Seed planter performance monitor

A performance monitor for a seed planting implement is disclosed herein. The monitor is preferably used with a planting system including a planting implement coupled to a tractor. The target rate at which seed is planted by the implement in the soil of an agricultural field is controlled based upon a control signal. The actual seed planting rate is monitored using an optical seed sensor supported by the implement at a location where seed exits the implement. The implement and tractor include data busses linked to each other, and signals from the seed sensors are transmitted to a controller on the tractor via the busses. The controller applies a display signal to an electronic display located in the tractor's cab to produce an image which an operator can view to determine the actual seed application rate. The image also shows the target seed application rate to allow the operator to compare actual and target rates to determine whether the implement needs to be adjusted or repaired to eliminate or reduce any deviation in rates. Seed application rates for each section of a multiple-section implement can be displayed sequentially for efficient use of the display, with the rate for each row unit also being displayed.

FIELD OF THE INVENTION 
The present invention generally relates to monitoring the actual 
performance of a selected function of an agricultural system. In 
particular, the invention relates to monitoring the actual seed planting 
rates in a planting implement and displaying the actual planting rates for 
viewing by the operator of the implement. 
BACKGROUND OF THE INVENTION 
Planting implements such as planters and drills are used for planting seed 
in agricultural fields. Planting implements include a frame having one or 
more sections. Each section supports multiple row units configured to 
apply seeds to a field as the implement is pulled across the field by an 
agricultural vehicle (e.g., a wheeled or tracked tractor). Seeds are 
stored in a seed bin mounted on or pulled behind the implement. Planters 
and drills often include additional systems for applying granular or 
liquid fertilizer, insecticide or herbicide to the field. 
Planters include meters configured to dispense or meter individual seeds to 
row units. In contrast, drills use fluted rolls to meter a mass or volume 
of seed. The metering and placement accuracy is typically higher for 
planters than drills. Seeds of crops (e.g., corn) which require relatively 
accurate metering and placement for efficient growth are typically planted 
using planters, and seeds of crop which grow efficiently in more varied 
environments (e.g., oats; wheat) are planted by less accurate and less 
expensive drills. 
Many planters and drills are made by Case Corp., the assignee of this 
invention. For example, the 955 Series EARLY RISER CYCLO AIR.RTM. Planters 
have central-fill seed bins for storing seed, pressurized air metering 
systems including cyclo seed drums for metering seed, and air distribution 
systems for delivering the metered seed to the row units. Planters in this 
series plant different numbers of rows at different row widths. For 
example, a 12/23 Solid Row Crop (SRC) Cyclo Planter plants 23 narrow rows 
or 12 wide rows when every other row unit is locked up. Drills made by 
Case Corp. include the 5300, 5400, 5500, 7100 and 7200 drills which 
include different numbers of openers, opener spacings and seeding widths. 
The 5500 Soybean Special Grain Drill, for example, includes 24 openers, 5 
inch spacings and a 30 foot width. 
Planting implements such as those described above may be equipped with 
variable-rate controllers permitting the operator to plant seed at target 
seed planting rates. Such implements may further be equipped with 
monitors, whether integral with or separate from the controllers, for 
displaying theoretical or estimated planting rates. An example of such a 
controller is available on the 955 Series Planters discussed above, and 
examples of such monitors are the Seed Flow II and Early Riser monitors 
sold by Case Corp. The seed planting rates are estimated because the 
above-described controllers and monitors do not include mechanisms or 
systems to count the seeds actually planted. Rather, the rates are 
estimated based upon known parameters such as the meter constant (i.e., 
seeds per metering drum revolution), meter rotation speed, row width and 
distance traveled. 
However, depending on the condition and adjustments of the planting 
implement, estimated seed planting rates may deviate substantially from 
the actual planting rates. For example, operator adjustments to 955 Series 
Planters which may cause errors between estimated and actual seed planting 
rates include: the pressure setting of the cyclo air metering and 
distribution systems; the setting of a seed cutoff brush which removes 
seed from seed pockets in the drum; the height of a seed chute extension 
affecting the level of seed in the drum; and the height of a leveling bar 
ensuring uniform distribution of seed across the bottom of the seed drum 
on hilly terrain. Accuracy may also be impaired by partial or total 
blockages of the tubes which deliver seeds from the drum to the row units. 
