Racecar timing and track condition alert system and method

In a preferred embodiment, one or more timing stations disposed around a racecar track. At each station, a timing signal in the form of a repeating or oscillating beam of laser light causes a photodetector mounted on a racecar to turn on and off, the photodetector outputting a stream of electrical pulses. A microprocessor associated with the photodetector receives the stream of pulses, determines the real time when the signal is received, and stores that real time. When the microprocessor receives an RF polling signal, unique to that racecar, from a base station, the microprocessor transmits the real time data to the base station. When a second timing signal is received from the same or a second timing station, a second real time is determined, stored, and transmitted to the base station. The base station then computes the difference between the two real times. The base station processes data from all racecars in a race by sequentially polling the racecars. Different pulse rates are employed at different timing stations and recognized by the microprocessors so that lap time, total time, time through corners, and time in pit stops can be determined for each racecar. In a further embodiment, there is provided an on-board track condition display responsive to signals transmitted from the base station to the racecars.

BACKGROUND OF THE INVENTION 
1. Field of the Invention 
The present invention relates to the timing of racecars generally and, more 
particularly, to a novel system for timing racecars which is automatic and 
eliminates the need for manually operated mechanical devices and for 
giving racecars drivers automatic and on-board indication of racetrack 
conditions. 
2. Background Art 
From its beginnings in the late 1800's automobile racing has become a 
popular participant and spectator sport, flourishing in all major western 
nations of the world, drawing huge spectator crowds, and stimulating large 
financial investment by automobile manufacturers. Formal automobile race 
courses or tracks range from small dirt surface tracks to those which are 
paved and may be three to four miles to the lap. Total distances raced on 
the later may range from 150 to 400 miles. 
The winner of such a race, of course, is the driver who completes the total 
distance in the least amount of time. Conventionally, such time is 
determined by manually operated stopwatches or similar mechanical devices, 
with one stopwatch required for each car. This system has the advantage of 
low cost but has the disadvantage of necessitating recruiting perhaps a 
relatively large number of people in one place, but also has the further 
disadvantage of introducing human error into the timing process. Also, 
backup personnel are required to assist the timers in identifying the cars 
that pass the start/finish line. The manual method is further complicated 
in that timing may be suspended when there is an accident or hazardous 
situation present on the track. The processing of the data takes a great 
deal of time and, consequently, the complete results of a race may be 
delay for hours. The manual method also makes difficult the recording of 
times through corners and times in pit stops. 
One non-manual system that is used for racecar timing includes computerized 
racecars that are equipped with magnetic sensors attached beneath the 
cars, which sensors are responsive to magnetic stripes affixed to the 
track. This system is relatively expensive to install and is not 
particularly satisfactory, in that the magnetic stripes are very 
susceptible to damage, due to the racecars driving over them. 
In addition to determining the total time for each car, other time 
intervals are of interest. These include: determining the time for each 
car to traverse each lap, determining the time a car stops in a pit for 
service, and determining the time for each car to traverse a corner. Each 
additional such input requires additional human effort with the 
concomitant multiplying of opportunities for human error. 
As part of the procedure for conducting a race, signal flags are used to 
indicate track conditions to the racecar drivers. For example, the display 
of a green flag signals to the drivers that track conditions are clear. A 
yellow flag indicates an accident ahead. A red flag signals the drivers to 
stop immediately. A major disadvantage of such a procedure is that 
communications must be accurately made with those persons manning the flag 
stations so that the proper flags are displayed in the proper locations. A 
serious disadvantage si that they may be delay in displaying the proper 
flags and/or delay in the drivers seeing the flags. 
Accordingly, it is a principal object of the present invention to provide a 
system and method for automobile racecar timing that is automatic and 
requires no human operations. 
It is another object of the invention to provide such a system and method 
that is highly accurate. 
It is a further object of the invention to provide such a system and method 
that can be used to determine the time a racecar takes to traverse each 
lap or part of a lap, to determine the time a racecar takes to traverse 
each corner, and the time a racecar is stopped in a pit. 
It is an additional object of the invention to provide such a system and 
method that is economical and easily retrofitted to existing racetracks 
and racecars. 
It is yet another object of the invention to provide means by which 
elements of the racecar timing system and method can be employed to give 
racecar drivers automatic and on-board indication of track conditions. 
Other objects of the present invention, as well as particular features and 
advantages thereof, will be elucidated in, or be apparent from, the 
following description and the accompanying drawing figures. 
