GB2602000A

GB2602000A - Improvements in and relating to electrical testing

Info

Publication number: GB2602000A
Application number: GB2019479.1A
Authority: GB
Inventors: James Cook Austin; Philip Griffiths Alexander
Original assignee: BAE Systems PLC
Current assignee: BAE Systems PLC
Priority date: 2020-12-10
Filing date: 2020-12-10
Publication date: 2022-06-22
Anticipated expiration: 2040-12-10
Also published as: GB202019479D0; GB2602000B

Abstract

A test device 120 for performing electrical testing of a unit under test (UUT) (10, fig 2) comprises: a connector 121 for connecting the test device to a complementary connector on the UUT; a wireless transceiver 125, 128 to communicate with a remote master control unit (130, fig 2); an internal power source 127 and a power management module 126 to supply a voltage to one of a plurality of pins in the connector 121 and so to a particular pin in the complementary connector; and a detector, such as a digital multimeter (DMM) 123, to detect the presence or absence of a voltage on one or more other pins in the connector 121 depending on the test performed. The tests performed may be continuity tests by checking for voltage or dielectric or insulation tests by checking for the absence of voltage. The device may be inductively rechargeable. An adaptor may be used to connect the device to different UUTs.

Description

IMPROVEMENTS IN AND RELATING TO ELECTRICAL TESTING

The present invention relates to an improved apparatus and method for performing certain electrical tests. Such tests may be performed on complex devices, such as aircraft, before such devices are certified for use. In this description, the unit under test ((JUT) is exemplified as an aircraft, but the skilled person will readily appreciate that embodiments of the invention can be employed in a variety of different ways.

Figure 1 represents a simplified prior art installation comprising a Unit Under Test (UUT) 10, connected to a controller 30 by a plurality of connecting cables, 21, each terminated with a suitable connector 20. Each connector comprises, typically, a plurality of pins, each arranged to carry a power supply or signal.

In practice, the arrangement shown in Figure 1 might include tens or even hundreds of cables 21, each terminated at the controller 30 and the UUT 10.

Simply keeping track of the various cables and connections and ensuring that the connectors and cables are undamaged and operational is problematic.

The types of electrical test performed in such a system vary but can be split into three broad categories, including continuity tests, insulation tests and dielectric tests.

Continuity tests are performed to ensure that some or all of the pins in a specific connector are connected correctly and carry a signal as required. To do this a stimulus (e.g. 28V) is sent to each pin under test in sequence and the corresponding pin at the other end of the cable 21 is monitored to ensure that the signal is received. Further, as well as checking on an expected signal at a particular pin, a check is made on other pins to check if an unexpected signal is received, which may indicate a problem. A simple pass/fail is recorded for each such pin tested.

Insulation tests are performed to ensure that the insulation is operating correctly between pins in the same connector. In such a test, a short-duration, higher-voltage signal (e.g. 1500V is applied for a few milliseconds) is applied and -2 -other pins in the connector are monitored to ensure that no signal is detected at them in response to the stimulus.

The final category of test is an aggressive test which is typically not performed as part of commissioning, since it can result in the destruction of the connector in question. As such, it is more likely to be used during design proving of the connector, rather than in a UUT which is then to be used operationally. However, embodiments of the present invention also aim to deal with dielectric testing whereby a long-duration, higher-voltage signal (e.g. 1500V for 3 seconds) is applied and other pins are monitored. If a signal is detected on other pins, then to this may indicate that the dielectric has failed.

As mentioned above, physically connecting, checking and managing the cables 21 in the prior art is a problem. Additionally, each test installation is likely to be different, requiring new cables 21 to be prepared for each UUT, with said cables being unusable on a different UUT in the future.

It is an aim of embodiments of the present invention to address these and other shortcomings in the prior art, whether mentioned herein or not.

According to the present invention there is provided an apparatus and method as set forth in the appended claims. Other features of the invention will be apparent from the dependent claims, and the description which follows.

According to a first aspect of the present invention, there is provided a test device for performing electrical testing of a unit under test, UUT, comprising: a connector for connecting the test device to a complementary connector on the UUT; a wireless transceiver arranged to communicate with a remote master control unit; an internal power source and a power management module arranged to supply a voltage to one of a plurality of pins in the connector and so to a particular pin in the complementary connector; a detector, DMM, to detect the presence or absence of a voltage on one or more of others of the plurality of pins in the connector depending upon a test being performed.