To alert the operator to conditions causing errors between the desired and 
actual seed planting rates, it would be desirable to provide a planting 
implement having a system for monitoring the actual seed planting rates by 
counting seeds actually planted, and for displaying data representative of 
such planting rates. It would also be desirable to display the performance 
monitoring data in a format easily understood by the operator for 
determining whether the implement is operating at an actual planting rate 
consistent with the desired planting rate. It would further be desirable 
to monitor and display such data for different sections or row units of an 
implement. Display of such data by section or row unit would be 
particularly desirable for variable-rate planting implements wherein 
commanded application rates vary by section or row unit. For sections 
having multiple row units, it would also be desirable to display average 
performance monitor data for the row units in each section. Based on such 
displayed data, the operator can make appropriate adjustments or repairs 
to the planting implement to minimize deviations between the actual and 
desired seed planting rates. 
SUMMARY OF THE INVENTION 
One embodiment of the invention provides a material distribution system for 
selectively applying material to the soil of an agricultural field. The 
system includes a tractor, an implement moved by the tractor across the 
field, and a metering device for metering material. The metering device 
includes a channel having an exit through which metered material passes 
before being applied. An electronic sensor generates a signal representing 
the amount of material which moves through the channel. A digital 
processing circuit monitors the material signal, determines an actual 
material application rate based upon the amount of material moved and the 
distance traveled while the material signal was monitored, and applies a 
display signal to an electronic display to generate an image representing 
the actual material application rate. 
Another embodiment of the invention provides a performance monitor system 
for a planting arrangement including an operator station such as a cab, a 
seed delivery apparatus with a target seed delivery rate controlled by a 
control signal, and a channel with an exit through which seeds move toward 
the soil. A seed sensor generates a signal representing the number of 
seeds moved through the channel. A processing circuit monitors the seed 
signal, determines an actual seed delivery rate based on the number of 
seeds moved and distance traveled while the seed signal was monitored, and 
applies a display signal to a display to generate an image representing 
the actual seed delivery rate. 
Another embodiment of the invention provides a performance monitor system 
for a planting implement with sections which each include a delivery 
apparatus with a target seed delivery rate controlled by a control signal 
and a channel to deliver seeds to a row unit. The system includes a sensor 
to generate a seed signal representing the number of seeds moving through 
the channel coupled to the sensor, a display in the operator station 
(e.g., cab) for generating images in response to display signals, and a 
processing circuit. The processing circuit monitors the seed signal from 
each sensor, determines the actual seed delivery rate for each sensor 
based upon the number of seeds and the distance traveled while each seed 
signal was monitored and applies a display signal to the display to 
generate an image for each section which represents the actual seed 
delivery rate through the seed channel of the respective section. 
Another embodiment of the invention provides a method to monitor 
performance of a planting implement. The implement includes a seed 
delivery system having a target seed delivery rate controlled by a control 
signal, and a seed channel having an exit through which seeds move toward 
the soil. The method includes applying the control signal to the seed 
delivery system to control the target seed delivery rate, sensing the 
number of seeds moving through the seed channel and generating a signal 
representative thereof, monitoring the sensed seed signal to determine an 
actual seed delivery rate based upon the number of seeds moved and the 
distance traveled while the seeds were delivered to the field, generating 
a display signal representative of the actual seed delivery rate, and 
applying the display signal to a display to generate an image representing 
the actual seed delivery rate.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS 
Referring to FIG. 1, a planting implement 10 (e.g., a 12/23 SRC Cyclo 
Planter) includes a support structure such as a frame 12, row units 14 
mounted beneath frame 12, and seed modules 16 supported by frame 12. Frame 
12 includes a middle section 18, wing sections 20 on either side of 
section 18, and a drawbar 22 extending forward from section 18. Wing 
sections 20 rotate inwardly to drawbar 22 to decrease implement width 
during transport. A hitch having an eye 24 attached to drawbar 22 connect 
to an agricultural vehicle such as a tractor (102 in FIG. 3). Twenty-three 
row units 14 are configured to plant seed in 23 rows of a field with all 
row units 14 down, or in 12 rows with every other row unit 14 locked up. 
