Table 3.

Table of symbols

Symbol	Meaning
x 0	Reference position
x h	Head position relative to reference (83)
x g	Grasper position relative to reference (83)
xg/h = xg − xh	Grasper position relative to head
Ni	Boolean state of neuron i
Ai	Muscle activation associated with muscle i
Ti	Muscle tension associated with muscle i
τm	Muscle activation time constant
ch	Damping coefficient for head movements
cg	Damping coefficient for grasper movements
T I2	I2 protractor muscle tension (79)
T I3	I3 retractor muscle tension (76)
T hinge	Hinge muscle tension (81)
P I4	Grasper pressure (72)
P I3,ant.	Anterior I3 pinch pressure (74)
F I2	I2 protractor muscle force (85)
F I3	I3 retractor muscle force (87)
F hinge	Hinge muscle force (88)
F I4	Grasper closing force (90)
F I3,ant.	Anterior I3 pinch force (100)
F I2,max	Scaling parameter for I2 protractor muscle force
F I3,max	Scaling parameter for I3 retractor muscle force
F hinge,max	Scaling parameter for hinge muscle force
F I4,max	Scaling parameter for grasper closing force
F I3,ant.,max	Scaling parameter for anterior I3 pinch force
Fh	Net force on head (97)
Fg	Net force on grasper (84)
F o	Net force on object, force on transducer during swallowing (104)
[hinge stretched] =[xg/h > 0.5]	Boolean state of hinge stretch
[unbroken] =[Fo ≤ zs]	Boolean state of seaweed unbroken
[lipschem]	Boolean state of chemical stimulus at lips
[lipsmech]	Boolean state of mechanical stimulus at lips
[graspermech]	Boolean state of mechanical stimulus in grasper
Kg	Grasper spring constant
Kh	Head spring constant
$x_{g∕h}^0$	Rest length of grasper spring
$x_h^0$	Rest length of the head spring
μs,g	Coefficient of static friction between grasper and seaweed
μk,g	Coefficient of kinetic friction between grasper and seaweed
μs,h	Coefficient of static friction between head (jaws) and seaweed
μk,h	Coefficient of kinetic friction between head (jaws) and seaweed