Preferably, in the event of a continuity test being performed, the detector is operable to detect the presence of a voltage on a specified pin of the connector and in the event of an insulation or dielectric test being performed, the detector -3 -is operable to detect the absence of a voltage on the one or more of others of the plurality of pins in the connector.

Preferably, the wireless transceiver is a 5G wireless transceiver.

Preferably, the test device is provided with an RFID having a unique identity.

Preferably, if the test being performed is an insulation or dielectric test, the test device is operable to produce a relatively high voltage by stepping up a relatively low voltage supplied from the internal power source.

Preferably, there is further provided an inductive charger for recharging the internal power source.

Preferably, there is further provided an adaptor for adapting the connector to another connector having a different configuration.

According to a second aspect of the present invention, there is provided a storage and charging station arranged to receive a plurality of test devices 15 according to the first aspect and to charge the internal power source of each of the plurality of test devices.

According to a third aspect of the present invention, there is provided master control unit operable to communicate with the wireless transceiver of the test device of the first aspect and to instruct the test device to perform a certain electrical test and to receive a result from the certain electrical test.

According to a fourth aspect of the present invention, there is provided a test system comprising the master control unit of the third aspect together with at least one test device according to the first aspect.

For a better understanding of the invention, and to show how embodiments 25 of the same may be carried into effect, reference will now be made, by way of example, to the accompanying diagrammatic drawings in which: Figure 1 shows a prior art electrical testing arrangement; Figure 2 shows an electrical testing arrangement according to an embodiment of the present invention; -4 -Figures 3 and 4 show an electrical test device according to an embodiment of the present invention; Figure 5 shows a schematic representation of certain functions of the device according to an embodiment of the present invention; Figure 6 shows a storage and charging apparatus according to another embodiment of the present invention; and Figure 7 shows an electrical test device according to another embodiment of the present invention.

Figure 2 shows a representation of an embodiment of the present o invention, comprising a master control unit 130 and a plurality of wirelessly connected test devices 120 which are arranged to couple to the UUT 10. In effect, the cables 21 have been removed and a wireless connection has been introduced in place of each of them. However, this simplistic view does not represent all of the details of embodiments of the invention, nor does it represent the various issues which have been overcome.

Figures 3 and 4 show side and perspective views, respectively, of the test device 120. At one end of the device 120 is a connector 121 comprising a plurality of pins or individual connection points. The layout and configuration of the connector 121 is designed to complement a mating connector in the UUT 10.

The test device 120 is preferably arranged to have a brightly coloured exterior so as to minimise the risk of FOD -Foreign Object Debris -should it be inadvertently left behind in the UUT.

In a typical UUT 10, such as an aircraft or an assembly thereof, the connector 121 may comprise many pins and each one in the UUT will correspond with one in the connector 121 of the test device 120. Some pins may carry power and some may carry signals, but there is a 1:1 correspondence between pins in the UUT 10 and pins in the test device 120. In a typical connector for use in an aircraft, the maximum number of pins may be 128.

In the prior art, shown in Figure 1, each cable must be connected between a particular connector in the UUT and the controller 30. Ensuring that each -5 -connection is made correctly and that the cable remains free from physical damage is time consuming and prone to error. Using an embodiment of the present invention, each test device has a unique identity and the user is prompted, in each case, where a particular test device 120 is connected to a particular connector on the UUT 10. Since each test device is unique and the user is guided where each test device should go, the possibility of error is much reduced and there is no cable to become damaged or entangled.

Figure 5 shows a schematic of certain internal functional blocks of the test device 120. This will assist in understanding the operation of the test device.

At the heart of the test device 120 is controller 125, which may take the form of a suitably programmed microprocessor. This may be an off the shelf controller or it may be a custom device, incorporating certain hardware capabilities. In any event, the controller 125 includes the capability to support and operate a Fifth Generation, 5G, transmission capability. As such, each test device 120 is effectively a User Equipment, UE, as known in the art.