SUMMARY OF THE INVENTION 
The present invention achieves the above objects, among others, by 
providing, in a preferred embodiment, one or more timing stations disposed 
around a racecar track. At each station, a timing signal in the form of a 
repeating or oscillating beam of laser light causes a photodetector 
mounted on a racecar to turn on and off, the photodetector outputting a 
stream of electrical pulses. A microprocessor associated with the 
photodetector receives the stream of pulses, determines the real time when 
the signal is received, and stores that real time. When the microprocessor 
receives an RF polling signal, unique to that racecar, from a base 
station, the microprocessor transmits the real time data to the base 
station. When a second timing signal is received from the same or a second 
timing station, a second real time is determined, stored, and transmitted 
to the base station. The base station then computes the difference between 
the two real times. The base station processes data from all racecars in a 
race by sequentially polling the racecars. Different pulse rates are 
employed at different timing stations and recognized by the microprocessor 
so that lap time, total time, time through corners, and time in pit stops 
can be determined for each racecar. 
In a further embodiment, there is provided an on-board track condition 
display responsive to signals transmitted from the base station to the 
racecars.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS 
Referring now to the Drawing, in which similar or identical elements are 
given consistent identifying numerals throughout the various figures 
thereof, FIG. 1 illustrates a racetrack, generally indicated by the 
reference numeral 10, which employs some elements of the present 
invention, namely, timing stations 12, and 14-23, the details of which 
will be described later. 
Timing station 12 is located so as to provide timing signals for the 
determination of lap time for each racecar, such as racecar 50. Timing 
station pair 14/15 is located so as to determine the time a racecar is in 
pit 30, with station 14 providing a timing signal when a racecar enters 
the pit and station 15 providing a timing signal when the racecar leaves 
the pit. Similarly, timing station pairs 16/17, 18/19, 20/21, and 22/23 
are located so as to provide timing signals in and out of the four corners 
of track 10, with, for example, station 16 providing a timing signal as a 
racecar enters the upper lefthand corner of the track and station 17 
providing a timing signal as the racecar leaves that corner. 
Referring now to FIG. 2, the operation of timing station 12 is illustrated. 
Timing station 12 includes laser scanner 40 mounted on a support 44, the 
scanner being disposed so as to sweep a beam of laser light, which may be 
visible light or in some other frequency range, across track 10 through an 
angle "A" in a plane orthogonal to the major axis of the track, with the 
laser light falling on a row of racecars 50, 51, 52, and 53 shown side by 
side for illustrative purposes. Preferably, a second laser scanner 42 
mounted on a support 48 is disposed so as to sweep a second beam of laser 
light across track 10 through an angle "B" in the same plane as the laser 
light from scanner 40, but from a direction opposite from that of the 
laser light from scanner 40. The purpose of providing two scanners 40 and 
44 will be discussed later. 
Racecars 50-53 have disposed on the roofs thereof optical receivers 60, 61, 
62, and 63, respectively. It will be understood that as racecars 50-53 
pass through timing station 12, the light beams from laser scanners 40 and 
42 will fall on optical receivers 60-63. 
Referring now to FIGS. 3 and 4, there is illustrated the construction of 
the optical receivers, here, for example, optical receiver 60. Optical 
receiver 60 includes a base member 68 on which are mounted photodetectors 
70-75 which receive, respectively, laser light focussed by lenses 76-81. 
Lenses 76-81 have associated light tunnels 82-87, respectively, disposed 
so as to conduct laser light to the lenses and so as to minimize the 
effect of sunlight and stray light. It will be understood that base member 
68 is mounted to the roof of a racecar (not shown) and that the racecar is 
moving in the direction of the arrow on FIG. 3. So positioned, 
photodetectors 70-72 will receive laser light from, for example, laser 
scanner 40 (FIG. 2). Since laser scanner 40 is providing a repeating or 
oscillating beam of light, photodetectors 70-72 will be turned on by a 
series of light beams, here indicated by "A1"-"A9". Likewise, 
photodetectors 73-75, which are aligned in a bank side by side with the 
bank of photodetectors 70-72, will receive light beams "B1"-"B9" from 
laser scanner 42 as the racecar passes through timing station 12. The 
number of such light beams received at any given timing station will 
depend on the rate of oscillation and the speed of the racecar. For 
example, with a laser scanner outputting a scan at the rate of 2OOO sweeps 
per second, a 10-inch long bank of photodetectors will receive about 5 
pulses at a timing station when the racecar is traveling 240 mph. 