Each module 16 meters seeds for row units 14 of one section. For example, 
the sections in FIG. 1 include 7, 8 and 8 row units 14, respectively, from 
left to right. Metered seeds are delivered through seed tubes (30 in FIG. 
2) from modules 16 to row units 14. Bins 25 storing other products (e.g., 
fertilizer, insecticide or herbicide), and metering devices therefore, are 
also supported by frame 12. Markers attached to either side 26 of frame 12 
mark the centerline of the next pass through a field. 
Referring to FIG. 2, one section of implement 10 includes eight row units 
14, a seed module 16 mounted on frame 12, and seed tubes 30 for moving 
seed from module 16 to row units 14. Seed module 16 includes a cyclo seed 
meter 32 for metering or singulating seed and to deliver the metered seed 
to row units 14. Cyclo seed meter 32 includes a perforated drum 34 secured 
by a shaft 36 to a hydraulic motor 38. The holes in drum 34 are arranged 
in circumferentially-spaced rows (e.g., 8 rows for an 8-row planter), with 
each row having a plurality of holes with diameters smaller than the seed 
being planted. The drum arrangement depends on the type of seed, and a 
line of interchangeable drums is made by Case Corp. A seed bin 40 stores 
the seed being planted. A hydraulic blower includes a hydraulic motor 42 
and a fan 44 to provide pressurized air to bin 40 and to drum 34. Seeds 
move from bin 40 to drum 34 via a seed chute (not shown) with the aid of 
higher air pressure in bin 40 than drum 34. 
During operation, blower 42-44 pressurizes drum 34 to create an air 
pressure differential above atmospheric, but lower than the air pressure 
in bin 40. As motor 38 rotates drum 34, the differential causes each hole 
to pick up one seed at the bottom of drum 34, and to retain the picked-up 
seed against the hole as drum 34 rotates. After further rotation moves the 
retained seeds above a manifold defined by openings of seed tubes 30 
adjacent to drum 34, the holes are plugged by release wheels (not shown) 
external to drum 34 to eliminate the forces which retain the seeds and 
cause the seeds to drop into tubes 30. The seeds are pushed by a cushion 
of pressurized air through seed tubes 30 to row units 14 to be planted. A 
press wheel 46 compresses the soil over the planted seed. 
The seed application rates depend upon ground speed and the rotation rate 
of drum 34. A constant application rate is obtained by driving shaft 36 
via a transmission (not shown) coupled to the implement wheels. A variable 
application rate is obtained by controlling the rotation rate of drum 34 
as a function of the ground speed (e.g., measured using implement wheel 
speed sensor 302 in FIG. 6) and a commanded application rate. A valve 
assembly (not shown) supplies pressurized hydraulic fluid to motor 38 to 
rotate shaft 36 at a variable rate in response to rate control signals 
applied to the valve assembly. 
Referring to FIG. 3, a control system 100 controls planting implement 10 
(e.g., a planter or drill) as it is pulled across a field by vehicle 102. 
Control system 100 includes electronic control units (ECUs) in 
communication with each other across a vehicle data bus 104. Vehicle data 
bus 104 includes a tractor bus segment 106 to pass data throughout vehicle 
102, and an implement bus segment 108 to communicate between vehicle 102 
and implement 10. Bidirectional data passes between busses 106 and 108 via 
a network interconnection ECU 110 (e.g., a gateway). Bus 104 preferably 
conforms to the "Recommended Practice for a Serial Control and 
Communications Vehicle Network" (SAE J-1939) which uses Controller Area 
Network (CAN) protocol for low-layer communications. ECU 110 performs 
network functions as described in the Network Layer specification of 
J-1939 by acting as a repeater for forwarding messages between segments 
106 and 108, a bridge for filtering out messages not needed by the 
receiving segment, a message router for remapping addresses and a gateway 
to repackage messages for increased efficiency. Other bus formats, 
however, may also be used and ECU 110 may perform all or only a subset of 
the above-listed network functions. 
