4
are also interface requirements for integration into the data
processing system. All sensors require an analog or digital
interface that can be evaluated by an electronic data pro-
cessing system. The sensors should be read out synchro-
nously with a standardized time stamp.
Different values should be recorded to determine the
drilling success and the wear of the drill heads. While
some values must be measured absolutely, such as the drill-
ing progress, a relative measurement according to current
standards is for example sufficient for wear determination.
Table 1 lists the sensors that are used for monitoring. In
addition to the sensor, the table also contains the measured
values that are determined and calculated from it.
The first sensor is the displacement transducer. The goal
is to calculate the length of the borehole and the speed of
drilling. A magnetostrictive transducer is used to measure
the position of the rotation unit. The sensor is mounted
on the side of the drill feed boom. The sensor is shown in
Figure 1.
Knowing the position of the rotary unit is not enough
to calculate the hole length. The working range of the rota-
tion unit is approximately one meter. However, the hole
can be up to 100 meters long. The calculation requires the
number of drill rods installed. A calculation using only
the drill rods is too inaccurate for this application. The
measurement system adds up all the movements that the
rotation unit makes together with the drill rods. The drill
operator can press a button to tell the measurement system
whether the rotation unit is moving together with the drill
rods, or whether the drill rods are locked and the rotation
unit is working independently. This is a simple operation
and an accurate borehole length is calculated.
The second type of sensors are accelerometers. The
acceleration is measured in all 3 directions (X, Y, Z) to
identify the vibrations of the drill rig. The sensors are
directly installed at the rotation unit. This installation helps
to identify the vibrations directly from the drill rods, which
is the one place where the drill rods are directly connected.
All vibrations from the drilling and the drill bit are directly
measured. In the first phase a sensor with a high range of
±150 g is used to measure the acceleration. High vibrations
are expected from the drill bit and the rock interaction. The
sensors are shown in Figure 2.
The third set of sensors are the hydraulic pressure sen-
sors. Two sensors are used to measure the hydraulic pres-
sure at the rotation unit and at the bar holder/chuck. The
sensor on the hydraulic circuit of the rotation unit is used
to obtain a correlation between the rotation speed and the
pressure in the hydraulic circuit required for it. The sen-
sor in the hydraulic circuit of the rod holder is used to get
information about the pressure with which the drill bit is
being pushed through the rock. There is also a dependency
between the contact pressure on the rock and the speed of
the drill bit. This correlation is important for determining
whether the rock or ore is being drilled. The sensors are
installed directly on the drill rig control unit and are shown
in Figure 3.
Table 1. Description and application of the sensors to be used
Sensor Type Sensor
Measurement
Output Data
Data
Explanation
Displacement
transducer
WayCon
MAZ-
S-F-1250
Displacement
of the rotation
unit
Length and
speed of the
drilling
Accelerometer
(in all 3 axes)
Ifm
VSA205
Acceleration of
the drilling rig
Vibration of
the drilling rig
Hydraulic
pressure sensor
Ifm
PT501E
Hydraulic
pressure at the
rotation unit
Correlation
to speed
difference and
drilling force
Hydraulic
pressure sensor
Ifm
PT501E
Hydraulic
pressure at the
bar holder
Force from the
bar holder/drill
bit to the rock
Hydraulic
temperature
sensor
Ifm
TM4101
Temperature
at hydraulic
circuit
Temperature
at hydraulic
circuit
Rotational speed
sensor
Ifm
DI605A
Rotation speed
of the drill bit
Rotation speed
of the drill bit Figure 1. Sandvik DE110 with installed displacement
transducer. (Friedemann, 2024)
are also interface requirements for integration into the data
processing system. All sensors require an analog or digital
interface that can be evaluated by an electronic data pro-
cessing system. The sensors should be read out synchro-
nously with a standardized time stamp.
Different values should be recorded to determine the
drilling success and the wear of the drill heads. While
some values must be measured absolutely, such as the drill-
ing progress, a relative measurement according to current
standards is for example sufficient for wear determination.
Table 1 lists the sensors that are used for monitoring. In
addition to the sensor, the table also contains the measured
values that are determined and calculated from it.
The first sensor is the displacement transducer. The goal
is to calculate the length of the borehole and the speed of
drilling. A magnetostrictive transducer is used to measure
the position of the rotation unit. The sensor is mounted
on the side of the drill feed boom. The sensor is shown in
Figure 1.
Knowing the position of the rotary unit is not enough
to calculate the hole length. The working range of the rota-
tion unit is approximately one meter. However, the hole
can be up to 100 meters long. The calculation requires the
number of drill rods installed. A calculation using only
the drill rods is too inaccurate for this application. The
measurement system adds up all the movements that the
rotation unit makes together with the drill rods. The drill
operator can press a button to tell the measurement system
whether the rotation unit is moving together with the drill
rods, or whether the drill rods are locked and the rotation
unit is working independently. This is a simple operation
and an accurate borehole length is calculated.
The second type of sensors are accelerometers. The
acceleration is measured in all 3 directions (X, Y, Z) to
identify the vibrations of the drill rig. The sensors are
directly installed at the rotation unit. This installation helps
to identify the vibrations directly from the drill rods, which
is the one place where the drill rods are directly connected.
All vibrations from the drilling and the drill bit are directly
measured. In the first phase a sensor with a high range of
±150 g is used to measure the acceleration. High vibrations
are expected from the drill bit and the rock interaction. The
sensors are shown in Figure 2.
The third set of sensors are the hydraulic pressure sen-
sors. Two sensors are used to measure the hydraulic pres-
sure at the rotation unit and at the bar holder/chuck. The
sensor on the hydraulic circuit of the rotation unit is used
to obtain a correlation between the rotation speed and the
pressure in the hydraulic circuit required for it. The sen-
sor in the hydraulic circuit of the rod holder is used to get
information about the pressure with which the drill bit is
being pushed through the rock. There is also a dependency
between the contact pressure on the rock and the speed of
the drill bit. This correlation is important for determining
whether the rock or ore is being drilled. The sensors are
installed directly on the drill rig control unit and are shown
in Figure 3.
Table 1. Description and application of the sensors to be used
Sensor Type Sensor
Measurement
Output Data
Data
Explanation
Displacement
transducer
WayCon
MAZ-
S-F-1250
Displacement
of the rotation
unit
Length and
speed of the
drilling
Accelerometer
(in all 3 axes)
Ifm
VSA205
Acceleration of
the drilling rig
Vibration of
the drilling rig
Hydraulic
pressure sensor
Ifm
PT501E
Hydraulic
pressure at the
rotation unit
Correlation
to speed
difference and
drilling force
Hydraulic
pressure sensor
Ifm
PT501E
Hydraulic
pressure at the
bar holder
Force from the
bar holder/drill
bit to the rock
Hydraulic
temperature
sensor
Ifm
TM4101
Temperature
at hydraulic
circuit
Temperature
at hydraulic
circuit
Rotational speed
sensor
Ifm
DI605A
Rotation speed
of the drill bit
Rotation speed
of the drill bit Figure 1. Sandvik DE110 with installed displacement
transducer. (Friedemann, 2024)