It will be seen from FIG. 4 that the light tunnels and lenses, here light 
tunnel/lens pairs 84/78 and 8/81 are mounted on supports 92 and 94, 
respectively, at an angle to the plane of base member 68 so that the light 
tunnel/lens pairs are aligned generally with the beams of light from laser 
scanners 40 and 42. 
Also mounted on base member 68 is a package of electronic circuitry 90 the 
function of which will be described later. 
It will be understood that optical receiver 60 may be fitted with a 
suitable cover member (not shown). 
Referring again to FIG. 1, in order to distinguish between various timing 
stations, a different sweep rate is employed depending on the type of 
timing station. For example, the 2000 sps (sweeps per second) rate may be 
chosen for timing station 12. Since racecars reduce speed for corners, a 
sweep rate of 1000 sps can be used at timing stations at corners, such as 
timing stations 16/17, and, since racecars have greatly reduced speed when 
entering or leaving a pit, a sweep rate of 500 sps can be used at timing 
stations 14/15 at pit 30. 
FIGS. 5 and 6 illustrate embodiments of laser scanners which may be 
employed to provide the sweeping laser beams across racetrack 10 and one 
or the other types of which, it will be understood, would be mounted in 
laser scanners 40 and 42 (FIG. 2). In FIG. 5, a laser scanner, generally 
indicated by the reference numeral 100, includes a laser 102 disposed so 
as to provide laser light to be reflected by a mirror 104 which is mounted 
on a vibrating reed 106. Mounted at the distal end of reed 106 is a 
ferromagnetic armature 108 which is disposed within a gap formed in a 
field electromagnet 110. Flux flow within field electromagnet 110 is 
caused to oscillate by alternating current from an oscillator circuit 112 
supplied to coil 114, thus, in turn, causing armature 108 and vibrating 
reed 106 to alternatingly move between the positions shown in solid lines 
and in broken lines on FIG. 5. This oscillation motion causes the light 
beam to be reflected through an angle "C." This angle is determined by the 
amplitude of the oscillation circuit. Since the light beam reflected by 
mirror 104 sweeps both up and down as reed 106 vibrates, a 1000 Hz. AC 
current will provide 2000 sps of the oscillating light beam. 
In FIG. 6, a laser scanner, generally indicated by the reference numeral 
118, includes a laser 120 disposed so as to provide laser light to be 
reflected by a polygonal mirror 122 which is mounted on a shaft 124 for 
rotation therewith. As polygonal mirror 122 rotates, laser light will 
sweep across racetrack 10 in a repeating beam through an angle "D." Angle 
"D" is theoretically close to 180 degrees, but the usable angle is much 
smaller. With polygonal mirror 122 having 10 faces as shown, a rotational 
speed of 12,000 rpm will produce 2000 sps. 
FIG. 7 illustrates the placement of optical receivers on racecars. Here, 
racecar 50 with optical receiver 60 mounted thereon is shown just touching 
the start/finish line. It can be seen that the plane of laser light swept 
by timing station 12 across racetrack 10 is positioned back from the 
start/finish line a distance "D" which is equal to the distance from the 
front edge of racecar 50 to the front edge of optical sensor 60, the 
latter point being that where the first sweep of laser light will be 
received by the optical sensor. 
Optical sensors may be permanently attached to racecars or they may be 
temporarily attached by means of conventional hook and loop fabrics. Thus, 
the present invention may be easily retrofitted to existing racecars, it 
being completely self-contained and requiring no connection to the 
racecar's electrical system or access by the driver of the racecar. 
Referring now to FIG. 8, there is illustrated schematically the circuitry 
90 by which information derived from the laser light beams is processed, 
assuming that the system of the present invention is employing the three 
pulse rates noted above. Photodetectors 70-75 receive laser light sweeps 
and generate electrical pulses in response thereto. It will be recalled 
from FIG. 3 that photodetectors 70-72 are disposed so as to receive laser 
light sweeps from laser scanner 40 (FIG. 2) and that photodetectors 73-75 
are disposed so as to receive laser light sweeps from laser scanner 42. 