The use of 5G wireless technology is preferred over other possible techniques for a number of reasons. 5G is able to support a relatively high density of UEs in a given area (up to 1 million per square kilometre) without mutual interference posing a problem. The interference resistance built into the 5G standard means that no or little extra work is involved in building a robust network of UEs. Further, 5G offers a very low latency (in the range of 1-10ms), making it suitable for a fast-paced test environment. The use of Ultra-reliable Low-latency communication, URLLC, is of particular use in embodiments of the invention, where, a time lag between transmission and reception of a test could create false failures.

The controller 125 is operably coupled to an internal battery 127 via a power management module 126. The internal battery 127 is typically a high capacity cell using Lithium-ion devices, known in the art. The power management module 126 operates to regulate the power provided to the controller 125, as well as controlling the recharge operation by which the battery 127 is recharged. It further operates to control the generation of voltages used during operation to -6 -test the UUT 10. These tests were referred to previously and include a range of different voltages.

The battery 127 is arranged to have a suitable capacity to run a certain number of tests, perhaps run over several hours or even days. There is a desire 5 not to have to remove test devices only for charging purposes and so the capacity is specified accordingly.

The controller 125 is further operably coupled to at least one antenna 128. The at least one antenna comprises a 5G antenna, by which signals from the test device 120 can be transmitted to and received from the master control unit 130.

Together, the controller 125 and associated 5G antenna can be considered as a 5G transceiver.

The at least one antenna also comprises an RF ID antenna, which serves to give the test device 120 an identity which can be checked by simply holding the test device close to a suitable reader, using known RFID techniques.

The test device 120 comprises a connector, configured to mate with a corresponding connector in the (JUT 10. Each pin in the connector 121 is connectable to a voltage source whereby a test voltage can be applied. The test voltage, as mentioned previously, can be a relatively low or high voltage, applied for a relatively short or long period, as required and depending upon the exact test being performed.

The connection of a particular pin to a particular voltage is controlled by the controller 125, which is in operable communication with a digital 10 controller 124, which controls the connection status of individual pins in the connector 121. When a voltage is applied to a particular pin in a continuity test, it is necessary to check one or more other pins to ensure that a signal is received, as well as checking that no signal is received at pins not expecting one. This is carried out in the Digital Multimeter, DMM, 123, which is able to detect a signal as required. In summary, the Digital 10 module 124 controls which pins are to act as inputs and which are to act as outputs, and voltages are transmitted or received, as required, and the results detected by DMM 123 and conveyed to the controller for onward transmission to master control unit 130. -7 -

Further, there are provided a plurality of relays 122 each connected to a particular pin, as required. The relays 122 are used, in particular, when a high voltage is applied to a pin. However, the relays need not be electromechanical devices and solid state techniques may be used instead. They provide good isolation between on and off states for a particular pin.

The high voltages required for insulation and dielectric tests are generated by the power management module 126 from the battery 127. The low voltage of the battery 127 is stepped up to the required level by means of an oscillator with a capacitor/diode ladder, as known in the art.

The device controller 125 controls the operation of the test device 120 but is ultimately controlled by master control unit 130 which is able to communicate with a plurality of test devices 120, each of which is connected to a connector in the UUT 10. The master control unit 130 collects results from each test device and is able to record them and, by means of a suitably programmed computer, display them to a user, who can verify whether the UUT has passed or failed the test. If a failure is recoded, the particular pin in a particular connector can be easily identified and the test may be re-run and/or remedial work can be performed.

Figure 6 shows a storage and charging station 140 arranged to receive a plurality of test devices, when not in use. The test devices are placed individually in one of the apertures 141 provided. The station 140 can be arranged in different ways as required. In a first arrangement, the test device is inserted such that connector 121 is inserted first and charging is performed via pins in the connector 121 which couple with pins provided in the station 120. However, this requires more careful insertion and alignment, which can be time consuming.

In a preferred alternative arrangement, the test devices are inserted such that connector 121 is uppermost. Charging is performed in an inductive manner, such as is commonly used to charge electric toothbrushes and the like. No physical electrical connection is required, which means that no particular alignment is required, and the test devices can simply be dropped into the apertures 140 for storage and charging. -8 -

The storage station is preferably mains powered and may include an indicator per aperture 141 showing the charge status of the associated test device (e.g. an LED showing green for fully charged, red for charging). In this way, a user can select a test device in a fully charged state.