Other ECUs coupled to tractor bus 106 include an armrest control unit (ARU) 
112, instrument cluster unit (ICU) 114, auxiliary valve control unit (AUX) 
116, electronic draft control unit (EDC) 118, transmission control unit 
(TCU) 120, power take-off control unit (PTO) 122, and engine governor 
control unit (GOV) 124. ICU 114 receives signals from a true ground speed 
sensor 126 (e.g., a radar) mounted to the body of vehicle 102. Ground 
speed sensor 126 (e.g., a radar) may also be in direct communication with 
a cab-mounted display unit (CDU) 140. A service tool 130 can be coupled to 
busses 106 and 108 via a diagnostic connector 132 for use during 
diagnostics and maintenance. 
The ECUs coupled to tractor bus 106 are illustrative and other control 
units such as a tractor performance monitor control unit or steering 
control unit could also be connected to bus 106. Further, the use of 
gateway 110 for communications between busses 106 and 108 allows a higher 
level of integration in tractors equipped with a tractor data bus. 
However, implement bus 108 and its associated ECUs may also be used to 
control implements pulled by other tractors which have no tractor data 
bus. 
Implement bus 108 includes first and second segments 134 and 136 coupled 
via a connector 138 at the rear of vehicle 102. Segment 134 passes through 
vehicle 102 and segment 136 provides a communication pathway to implement 
10. Thus, implement bus 108 reduces wiring needs between implement 10 and 
vehicle 102. Besides gateway ECU 110, ECUs coupled to segment 134 include 
cab-mounted display unit (CDU) 140. CDU 140 provides an operator 
interface, a serial interface (e.g., RS-232) to receive positioning 
signals from a DGPS receiver 142, and an interface for a memory card 144 
(e.g., a PCMCIA card). Receiver 142 receives GPS and DGPS signals from 
antennas 146 and 148. Memory card 144 transfers geo-referenced map data 
(e.g., prescription and application rate maps defined by GIS or Global 
Information System databases) between control system 100 and an external 
computer 150. Prescription maps include application rate commands, and 
application rate maps record actual (i.e., sensed) application rates. 
ECUs coupled to segment 136 of implement bus 108 are mounted to frame 12 of 
implement 10. These ECUs include a monitor interface unit (MIU) 152 and 
one or more multichannel control units (MCCs) 154. Each implement section 
typically includes one "local" MCC 154 to control product application 
rates. MIU 152 monitors application rates of products (e.g., seeds) to 
rows and other parameters (e.g., bin level, ground speed, wheel speed, 
meter pressure) based on signals generated by monitoring sensors 156, 
implement status devices 158 and a wheel speed sensor 128 (e.g., 
inductance magnetic pickup sensor) coupled to the vehicle's wheels. MIU 
152 also receives global commands from CDU 140 via bus 108, generates 
global control signals using the global commands, and applies the global 
control signals to global output devices 160 to perform global implement 
functions (e.g., lighting, frame, marker control). MCCs 154 receive local 
product application rate commands from CDU 140 based on signals generated 
by application sensors 161, generate local control signals for local 
product metering devices 162, and apply the local control signals to 
metering devices 162. Further, MCCs 154 may generate control signals for a 
variety or type switch 164 which selects the variety or type of farming 
inputs applied. MCCs 154 may also generate control signals for a section 
control switch 165 which selects which sections are enabled or disabled. 
Referring to FIG. 4, CDU 140 is an ECU mounted in the cab of vehicle 102. 
