Communications and Network, 2013, 5, 5-8
doi:10.4236/cn.2013.51B002 Published Online February 2013 (http://www.scirp.org/journal/cn)
Design and Realization of a Detection Program of
Conductive Slip Ring Based on LabVIEW
Lei Liu1,2, Honghai Shen1
1Key Laboratory of Airborne Optical Imaging and Measurement, Changchun Institute of Optics, Fine Mechanics and Physics,
Chinese Academy of Sciences, Changchun 130033,China
2Graduate School of the Chinese Academy of Sciences, Beijing 100039, China
Received 2012
ABSTRACT
The conductive slip ring is very useful in the industry equipments, which is an electric assembly being responsible for
transporting energy and sign als to the rotary body. In order to the conductiv e slip ring is sealing co mpletely, it’s hard to
detect that if its internal wires are conductive. The traditional manual detection is hard to finish that work when the
number of the wires is big, and a real-time detection when the equipment is rotated is impossible. This paper uses NI's
LabVIEW graphical programming software and DAQ board to realize an automatic detection system for the internal
wires of slip ring, which can help us to judge if the wires are conductive when the equipment is rotated in real-time. At
the same time, in this paper the application of LabVIEW in data acquisition is also studied.
Keywords: LabVIEW; Conductive Slip Ring; DAQ; Au tomatic Detection
1. Introduction
The conductive slip ring is an application belongs to
electrical contact sliding connection. The conductive slip
ring is also called conductive ring, slip ring or collector
ring. It can be used in any mechanical or electrical
system, which is required continuous rotation and needs
to transport power and signals from the fixed position to
the rotational positio n at the same time. The slip ring can
help to improve the performance of the system, and the
structure of the system is simplified. However, Due to
the slip ring is sealing completely, it’s hard to detect that
if its internal wires are conductive. The design in this
paper is used to detect if the internal wires of the slip ring
are connective automatically.
LabVIEW is a leading industry standard graphical
programming tools, which is mainly used for the
development of test, measurement or control system [1].
Data acquisition and instru ment contro l are both the most
competitive technology of LabVIEW [2]. Data
acquisition (DAQ) is defined the automatic process of
collecting information from the analog or digital testing
equipment such as the sensor [3]. Data acquisition system
can help us realize flexible and convenient testing or
measurement system. In this paper a design of breaking
detection system for the wires of th e conductive slip ring
is completed, which is based on the NI DAQ Board and
the graphical programming software LabVIEW [4].
2. Design Requirements
 The program should generate logic signals
automatically, an d transmit the signals to one end
of the slip ring. At the same time the signals are
collected in real time on the other end of the
conducting wires .And we can judge if the wires
are connective by the collected signals;
 The program output logic signal 1 circularly
through multiple paths in a marquee design. The
design in this paper adopts twelve routes. And the
expansion can be realized by a simple method;
 The program should realize the detection when
the equipment is working, and display the results
in a real-time. One important thing is that the
results should be easy t o obse rve.
 The program should store the collected data in a
file, which is for a further processing or
inspection.
 The program should complete the work above in
a uniform cl ock, an d a t imer is also required.
3. Design of Algorithm
*Support by the Foundation of Key Laboratory of Airborne Optical
Imaging and Measurement, Changchun Institute of Optics, Fine
Mechanics and Physics, Chinese Academy of Sciences (No.
2008AA121803, No.2009CB72400102A)
3.1. Producing Circular Logic Signal
Use the shift register, and make the logic 1 moving through

L. LIU, H. H. SHEN
6
the bits of the register. By this way the program can
generate and output logic signal 1 circularly through
multiple paths (as shown in Figure 1).
3.2. Output and Acquisition of the Signals
The output and acquisition of the signals on the ends of
the wires are the keys of this design. This design uses
NI’s DAQ board for the output and the acqu isition of the
signals (as shown in Figure 2). The output and
acquisition use sequence structure, and there should be a
certain delay between the output and the acquisition. To
ensure the collected data is right, it’s best to set th e delay
time to be the half of the cycle.
3.3. Observe the Results in Real-time
The output and collected signals are connected to some
LED lamps at the same time [5]. By this way the results
can be observe easily. If the wires are conducted, the
signal lamps on the both en ds will be lighted; however if
the wires are breaking, the lamps on the acquisition side
will not be lighted. By this way the observation in
real-time is realized (as shown in Figure 3).
Figure 1. Achieve a shift register function in LabVIEW.
Figure 2. Output and acquire the signals by DAQ board.
3.4. Save the Data to a File
The program will save the data to a file by using the
sequence structure. First it will open a file and insert a
header to the file (as shown in Figure 4); then, the data
will be saved to the file in a one-dimensional array [6].
Saving data and inserting the header need use two
different VIs (A function module in LabVIEW is called a
VI, VI is a short for Virtual instrument). The collected
logic signals cannot be saved to the file directly, so a data
type conversion is required (as shown in Figure 5). For a
further analysis of the data, the program will save an
additional data to another file, which is combined with a
data
Figure 3. Display the detection results in real time by
connecting the signals to LED lamps.
Figure 4. Save the data and Insert the header.

