Register to reply

Method to Locate Footstep

by Frederick84
Tags: footstep, locate, method
Share this thread:
Frederick84
#1
Feb8-10, 11:33 AM
P: 2
Hi,

I am working on a project to collect data on walking gait of patient, ie stoke patient. I need solution to locate the position of the patient's feet and the distance apart by using just distance sensor.

any one got good idea ??
Phys.Org News Partner Science news on Phys.org
FIXD tells car drivers via smartphone what is wrong
Team pioneers strategy for creating new materials
Team defines new biodiversity metric
minger
#2
Feb8-10, 12:13 PM
Sci Advisor
P: 1,498
How precise, complex are you looking for? Would something as simple as dipping their feet in ink and having them walk on paper work?
Frederick84
#3
Feb8-10, 12:23 PM
P: 2
Quote Quote by minger View Post
How precise, complex are you looking for? Would something as simple as dipping their feet in ink and having them walk on paper work?
Cause, Im planning to place a distance sensor on the foot, then use them to meaure the distance, however it cant locate the position.

As i need the data to be transfer via RS232 to matlab to generate the results, therefore I cant use the method you suggested.

Thank for the input.

Danger
#4
Feb11-10, 11:40 AM
PF Gold
Danger's Avatar
P: 8,964
Method to Locate Footstep

Perhaps it would be useful to contact an optical effects company such as Industrial Light and Magic. A lot of CGI characters are based upon motion studies of live actors. I think that most of those are accomplished using laser scanning, but the first efforts involved sensors such as magnetic, radar, acoustic, and simple radio transmitters. A professional in the business might be able to give you some really great insights.
My personal approach, being an uneducated amateur, would probably be to use an RF transmitter with triangulating receivers.
berkeman
#5
Feb11-10, 12:00 PM
Mentor
berkeman's Avatar
P: 41,096
I like Danger's ILM idea. You can use the video pickup technique, which is very well developed. Put little white marker balls on parts of the feet and legs, and use a video camera to film the patiet's gait on a treadmill. You can film from both sides if bilateral data are important.
Danger
#6
Feb11-10, 12:21 PM
PF Gold
Danger's Avatar
P: 8,964
Quote Quote by berkeman View Post
You can film from both sides if bilateral data are important.
Actually, the only reason that I didn't mention optical sensing is because I considered it to be two-dimensional v/s the 3 that Frederick seems to need. Multi-angle vision would cover that nicely, as long as the inputs remain properly co-ordinated. Good call.
timmay
#7
Feb12-10, 09:46 AM
P: 122
Gait analysis is often carried out using pressure sensing panels or footplates. One system I've used before is made by Tekscan.

Alternatively, a very basic system of digital image correlation using two cameras could be carried out as suggested above. Have a marker on both shoes/feet, make sure your two cameras (mounted at an angle of ~20deg to each other or so) can both see the marker clearly, then track the motion of the marker between synchronised frames. DIC does this with many many markers, and in a stereoscopic configuration of cameras can give you three dimensional position data.


Register to reply

Related Discussions
Locate crashed aircraft General Physics 7
Locate the position of the image. Introductory Physics Homework 4
Where to locate this prob on the forum? General Math 0
Locate the centroid Introductory Physics Homework 2
Help me locate HST images. Astronomy & Astrophysics 5