CDU 140 includes a display unit 200 including a touch screen 202 (e.g., a 
TFT 10.4" color display with digital touch screen), system touch screen 
switches 204, reconfigurable touch screen switches 206 and system reset 
switch 208. A 1/2 VGA monochrome DMTN display with LED backlighting could 
also be used. CDU 140 has interfaces 210-224 for implement bus 108, a 
remote keypad 226, DGPS receiver 142, digital inputs (e.g., an in-cab 
remote switch 228), frequency inputs such as radar 126, memory card 144 
and tractor bus 106. CDU 140 includes an audible alarm 230. A processor 
(e.g., ARM LH74610 RISC processor) coupled to memory circuits (e.g., RAM, 
EEPROM, Flash EPROM) provides control for CDU 140. 
Control system 100 can control different planting implement applications. 
An operator uses touch screen 202 to navigate and perform common functions 
within each application. System touch screen switches 204 include a MODE 
switch for toggling between applications, a CALIBRATE switch for 
performing configuration and calibration functions, and a UTILITY switch 
for performing file transfers on card 144. Touch screen switches 206 
select between items on reconfigurable menus to control the operations of 
control system 100. Reset switch 208 resets control system 100. Remote 
keypad 226, mounted via a cable near the operator when CDU 140 is mounted 
elsewhere in the cab, duplicates touch screen switches 206. In-cab remote 
switch 228 allows the operator to remotely start and stop product 
metering. Alarm 230 is used to alert the operator to error and alarm 
conditions. 
Both global and local operations of implement 10 are controlled by 
actuations of touch screen switches 204-206. The global functions include 
lighting control (e.g., turning on and off lights attached to frame 12), 
frame control (e.g., raising and lowering frame 12; folding and unfolding 
wings 20) and marker control (e.g., alternately raising and lowering 
markers attached to both sides 26 of frame 12 to mark the centerline of 
the next pass). Actuations needed to control the global functions depend 
on the particular implement. When switch actuations relate to lighting, 
frame or marker control, CDU 140 generates global command signals which 
are communicated to MIU 152 via bus 108 for controlling global output 
devices 160. 
The local implement functions include variable-rate application of products 
to a field. Touch screen switches 204-206 are actuated to control the 
rates in a manual or an automatic mode. In manual mode, the actuations 
set, increase or decrease the desired application rates for one or more 
products applied by each section. In automatic mode, the actuations select 
between one or more prescription maps stored on card 144. The maps include 
geo-referenced data representing desired application rates of one or more 
products at positions throughout a field. Desired rates are determined, 
for example, off-line using computer 150. The selected maps are indexed 
using positioning signals received by DGPS receiver 142 to determine the 
desired application rates which are then used to generate local product 
rate commands transmitted to MCCs 154. 
Referring to FIG. 5, MIU 152 is an ECU supported on frame 12 which includes 
interfaces 250-262 for implement bus 108, frame/marker outputs 264 (e.g., 
markers; wings 20), lighting outputs 266, frequency inputs 268, digital 
inputs 270, analog inputs 272 and sensor bus 274. MIU 152 is connected in 
control system 100 as shown below. Sensor bus 274 is coupled to seed rate 
sensors 276, a blockage module 278 coupled to blockage sensors 280, and a 
gateway module 282. Optical seed rate sensors 276 detect seeds passing 
through seed tubes 30 to row units 14. Module 282 receives signals from 
optical bin level sensors 284, a meter speed sensor 286, and a bin 
pressure sensor 288. Signals from bin level sensors 284 indicate when bins 
40 of modules 16 are 75% full, 50% full, 25% full, and Empty. Sensor bus 
274 is preferably an RS-485 network as described in U.S. Pat. No. 
5,635,911, herein incorporated by reference. MIU 152 is controlled by a 
processor (e.g., an AN80C196CB) coupled to memory (e.g., RAM, EEPROM, 
Flash EPROM). 
Control system 100 is a modular application control system which can be 
upgraded with additional controllers for expanded functionality. 
Initially, control system 100 includes CDU 140, implement bus 108 and MIU 
152 which provide monitoring and global control functions. In the initial 
system, product application rates are controlled conventionally (e.g., by 
driving product metering devices using gears coupled to the implement 
wheels). FIGS. 6-7 show control system 100 in embodiments which provide 
for monitoring and global control functions for implements. Control system 
100, however, can later be upgraded with MCCs 154 to provide variable-rate 
control. FIGS. 9-10 show upgraded control system 100 for the same 
implements. 
