3 DoF - answers✔✔How many DoF in Acriomioclavicular Joint
Hip, but GHJ has more mobility - tradeoff - answers✔✔Which has more stability hip or GHJ?
Kinetics
kinematics
anthropometric - answers✔✔What are the 3 different data you need for inverse dynamics?
study of forces which cause movement (Forces) - answers✔✔Kinetics
Position in time (acceleration) - study of describing motion - answers✔✔Kinematics
study of physical shapes and sizes of humans (mass) - answers✔✔Anthropometric
2 cameras - answers✔✔What is the minimum number of cameras you need for 3D motion?
Stance and swing phase - answers✔✔What are the phases of gait?
the foot we are looking at is on the ground (60% during walking and 50% during running) -
answers✔✔Define stance phase
the foot we are looking at is off the ground (40% during walking and 50% in running) -
answers✔✔Define swing phase
The length of one position of one foot to the same position of the same foot - answers✔✔What is a
stride?
,length of one foot at a certain position to the same position on the other foot - answers✔✔What is a
step?
2 - answers✔✔How many steps in a stride?
steps/minute or strides/minute - answers✔✔What is cadence?
shorter steps but bigger steps make you less stable - answers✔✔do you expend more energy by taking
short or long steps?
inverted V, goes to extension and then back to flexion - answers✔✔What does the joint angles of hip
look like in the sagittal plane?
does a little bit of flexion and then goes back down for extension and then a huge flexion -
answers✔✔What does the joint angles of knee look like in the sagittal plane?
dips down a little bit for extension and then slowly climbs for flexion and does a big dip in extension and
then climbs back up for flexion again - answers✔✔What does the joint angles of ankle look like in the
sagittal plane?
- inverted pendulum
- converting kinetic energy to potential
- the more effective you are at converting it the more effective we can control that motion -
answers✔✔What is bipedal locomotion?
Fr = v^2/gL
- as speed gets to certain threshold, you start to walk so fast that it becomes a run and you change
Froude's number - answers✔✔What is Froude's number?
at the midtance - answers✔✔When is the CoM the highest?
, you're expending unnecessary energy - answers✔✔What happens when you're walking side to side
- step length (avg. 0.5m)
- cadence (speed)
- duration of single leg stance (not too long)
- walking speed
- ratio of pelvic span to ankle spread (feet are closer so you expend less energy but less stability) -
answers✔✔What are characteristics of mature walking gait?
1) Heel strike
2) Foot flat
3) Mid-stance
4) Heel off
5) Toe off - answers✔✔What are the 5 stages of the stance phase?
- pelvic rotation
- pelvic list
- knee flexion during stance
- coordinated movements of knee, ankle and foot
- lateral displacement of body CoM - answers✔✔What are the 5 determinants of gait?
- rotates about vertical axis alternatively to left and right
- approx. 4 degrees to either side
- intersections of successive arcs are rendered less abrupt
- force required to change direction of CoM decreased
- angular displacement of hip in flexion and extension is decreased - answers✔✔What is pelvic rotation
(gait)?
- lists downward in coronal plane to side opposite weight-bearing limb