIT 3 26
DESELECT
UP 0.3
; upper arm
SETMAT 0 25
SETSCALE 1 1 1
TRANSFORM
MAKE "upperarm OBJECT
SETPARENT :upperarm
; preparing upperarm movement
COLLECTORI "upperarm_movement
RD 60 RU 60 RU 60 RD 60
ENDCOLLECT "upperarm_movement
SETSCALE .5 .5 .5
BALL
UP 0.5 EAST .15
SETSCALE .1 1 .2
BOX
WEST .3
BOX
EAST .15
UP 0.5
; lower arm
SETMAT 0 21
SETSCALE 1 1 1
TRANSFORM
MAKE "lowerarm OBJECT
SETPARENT :lowerarm
; preparing lowerarm movement
COLLECTORI "lowerarm_movement
RD 120 RU 120 RU 120 RD 120
ENDCOLLECT "lowerarm_movement
SETSCALE .5 .5 .5
BALL
UP 0.5 EAST .15
SETSCALE .1 1 .2
BOX
WEST .3
BOX
EAST .15
UP 0.5
; wrist
SETMAT 0 8
SETSCALE 1 1 1
TRANSFORM
MAKE "wrist OBJECT
SETPARENT :wrist
SETSCALE .5 .5 .5
BALL
SELECT OBJECT
SETIT 2 31
DESELECT
UP .3
CONE
SELECT OBJECT
SETIT 2 31
DESELECT
; make it move
SPIN :roboarm "lt 20
ORIENT :upperarm :upperarm_movement 10
ORIENT :lowerarm :lowerarm_movement 15
SPIN :wrist "lt 8

I am still wondering how a robotic arm is controlled and commanded to perform tasks. Certainly some robotic arms have sensors to tell distance, colours, and even visual imagery processing. In this virtual robotic arm, I am interested in pointing to a particular point with its tip in its reach. The mathematics seems complex so I will leave to future work when I got time to work it out. (Note: I have made another virtual robotic arm with controls. Click on this link to play.)

Please leave a comment if you have any tips for robotic arm movment. :-)

Files: robotic_arm.x3d | robotic_arm.logo