Referring to FIG. 6, control system 100 controls a 12/23 SRC Cyclo Planter 
implement 10 which includes three sections 300, each supporting multiple 
(e.g., 7, 8 and 8) row units 14 configured to apply seeds to a field. 
Seeds are metered by a seed module 16 on each section 300. MIU 152 
receives global command signals via bus 108 from CDU 140, and transmits 
back monitored data. MIU 152 receives speed signals used to calculate 
seeding data (e.g., area seeded) from a speed sensor 302 coupled to the 
planter's wheels. MIU 152 also receives signals indicating whether 
implement 10 is up or down from a status sensor 304. The application of 
products is disabled when implement 10 is raised, and is enabled with 
implement 10 down and ground speed above a predetermined value (e.g., 0.22 
m/sec). 
Sensor bus 274 is connected to a seed rate sensor 276 associated with each 
row unit 14. MIU 152 monitors seed application rates using signals 
received from seed rate sensors 276, and sends seed rate data to CDU 140 
via bus 108. Bus 274 is also coupled to a gateway module 282 on each 
section 300 to monitor the status of each seed module 16 using signals 
received from bin level sensors 284, meter speed sensor 286, and bin 
pressure sensor 288. MIU 152 transmits meter status to CDU 140. Connectors 
separate MIU 152, sensors 276 and gateway modules 282. 
Referring to FIG. 7, another embodiment of control system 100 is configured 
to control a conventional 5500 Soybean Special grain drill including two 
sections 300. Each section 300 supports multiple (e.g., 12 and 12) row 
units 14 configured to apply seeds to a field. Seeds are metered by a seed 
module 16 on each section 300. MIU 152 receives global command signals 
from CDU 140, and returns monitored data. MIU 152 also receives speed 
signals used to calculate seeding data from sensor 302 coupled to the 
drill's wheels, and receives signals indicating whether implement 10 is up 
or down from sensor 304. Application of products is disabled when 
implement 10 is raised. 
Sensor bus 274 connects to a seed rate sensor 276 associated with each row 
unit 14. MIU 152 monitors seed application rates using signals received 
from sensors 276, and sends seed rate data to CDU 140. Bus 274 is also 
coupled to bin level gateway modules 305 which monitor and receive bin 
level signals from bin level sensors 284 on each section 300. Bin status 
data is transmitted to CDU 140 and connectors separate MIU 152 and sensors 
276 and 284. 
Control system 100 may be upgraded by installing a removable MCC 154 on 
each frame section 300 to provide local variable-rate control. Referring 
to FIG. 8, each MCC 154 includes interfaces 400-410 for implement bus 108, 
on/off outputs 412 for driving valves, PWM outputs 414 for driving local 
product metering devices such as cyclo seed meter 32, frequency inputs 
416, digital inputs 418, and analog inputs 420. Connections between MCC 
154 and control system 100 are shown below. A processor (e.g., an 
AN80C196CB) coupled to memory circuits (e.g., RAM, EEPROM, Flash EPROM) 
provides control for MCC 154. 
Referring to FIG. 9, another embodiment of control system 100 further 
provides variable-rate control of the Cyclo Planter. In contrast to FIG. 
6, MCCs 154 control the seed application rates of each section 300 based 
on rate command signals received from CDU 140 via bus 108. Each MCC 154 
converts the rate command signals into PWM control signals which are 
applied to a cyclo seed meter 32 (i.e., drum) on seed module 16 (e.g., the 
PWM control signals are applied to a hydraulic valve assembly which 
regulates the flow of hydraulic fluid to motor 38). MCC 154 receives meter 
feedback speed signals from seed meter 32, and communicates the meter 
speed feedback data back to CDU 140 for display. MCC 154 could also use 
the meter speed feedback signals for closed-loop metering control. 5 Each 
MCC 154 also applies control signals to bin pressure or material flow 
sensor 288, receives pressure feedback signals from sensor 288, and 
communicates bin pressure data back to CDU 140 for display. 
