Biomechanics is a rising field of interest for many different people from medicine to sports and even into the arts. The human body can be monitored in a variety of ways from eegs which measure brain waves, eogs to measure eye movement in sleep studies, heart and breathing monitors in hospitals but many would like the ability to measure certain things outsside of a clinical environment. Many companies work to bring these types of interfaces to daily life. So that we could monitor our own bodies as we would our cars in a continuous way. But how can we measure these things while we live our life with out inhibiting us from doing the things that we do on a normal basis. We cannot go through an obstacle course or dance through an environment connected to a wall in a hospital. Wireless technology has grown leaps and bounds and will make many new things possible that have not been in the past. My own personal interests remain within the arts and with movement as a control of environment, whether that environment be auditory or visual or stimulate any other sense for that matter. The depth of research into this world is an abyss that seems to be come ever deeper the more one learns about the subject. fortunately the class is limited to the lower body, and starting form there know that i am only scratching the surface.
I will develop a first draft prototype of sensor possibilities for retrieving information from things such as joint angles and rotations and if possible muscle stretch or tension you could also measure pressure for, lets say weight displacement on the plantar surface of the foot. I'll use the fancy words and try to come up with some solid ideas which could be incorporated into an abstracted prototype to get a grant so that i could actually build such a thing at a later date. video can be used to track motion
troika ranch also develoved a system that measures flexion on eight joints

There are limited possibilities of movement inferior to the transverse plane and only six large joints which will be main points of interest for monitoring movement for this paper.
the hips
the knees
and the ankles
The six joints can be looked at in pairs because we have two legs last time i checked though each individual joint acts independently of all other joints. With the muscles this can be increased to a more complicated system but i do not at this time know of ways to measure the individual muscles through out the body. Until I do i will concern my self with the larger movements of the skeletal system. Our main limitation is that the human body can can only as of yet be interfaced superficially. This leads to problems measuring human movement because joints which could be hard to measure on their own are even harder to access because they are deep to certain muscle groups and skin. We will for the sake of simplicity began with the anatomical position as unity or a starting state/natural state since most joints are in their natural state of extension in this position. Starting with the superior structure the hips and working down towards the inferior ankles. When dealing with the hips circumduction becomes a problem because of the 3d conic movement of a ball and socket joint. The closest electronic analog i can think of is a joystick which measures potentiometers on two axis and outputs both position values like coordinates. if we wereto use a flex sensor we could only measure the anterior hip motion along the the sagital plane because of the gluteus maximus and hamstrings on the posterior which mask the small angle of movement we could measure if we had access to the acetabulum where the head of the femur makes contact with the coxal bone. One might be able to measure the movement of the greater trochanter but that would still be difficult with the muscles which act as the flexors of the hip joint. This problem holds firm when you try to measure abduction(open) and adduction(closed) on the frontal plane as you would see it in Leonardo's "Anatomy." {as a side note measuring the medial and lateral rotation would be difficult as well} The knees being a hinge joint are the only joint on the lower body that can be easilly monitored using a flex sensor. Hinge joints lend themselves to this type of monitoring because they have one state of extension and one state of variable flexion from 180 degrees all the way open down to about 10 degrees as folded as possible. Flex sensors aren't really useful for any other type of synovial joint. on to the ankle
Measuring the ankle is weird because its natural state of extension lies between two points of flexion dorsiflexion with the toe up and plantarflexion with the toe down on could put flex sensors along the achiles tendon and the dorsal part of the foot where the tibia and fibula meat the talus. more of the foot could be wired up to flex sensors for each of the phalanges and metatarsals but the shoe probably wouldn't be very comfortable. for the foot i would like to develop some sort of measurement device that would be more intricate but similar to the type of system that you see in children's flashing led shoes. the system would have quite a few pressure sensors embedded in the soul of the shoe to measure the anterior most end of the metatarsals and through out the phalanges and cuboid area and also below the calcaneus to measure the weight displacements as a dancer moved and balanced in different ways. It could get complex.
In my search for better sensors I came across some interesting developers and their websites
i found this website porcupine these porcupines are tilt / ball switches which recognize motion and poses on the three planes could be quite useful.
I also found a similar sensor (the coolest one). at it reads full 3d motion and comes with software i don't even want to ask how much is costs it uses small blocks which could be fitted to the femur and the tibia/ fibula and would send out information about the orientation of those bones really really useful stuff it also says how fast it moves etc check it out. also there is a book called Three dimensional analysis of human movement which is essays of many different scientists edited by Paul Allard
three d analysis
what of the human body as a sensor
to measure anothers source to monitor
out put in a personal way

its what interactive art is all about

how did it feel

adam overtons work
like performance art it has such depth
take your pulse take your neihbors pulse

old monitors strings pulling spring loaded bows bowing on strings another person pulling on an arm controling the tension on a string
poleema sensors use magnetic feilds to determine location