L. LIU, H. H. SHEN 7
that is increased bit by bit (as shown in Figure 5). The
additional data then will send to some drawing software
for further analysis [7].
3.5. Unify Clock and Time
This program use the Elapsed Time VI in the Expressed
VIs to time the whole process, and the time may obs erve
in o text box. At the same time [8], it uses the Time
Delay VI in the Expressed VIs to define the cycle of the
circulation, in order to determin e the output frequency of
the digital signals (as shown in Figure 6).
4. The Flow Chart
The flow chart is shown in Figure 7.
5. The Realization of the Design
The front panel and block diagram are shown in
Figures 8 and Figure 9.
Figure 5. Conversing data type and inserting additional
numbers.
Figure 6. Unify clock and time.
6. Test and Verification
Connect the input and output interface points and run the
program when the wires are connected and disconnected
to test if the design is reasonable [9]. We can see when
the wires are connected, all the lamps will be lighted and
the stored data are same with the output logic sig nals (as
shown in Figure 10); however, when the wires are not
connected, only the green lamps which connected to the
output signals will be lighted and all the data be saved is
zero (as shown in Figure 11). This proves that th e design
of the program is accurate [10].
In addition, the program has saved an additional data
to another file, which is combined with a data that is
increased bit by bit [11]. And then the additional data
was sent to drawing software for further analysis (The
graph in Figure 12 is drew by importing the additional
data to the software Origin, the graph can show the test
results obviously ) .
Figure 7. Flow chart.
Figure 8. Design of the front panel.

L. LIU, H. H. SHEN
8
Figure 9. Design of the block diagram. Figure 12. The graph drew in Origin.
the program can be expanded easily, which is for further
upgrading.
REFERENCES
[1] National Instruments Corporation, “Getting Started with
LabVIEW,” June 2009 Edition, Part Number
373427F-01.
[2] National Instruments Corporation, “Getting Started with
LabVIEW,” August 2007 Edition, Part Number
373427C-01.
Figure 10. The results and saved data when the wires are
connected.
[3] National Instruments Corporation, “LabVIEW User
Manual,” August 2006 Edition, Part Number
374029B-01.
[4] National Instruments Corporation, “LabVIEW Help,”
August 2006 Edition, Part Number 371361B-01.
[5] http://www.ni.com/
[6] R. Bitter, T. Mohuuddin and M. Nawrocki, “LabVIEW
Advanced Programming Techniques,” CRC Press LLC,
2001.
[7] G. W. Johnson and M. G.-Hill, “LabVIEW Power
Programming,” McGraw-Hill Companies, 1998.
Figure 11. The results and saved data when the wires are
disconnected. [8] X. H. Chen and Y. H. Zhang, “LabVIEW 8.20 Program
Design from Entry to Master,” Tsinghua University press,
2007.
7. Conclusions [9] L. Wang and M. Tao, “Be Proficient in LabVIEW,”
Publishing House of Electronics Industry, 2007.
This paper has achieved a system which is used to detect
if the slip ring is conductive. The interface is simple and
beautiful and the train of thought is clear and correct.
Also the system has the function to save the test results,
which is for further analysis. The test results prove that
the design can meet the requirements. At the same time,
[10] L. P. Yang, H. T. Li and L. Yang, “LabVIEW Program
Design and Application,” Publishing House of electronics
industry, 2005.
[11] L. P. Yang, H. T. Li and Y. Zhao, “LabVIEW Advanced
Program Design,” Tsinghua University Press, 2003.