Referring to FIG. 10, another embodiment of control system 100 further 
provides variable-rate control of the conventional drill. In contrast to 
FIG. 7, MCCs 154 control the rates at which seeds are applied by sections 
300 using seed rate command signals received from CDU 140. Each MCC 154 
converts the rate command signals into rate control signals which are 
applied to a seed meter 32 on each seed module 16. MCCs 154 receive 
feedback speed signals from meter 32, and communicate meter speed data 
back to CDU 140 for display. MCCs 154 can also use the speed feedback 
signals for closed-loop metering control. 
Referring to FIGS. 11a-11c, control system 100 monitors the actual 
performance of implement 10 and shows actual performance data to the 
operator on display 202 of CDU 140. To efficiently use the display, 
performance data for each section 300 of implement 10 is displayed 
sequentially. The location of the section 300 for which data is currently 
being displayed is labeled at reference numeral 500. For example, FIGS. 
11a, 11b and 11c display performance data for the left, center and right 
sections 300, respectively, of the Cyclo Planter of FIGS. 6 and 9. The CDU 
screens for the drill of FIGS. 7 and 10 sequence between left and right 
sections 300. The performance of implement 10 is scanned by showing data 
for each section 300 for a predetermined time period (e.g., 2 sec) before 
showing data for the next section 300. The sections are continually 
scanned. However, a touch screen scan switch 502 allows the operator to 
pause the scan procedure on a selected section 300, and to resume 
scanning. A second touch screen switch 504 is used to display seed 
spacing. 
The displayed data includes the implement type 506 (e.g., "12/23 Cyclo"), 
product type 508 (e.g., "A" for product stored in bin A; "B" for product 
in bin B, etc.), section average rate 510 (e.g., average delivery rate of 
29,100 s/acre across row units 14 of the left section), display 
identification 512 (e.g., "Rate"), implement speed 514 (e.g., "5.2 mph"), 
bin pressure 516 (e.g., "9.8 oz/si"), bin pressure controls 518 (e.g., 
"OFF", "+" and "-"), bin level 520, menu bar 522 and bar graph 524. 
Implement type 506 may differ since control system 100 can be programmed 
for use with different implement types. Implement speed 514 is determined 
using signals from wheel speed sensor 302 (or radar 126). Bin pressure 
controls 518 provide control over air pressure in module 16. Bin level 520 
displays the height of product in one or more bins 40. Alarm 230 alerts 
the operator when the lowest bin level is reached. Menu bar 522 allows the 
operator to select the CDU mode, and includes a "MONITOR" touch-screen 
switch to select performance monitoring. 
Based upon the sensed signals, control system 100 calculates and displays 
performance monitor data such as planting rate (Seed.sub.-- Rate), seed 
spacing (Seed.sub.-- Spacing), seed metering performance (Seed.sub.-- 
Meter.sub.-- Perf), percent singles metered (%.sub.-- Singles.sub.-- 
Metered), and accumulated metering performance (Accumulated.sub.-- 
Meter.sub.-- Perf). For each data item, CDU 140 displays a section average 
and a bar graph visually representing data for each row unit 14. 
Planting rate is defined as the actual amount of product (e.g., number of 
seeds) applied over an area (hectare or acre): 
EQU Seed.sub.-- Rate=Seed.sub.-- Sensor.sub.-- Count/(Distance.sub.-- 
Traveled*Row.sub.-- Width) 
wherein Seed.sub.-- Sensor.sub.-- Count is the number of seeds counted by 
seed sensors 276, Distance.sub.-- Traveled is the product of ground speed 
(sensed by wheel speed sensor 302) and time, and Row.sub.-- Width is the 
width between row units 14. Seed spacing, displayed in response to 
actuations of switch 504, is defined as the spacing (cm or in) between 
seeds: 
EQU Seed.sub.-- Spacing=Distance.sub.-- Traveled/Seed.sub.-- Sensor.sub.-- Coun 
t 
Seed meter performance is defined as the actual seed delivery rate divided 
by a theoretical or target rate: 
EQU Seed.sub.-- Meter.sub.-- Perf=(Seed.sub.-- Rate/Target.sub.-- Seed.sub.-- 
Rate)*100 
wherein Target.sub.-- Seed.sub.-- Rate is the target seed rate based upon 
either a feedback speed signal from meter 32 (e.g., 5 sec average) and the 
arrangement of the seed drum, or upon the commanded seed planting rate. 