The electrical pulses pass, respectively, through bandpass filters 200-205 
and digitizers 206-211, each bandpass filter/digitizer pair processing 
electrical pulses corresponding to one of the sweep rates, i.e., 0.5K sps, 
1.OK sps, or 2.OK sps. The electrical pulses, i.e., 0.5K pps (pulses per 
second), 1.OK pps, or 2.OK pps, from the two groups of photodetectors, 
70-72 and 73-75, are inputted to a microprocessor 220 through OR gates 222 
and 224, respectively. Microprocessor 220 has associated therewith a 
battery 230, a memory 232, a real time clock 234, an RF 
transmitter/receiver 236, address switches 238, and a local display 240. 
It will be understood that all of the elements shown on FIG. 8, except 
local display 240, are located in optical receiver 60 mounted on racecar 
50. 
Completing the system of the present invention, and illustrated on FIG. 9, 
is a base station, generally indicated by the reference numeral 300. Base 
station 300 includes a central computer 302 with which is associated a 
score-keeping terminal 304, a pit display 306, a printer 308, and an RF 
receiver/transmitter 310. 
With reference also now to the others figures, the operation of the timing 
system of the present invention will be described. 
While the racecars are preparing for the start, computer 302, through RF 
receiver/transmitter 310, first initiates operation of the optical 
receivers on the racecars and initiates operation of the timing stations, 
also setting the desired scan rates according to instructions inputted to 
the computer by score-keeping personnel. Computer 302 then transmits the 
real time to all optical receivers and then polls each to ensure that each 
has correctly received the real time and set its real time clock 
accordingly. Thus, it can be determined that all cars are in 
synchronization and that the RF receivers/transmitters are operational. 
At the start, racecar 50 will cross the start/finish line (FIGS. 1 and 7) 
while passing through timing station 12. Photodetector 72 (FIG. 3) will 
receive 2.OK light sps and convert the same to 2.OK electrical pps which, 
after initial processing, are inputted to microprocessor 220 which 
measures the frequency of the detected pulses. When microprocessor 220 
detects that the frequency of detected pulses is indeed 2.OK pps, the 
microprocessor transfers the time from its real time clock 234 to its 
memory 232. When microprocessor 220 receives from RF transmitter/receiver 
236 a polling signal from central computer 302 (FIG. 9) through RF 
receiver/transmitter 310, the address of which polling signal corresponds 
to an address previously set on address switches 238, the real time stored 
in memory 232 is transmitted to the central computer 302 through RF 
transmitter/receivers 236 and 310 along with an indication of the 
frequency of the timing signal. It is of no consequence that one or more 
racecars may be passing timing station 12 at the same time, since all will 
receive the timing beam virtually simultaneously. 
When racecar 50 again passes through timing station 12, the time of a 
second 2.OK sps signal will be stored and transmitted to central computer 
302 (FIG. 9) during the next polling following the latter event. The 
central computer then subtracts the first time from the second time to 
determine the absolute time it took racecar 50 to circle racetrack 10. The 
foregoing process is reiterated each subsequent time racecar 50 passes 
through timing station 12. Central computer 302 accumulates the total time 
for racecar 50 and can store individual lap times if desired. 
Instantaneous and cumulative information can be provided the score-keeper 
on terminal 304 and to the pit crew on display 306 and printed immediately 
on printer 308 during and/or after the race. 
In order to allow time for processing information and to eliminate the 
possibility of interference with RF transmissions from two or more 
racecars, central computer 302 sequentially polls the racecars. A polling 
rate of five cars per second is satisfactory for most racing conditions. 
When a car is polled, it transmits all data accumulated since the previous 
polling of that car. 
Continuing to refer especially to FIGS. 1, 8, and 9, when racecar 50 
approaches a corner, for example the upper lefthand corner of racetrack 
10, it will pass through a first timing station, here, timing station 16. 
Photodetector 71 now will receive 1.OK sps which, in the manner described 
above with respect to timing station 12, will result in a first real time 
being stored in memory 232 and transmitted to central computer 302 at the 
next polling. Now, when racecar 50 passes through timing station 17, a 
second 1.OK sps will be received and a second real time will be stored and 
subsequently transmitted. Central computer 302 will then compute the 
difference between the two real times. Because of the order of corners 
passed by racecar 50 with respect to each other and to a reference such as 
timing station 12, it will be apparent which corner is being reported. 
Still referring to FIGS. 1, 8, and 9, when racecar 14 passes through timing 
station 14, a 0.5K sps will be received by photodetector 70 and a first 
time stored and transmitted as described above. Likewise, a second 0.5K 
sps received at timing station 15 will result in the time in the pit stop 
being computed by central computer 302. 