Figure 7 shows a test device 120 provided with a connection adaptor 140 arranged to be coupled to connector 121. In a typical UUT 10, there may be multiple connector types used. Providing different test devices 120 so that each connection type is catered for may be prohibitive and could result in keeping a very large number of variants of test device to ensure that each connection type is provided for in a particular UUT. Instead, by means of an adaptor 140, a generic test device 120 can be provided and connection to a particular connector in the UUT can be achieved by means of a suitable adaptor. Provided that sufficient pins are provided in the generic test device 120, then an adaptor can be provided to cater for any type of connector, regardless of its configuration.

The presence of the RFID tag in each device allows each test device 120 to be uniquely identified, whilst not being in an operational mode. As mentioned previously, a user is guided as to where each device should be placed in the UUT 10. One way to achieve this is by means of a portable computing device having RFID capabilities, where the user is prompted to pick a test device from the storage station 140, hold it near the computing device, which recognises its unique identity. The user is then guided to the UUT 10 and informed where to connect it. The portable computing device then knows where each device 120 is connected and this information can be used when running the test(s) later. The portable computing device is further operable to communicate with the master control unit 130 so that it is in possession of all the information about which test device is connected where and what the result(s) of the test(s) are in relation to a particular test device 120.

By means of an embodiment of the invention, it is possible to greatly improve the setup of electrical testing of a UUT by avoiding the need for complex 30 and cumbersome wiring assemblies. Embodiments of the present invention allow a much speedier, more reliable installation, where control and mapping of -9 -individual test devices to particular connectors on the UUT is coordinated and logged automatically.

Attention is directed to all papers and documents which are filed concurrently with or previous to this specification in connection with this application and which are open to public inspection with this specification, and the contents of all such papers and documents are incorporated herein by reference.

All of the features disclosed in this specification (including any accompanying claims, abstract and drawings), and/or all of the steps of any o method or process so disclosed, may be combined in any combination, except combinations where at least some of such features and/or steps are mutually exclusive Each feature disclosed in this specification (including any accompanying claims, abstract and drawings) may be replaced by alternative features serving the same, equivalent or similar purpose, unless expressly stated otherwise. Thus, unless expressly stated otherwise, each feature disclosed is one example only of a generic series of equivalent or similar features.

The invention is not restricted to the details of the foregoing embodiment(s). The invention extends to any novel one, or any novel combination, of the features disclosed in this specification (including any accompanying claims, abstract and drawings), or to any novel one, or any novel combination, of the steps of any method or process so disclosed.

Claims

-10 -CLAIMS1. A test device (120) for performing electrical testing of a unit under test, UUT (10), comprising: a connector (121) for connecting the test device to a complementary connector on the UUT; a wireless transceiver (125, 128) arranged to communicate with a remote master control unit (130); an internal power source (127) and a power management module (126) arranged to supply a voltage to one of a plurality of pins in the connector (121) and so to a particular pin in the complementary connector; a detector, DMM (123), to detect the presence or absence of a voltage on one or more of others of the plurality of pins in the connector (121) depending upon a test being performed.
2. The test device (120) of claim 1 wherein in the event of a continuity test being performed, the detector (123) is operable to detect the presence of a voltage on a specified pin of the connector (121) and in the event of an insulation or dielectric test being performed, the detector is operable to detect the absence of a voltage on the one or more of others of the plurality of pins in the connector (121).
3. The test device of claim 1 or 2 wherein the wireless transceiver is a 5G wireless transceiver.
4. The test device of any preceding claim wherein the test device is provided with an RFID having a unique identity.
5. The test device of any of claims 2 to 4 wherein if the test being performed is an insulation or dielectric test, the test device is operable to produce a relatively high voltage by stepping up a relatively low voltage supplied from the internal power source (127).
6. The test device of any preceding claim further comprising an inductive charger for recharging the internal power source (127).
7. The test device of any preceding claim further comprising an adaptor (140) for adapting the connector to another connector having a different configuration.
8 A storage and charging station (140) arranged to receive a plurality of test devices (120) according to any preceding claim and to charge the internal power source (127) of each of the plurality of test devices.
9. A master control unit (130) operable to communicate with the wireless transceiver of the test device (120) of any of claims 1 to 7 and to instruct the test device to perform a certain electrical test and to receive a result from the certain electrical test.
10. A test system comprising the master control unit of claim 9 together with at least one test device according to any one of claims 1 to 7.