Percent singles metered is defined as the count from seed sensors 276 of 
metered seeds passing through seed tube 30 one at a time divided by the 
total number of seeds over an interval: 
EQU %.sub.-- Singles.sub.-- Metered=Counted.sub.-- Singles/(Target.sub.-- 
Seed.sub.-- Rate*Distance.sub.-- Traveled*Row.sub.-- Width) 
Accumulated meter performance is defined as an operator-resettable running 
average of the seed meter performance: 
EQU Accumulated.sub.-- Meter.sub.-- Perf.sub.n =(Accumulated.sub.-- 
Meter.sub.-- Perf.sub.n-1 *(n-1)+Seed.sub.-- Meter.sub.-- Perf)/n 
The seed planting rate for n row units 14 of each section 300, averaged 
over one second and five seconds, respectively, are as follows: 
EQU Value=(.SIGMA.Seed.sub.-- Rate.sub.n)/n 
EQU Section.sub.-- Average.sub.n =(Value.sub.n-4 +Value.sub.n-3 +Value.sub.n-2 
+Value.sub.n-1 +Value.sub.n)/n 
The five-second section average ("Section.sub.-- Average") is used for 
display (e.g., used for section average rate 510), except that the current 
seed rate value ("Value") is used for the accumulated meter performance. 
Bar graph 524 includes bars (e.g., bars 1-7 in FIG. 11a; bars 1-8 in FIGS. 
11b and 11c) showing the planting performance for row units 14 of each 
section 300 of the 12/23 Cyclo Planter. Five ranges along the vertical 
axis represent 85%, 90%, 95%, 100% and 105% of a target seed delivery 
rate, with 100% of the target rate marked by a horizontal line 526. The 
target rate, set manually or automatically based upon the implement 
position and a prescription map, may differ for each section 300 during 
variable-rate application. For example, the target rate is 30,000 s/acre 
for the left and right sections (FIGS. 11a and 11c), and 28,500 s/acre for 
the center section (FIG. 11b). Actual delivery rates for row units 14 are 
shown by the bars on graph 524. Row unit 1 of the left section, for 
example, has applied seed at an actual rate of 31,500 s/acre. Displaying 
the actual rate based upon the target rate normalizes the actual seed 
delivery rate. Thus, bar graph 524 is an easily understood performance 
monitor for each section and row unit of implement 10 since deviations in 
rates are represented by differences between horizontal line 526 and the 
actual rate markers. An operator noticing large deviations between actual 
and target seed rates can re-adjust or repair implement 10. 
Other application parameters calculated by control system 100, and 
displayed on CDU 140, include the total area (hectares or acres) the 
system has monitored during its lifetime, the total area monitored during 
the season, and the total area monitored in the field. The lifetime area 
counter is non-resettable, while the season area and field area counters 
are resettable by the operator. The implement performance is monitored 
during application of seed, and is enabled when the implement status 
switch 304 indicates that implement 10 is down and the ground speed 
exceeds a predetermined value (e.g., 0.22 meter/sec). 
While the embodiments illustrated in the FIGURES and described above are 
presently preferred, it should be understood that these embodiments are 
offered by way of example only. The control system disclosed herein may be 
modified for use on other planters, conventional or air drills, other 
planting implements and material spreaders having variable-rate control, 
and other electronically-controlled application implements. The invention 
is not intended to be limited to any particular embodiment, but is 
intended to extend to modifications that nevertheless fall within the 
scope of the claims.