Should the race be suspended for a period of time, due to an incident on 
track 10, such information can be separately inputted to central computer 
302 which will appropriately account for that period of time. Likewise, 
penalty times can be similarly inputted. 
In order to allow for spurious pulses in the detecting system, 
microprocessor 220 (FIG. 8) is programmed to determine a time only after a 
given number of pulses are received. For example, microprocessor 220 can 
be programmed to determine a real time only after receiving a selected 
number of pulses at one of the frequencies employed. For example, when the 
first pulse is received, the computer notes the real time and then looks 
for two additional pulses spaced apart by the appropriate time intervals. 
After those pulses are received, the real time previously noted is stored. 
Should the parameters of racecar speed and beam scan rate so dictate, 
multiple photodetectors may be employed for each beam scan rate to assure 
that a minimum number of pulses are received at each timing station. 
With two sets of photodetectors, such as photodetectors 70-72 and 73-75 
(FIG. 3), facing sideways from opposite sides of racecar 50 toward laser 
scanners 40 and 42 FIG. 2), respectively, there are two separate sets of 
electrical pulse inputs to microprocessor 220. This redundancy can be used 
to indicated that valid light pulses are being received and also to 
compensate for sunlight or track lighting. In the latter situations, the 
one of the sets of photodetectors 70-72 or 73-75 receiving sunlight or 
track lighting will output a continuous electrical signal. This will 
result in no data input from that channel to microprocessor 220 which will 
then rely on the input from the other of the photodetectors. 
Differential time measurements from microprocessor 220 may also be sent to 
a local display 240 located in racecar 50. Although the use of such 
displays is generally not permitted during a race, display 246 can be of 
assistance to a driver during practice trials. 
FIG. 10 illustrates how the system and method of the present invention can 
be employed to furnish on-board track condition information to the driver 
of racecar 50. Here, local display 240 connected to microprocessor 220 
(See also FIG. 8.) is mounted at the lower edge of windshield 398 of 
racecar 50. Included in local display 240 are a green light 400 (shown 
lighted, indicating that conditions are clear), a yellow light 402, and a 
red light (404). 
When a hazardous condition exists, an appropriate entry to computer 302 in 
base station 300 (FIG. 9) will cause RF receiver/transmitter 310 (FIG. 9) 
to transmit a signal to RF transmitter receiver 236 (FIG. 8) connected to 
microprocessor 220. Microprocessor 220 will activate local display 240 to 
extinguish green light 400 and to light yellow light 402, thus alerting 
the driver of racecar 50 that a hazardous condition exists ahead. Because 
the locations of all racecars are known, due to the timing signals 
received from timing stations 12-23, only those racecars approaching the 
hazard will receive the hazardous condition signal. For example, if a 
hazardous condition exists at the lower right hand corner of track 10 
(FIG. 1), racecar 50 would receive the hazardous condition signal once it 
passed timing station 19 and the hazardous condition signal would be 
removed once that racecar passed timing station 21. Thus, once the 
hazardous location is entered into computer 302, all racecars receive the 
hazard warning automatically, but only as they approach the hazard. The 
location of local display 240 ensures that the driver of racecar 50 will 
immediately be alerted to the track conditions prior to approaching the 
flags stations. Thus, use of the present invention greatly improves the 
safety of racecar driving. 
Should it be necessary to stop all racecars, the "red" stop signal would be 
transmitted to all racecars simultaneously. 
While only the three most critical lights are shown in local display 240, 
it will be understood that additional lights, corresponding to other 
signal flags, may also be included in local display 240. 
It is within the intent of the present invention that some of the computing 
functions performed by central computer 302 (FIG. 9) may also be performed 
by microprocessor 220 (FIG. 8). 
It will be understood that the system of the present invention can easily 
be retrofitted to existing racetracks and racecars and can be made 
portable. The system is constructed of highly reliable components and a 
minimum number of manual inputs is required. 
It will thus be seen that the objects set forth above, among those 
elucidated in, or made apparent from, the preceding description, are 
efficiently attained and, since certain changes may be made in the above 
construction without departing from the scope of the invention, it is 
intended that all matter contained in the above description or shown on 
the accompanying drawing figures shall be interpreted as illustrative only 
and not in a limiting sense. 
It is also to be understood that the following claims are intended to cover 
all of the generic and specific features of the invention herein described 
and all statements of the scope of the invention which, as a matter of 
language, might be said to fall therebetween.