ELEC 391 - Robotics
1
Autonomous Motion-Control System
Master Slave
Carry out
intended task
Side-effects
of actions
Pre-defined task
No human in the loop
Smart: ability to INTERPRET & make decisions
Interpret: derive INTENT from information provided
Master
• Achieves outcome in physical world
• Sends low-level commands to slave
Dumb
• Prescribed trajectory
• No real-time decisions made
Intelligent
• Computer logic / AI
• Responds to FB from physical system
Slave
• Carries out low-level commands
• May send sensor data to master
Dumb
• Joint-space
• Open-loop control
Intelligent
• Task-space → coordinated motion
• Closed-loop control
• Robot
ELEC 391 - Robotics
2
Path Speed
Faster
Slower
Scale time axis of desired path
Coordinated Motion Trajectory
Very Nice : Continuous 2nd Derivative
Nice : Discontinuous 2nd Derivative
Not Nice : Discontinuous 1st Derivative
: Discontinuous Path
ELEC 391 - Robotics
3
Path Continuity
Joint-Space : Discontinuous path
Task Space : Coordinated motion path
start
end
Surgical Plan
Robodoc.com
Thinksurgical.com
coronal medial
transverse
ELEC 391 - Robotics
4
Laser Vision Correction (Lasik)
• Laser in-situ
keratomileusis
• Optical robot
• Small motion range
• Very fast
ARTAS Hair Restoration
• Course/Fine Robot
• OTS KUKA arm
• Custom end-effector
• Repetitive path
• Implant hair follicles
ELEC 391 - Robotics
5
Tele-Op Motion-Control System
Master Slave
Carry out
intended task
Side-effects
of actions
Tele-Operation
• Put human somewhere
– they don’t fit
– is dangerous
– is far away
• Augment human
– Position resolution
• Motion scaling
– Sensory resolution
• Force scaling
• Master (I/P Device)
– Passive
• P (mouse)
• F (3D mouse)
– Active
• PP
• PF
• FP
ELEC 391 - Robotics
6
Passive Master
Task Outcome
෍
+
_
PID
Control
Slave
Robot
Pos
Sensor
Passive
Master
Active Master  P-P Control Example
Work
Site
෍
+
_
PID
Control
Master
Robot
Pos
Sensor
෍
+
+
Outcome෍+
_
PID
Control
Slave
Robot
Pos
Sensor
෍
+
+
ELEC 391 - Robotics
7
General Purpose
Intuitivesurgical.com
Master (semi-active) Slave
Verb
Flex
ELEC 391 - Robotics
8
Atrial Fibrillation Ablation
Ablate conduction paths in Atrium Hansenmedical.com
LARA
LVRVMaster (active) Slave
Makosurgical.com
Master & Slave
THA / TKA
Guidance System – Combined Master/Slave
Impedance Control