Z
zipzit
- Jan 1, 1970
- 0
Looking for some design ideas...
I'm would like to build a lap timer for athletes who travel around on
a short track. Track size is 100M... (entire track floor size is 100 x
200 feet).
--I'm assuming a small device each athlete carries on tight waistband
(like a CD/MP3 player butt pack...)Obviously smaller is better. This
device would then transmit info on laptimes to a base station..
--Finish and start times absolute do NOT matter. The only thing the
coach really watches is lap time splits. These guys change lead so
often in practice who is in first doesn't really matter, its easy to
see who is where. Today's constant stopwatch work the coach has to do
is pretty disruptive. Rather than focussing on the athletes, he is
always watching the watch.
--Track is generally indoors (i.e. likely no GPS... and I'm not into
Pseudolites... although it is an option, I doubt it is cost
effective.)
--Needs to be reasonably inexpensive.
--Must be non-evasive to the track. I can't place cable overhead, or
under the floor. No way, no how. I think that kills radio frequency
Identification (RFID) ideas.
--Lap accuracy should be to nearest tenth of a second. I can wait for
up to two seconds after lap measurement zone for a display. I would
hope to get up to six athletes measuring at the same time. Lap times
should be in range of 9 seconds up to 15 seconds/lap depending on
drills.
The only thing I can come up with is a battery operated weak RF
transmitter, located somewhere along the side of the track. Each
individual unit includes a RF receiver, which looks for a signal
minimum threshold (T). The individual recievers measure lap start
time as (threshold boundary in (i) + threshold boundary out (i))/2 .
Lap finish time (threshold boundary in (i+1) + threshold boundary out
(i+1))/2. I would then send lap time to base station (laptop or PDA
with WI-Fi or Zigbee card...)
In ascii:
*
Athlete * *
-------> --------T(in)-------------T(out)----------->
Path * *
* *
* R *
F
* *
* *
* *
* *
*
RF Source is off track. T = RF Power Threshold * = RF power.
This is an idea I've been toying with in my head. Anybody else have
suggestions?
Many thanks, LB
Temporily in Chicago, IL
I'm would like to build a lap timer for athletes who travel around on
a short track. Track size is 100M... (entire track floor size is 100 x
200 feet).
--I'm assuming a small device each athlete carries on tight waistband
(like a CD/MP3 player butt pack...)Obviously smaller is better. This
device would then transmit info on laptimes to a base station..
--Finish and start times absolute do NOT matter. The only thing the
coach really watches is lap time splits. These guys change lead so
often in practice who is in first doesn't really matter, its easy to
see who is where. Today's constant stopwatch work the coach has to do
is pretty disruptive. Rather than focussing on the athletes, he is
always watching the watch.
--Track is generally indoors (i.e. likely no GPS... and I'm not into
Pseudolites... although it is an option, I doubt it is cost
effective.)
--Needs to be reasonably inexpensive.
--Must be non-evasive to the track. I can't place cable overhead, or
under the floor. No way, no how. I think that kills radio frequency
Identification (RFID) ideas.
--Lap accuracy should be to nearest tenth of a second. I can wait for
up to two seconds after lap measurement zone for a display. I would
hope to get up to six athletes measuring at the same time. Lap times
should be in range of 9 seconds up to 15 seconds/lap depending on
drills.
The only thing I can come up with is a battery operated weak RF
transmitter, located somewhere along the side of the track. Each
individual unit includes a RF receiver, which looks for a signal
minimum threshold (T). The individual recievers measure lap start
time as (threshold boundary in (i) + threshold boundary out (i))/2 .
Lap finish time (threshold boundary in (i+1) + threshold boundary out
(i+1))/2. I would then send lap time to base station (laptop or PDA
with WI-Fi or Zigbee card...)
In ascii:
*
Athlete * *
-------> --------T(in)-------------T(out)----------->
Path * *
* *
* R *
F
* *
* *
* *
* *
*
RF Source is off track. T = RF Power Threshold * = RF power.
This is an idea I've been toying with in my head. Anybody else have
suggestions?
Many thanks, LB
Temporily in Chicago, IL