intro to movement planning

Question 1

what is the general rule of Fitt’s law

Answer 1

the more accurate the movement, the slower the movement becomes

Question 2

briefly describe the two-third power law

Answer 2

when making curved movements, it becomes slower the more curved .

power of curvature is proportional to velocity

Question 3

what elements does a robot arm need to consider before picking up an apple

Answer 3

localisation and planning

execution and control

adaptation

Question 4

what is space

Answer 4

set of points with some added structures

Question 5

if a model has locations labelled through xyz coordinates what type of space is displayed

Answer 5

effector space
task space
operational space

Question 6

if a model has locations labelled through joint angles what types of space would be displayed

Answer 6

configuration space
joint angle space
body space

Question 7

what are coordinates

Answer 7

set of numbers that uniquely define numbers in space

Question 8

what is a coordinate/reference frame

Answer 8

a single space with multiple coordinate systems

Question 9

cartesian coordinate system

Answer 9

defines 3 points in space
xyz coords

Question 10

cylindrical coord system

Answer 10

defines how far a point is within one plane

the angle between the direction of the point and the x axis

Question 11

spherical coordinates system

Answer 11

uses different angles and distances

Question 12

egocentric coords

Answer 12

System is attached to the body

e.g. POV in vid game

Question 13

allocentric coords

Answer 13

system is attached to the external world/object

e.g. 3rd person view in vid game

Question 14

inverse kinematics

Answer 14

end effector space to configuration space

Question 15

forward kinematics.

Answer 15

configuration space to end effector

Question 16

what is meant by redundancy in terms of kinematics

Answer 16

kinematics don’t always have a SINGLE solution

finger can be art same point but can have different joint angles

Question 17

what type of kinematics is redundant

Answer 17

inverse

Question 18

what is dynamics

Answer 18

kinetics

adding forces to torques

Question 19

what is linear vs angular kinematics

Answer 19

distance vs angles

Question 20

what is linear vs angular kinetics

Answer 20

forces vs torques

Question 21

what is inverse dynamics

Answer 21

kinematics to kinetics

Question 22

what is forward dynamics

Answer 22

kinetics to kinematics

Question 23

what equation in terms of newtons second law describes relationship between kinematics and dynamics

Answer 23

force = inertia x acceleration

force and acceleration are vectors of forces and torques

Question 24

what is a feedforward open loop of control

Answer 24

movement pre planned / pre determined

Question 25

pros of feedforward loop

Answer 25

movement can be controlled without requiring external info good for fast movement

Question 26

cons of feedforward control

Answer 26

errors can accumulate overtime no flexibility with environment high cost of planning - no generalisation

Question 27

what is a feedback closed loop of control

Answer 27

uses feedback from environment to predict/produce movement

Question 28

pros of feedback control

Answer 28

flexible - deals w unexpected events robust - control error doesn't accumulate general - control is invariant to starting or goal position

Question 29

cons of feedback control

Answer 29

time consuming can become unstable if feedback is noisy and when feedback gain is high can be unstable when feedback is delayed

Question 30

what is meant by variability

Answer 30

when same movement is repeated, uncertainties can change the movement pattern insight into brain control strategy