GB2551182A

GB2551182A - Lighting devices, system, method and computer program code

Info

Publication number: GB2551182A
Application number: GB1610090.1A
Authority: GB
Inventors: Newman Peter
Original assignee: FW Thorpe PLC
Current assignee: FW Thorpe PLC
Priority date: 2016-06-09
Filing date: 2016-06-09
Publication date: 2017-12-13
Anticipated expiration: 2036-06-09
Also published as: GB201610090D0; GB2551182B

Abstract

A lighting system 100 comprises a plurality of lighting devices 10a 10ff distributed across an area and operable to illuminate the area, wherein at least some of the lighting devices each comprise: means for receiving and retransmitting a wireless colour temperature signal; and means for adjusting a colour temperature of the lighting device based on the wireless colour temperature signal. A master control unit 30 may be provided comprising a colour temperature sensor 36 configured to sense an ambient colour temperature and a wireless transceiver 38 configured to transmit wireless colour temperature signals to one or more of the lighting devices which may act as signal repeaters to retransmit the signals to other lighting devices.

Description

TITLE

Lighting devices, system, method and computer program code TECHNOLOGICAL FIELD

Embodiments of the present invention relate to a lighting system. In particular, they relate to a lighting system comprising a plurality of lighting devices with an adjustable colour temperature.

BACKGROUND

The sleep and wake cycle of a person’s body is regulated by its circadian rhythm. The colour temperature of light is thought to control a person’s circadian rhythm and can potentially affect a person’s mood. For example, a warm “red” coloured light may give a person a relaxed feeling, whereas a cooler, “blue” coloured light may give a person a more focused, work-like feeling.

BRIEF SUMMARY

According to various, but not necessarily all, embodiments of the invention there is provided a lighting system, comprising: a plurality of lighting devices distributed across an area and operable to illuminate the area, wherein at least some of the lighting devices each comprise: means for receiving and retransmitting a wireless colour temperature signal; and means for adjusting a colour temperature of the lighting device based on the wireless colour temperature signal.

The lighting system may further comprise: a master control device comprising a transmitter for transmitting wireless colour temperature signals and control means for controlling the transmitter to transmit the wireless colour temperature signals for subsequent reception and retransmission by at least some of the lighting devices.

The control means of the master control device may be configured to control the transmitter of the master control device to transmit wireless colour temperature signals at predetermined times during a day. One or more of the predetermined times may be user adjustable.

The master control device may be configured to adjust one or more of the predetermined times at which the wireless colour temperature signals are transmitted based on at least one of a sunrise time and a sunset time. The master control device may be configured to determine the sunrise time and/or the sunset time based on the geographical position of the lighting system. Intervals between the transmission of the wireless colour temperature signals depend upon at least one of a sunrise time and a sunset time. A colour temperature for at least one of the lighting devices may be specified in each wireless colour temperature signal. The specified colour temperature may depend upon at least one of a sunrise time and a sunset time.

The lighting system may further comprise at least one colour temperature sensor for sensing an ambient colour temperature. A colour temperature specified in the wireless colour temperature signals may be determined from the ambient colour temperature sensed by the at least one colour temperature sensor. The colour temperature specified in the wireless colour temperature signals may be the same as the colour temperature sensed by the at least one colour temperature sensor.

The lighting system may further comprise means for enabling a user to manually override the wireless colour temperature signals and set a colour temperature for one or more of the lighting devices.

According to various, but not necessarily all, embodiments of the invention there is provided a lighting device, comprising: a receiver for receiving a wireless colour temperature signal; control means for controlling a colour temperature of the lighting device based on the wireless colour temperature signal; and a transmitter for retransmitting the wireless colour temperature signal to at least one further lighting device.

The wireless colour temperature signal may specify a colour temperature for the lighting device. The lighting device may further comprise at least one light source configured to emit light of a first colour temperature, and at least one further light source configured to emit light of a second colour temperature, different from the first colour temperature. The control means may be configured to control emission of light from the at least one light source and the at least one further light source such that combined light emitted from the at least one light source and the at least one further light source has the colour temperature specified in the wireless colour temperature signal.

According to various, but not necessarily all, embodiments of the invention there is provided a method, comprising: receiving a wireless colour temperature signal; controlling a colour temperature of a lighting device based on the wireless colour temperature signal; and re-transmitting the wireless colour temperature signal to at least one further lighting device.

According to various, but not necessarily all, embodiments of the invention there is provided computer program code that, when executed by at least one processor, enables the above method to be performed.

According to various, but not necessarily all, embodiments of the invention there is provided a lighting system as described herein and illustrated in the appended figures.

According to various, but not necessarily all, embodiments of the invention there is provided a lighting device as described herein and illustrated in the appended figures.

According to various, but not necessarily all, embodiments of the invention there is provided examples as claimed in the appended claims.

BRIEF DESCRIPTION

For a better understanding of various examples that are useful for understanding the detailed description, reference will now be made by way of example only to the accompanying drawings in which:

Fig. 1 illustrates a schematic of a lighting device;

Fig. 2 illustrates a schematic of a master control device;

Fig. 3 illustrates a lighting system including a plurality of lighting devices, such as that illustrated in Fig. 1, and a master control unit as illustrated in Fig. 2;

Fig. 4 illustrates a flow chart of a method carried out at the master control device; and Fig. 5 illustrates a method carried out at a lighting device.

DETAILED DESCRIPTION

Embodiments of the invention relate to a lighting system comprising a plurality of lighting devices with an adjustable colour temperature. A master control device determines a colour temperature for one or more lighting devices in the lighting system and transmits a wireless colour temperature signal specifying that colour temperature. The wireless colour temperature signal is received, processed and retransmitted by at least some of the lighting devices, causing the wireless colour temperature signal to propagate throughout the lighting system.

Fig. 1 illustrates a schematic of a lighting device/luminaire 10. The lighting device 10 comprises control means 12, a first light source 16a, a second light source 16b, an ambient light sensor 17, a proximity sensor 18 and a wireless transceiver 19.

The wireless transceiver 19 is configured to transmit and receive wireless signals, such as wireless colour temperature signals. A wireless colour temperature signal may specify a colour temperature. In some implementations of the invention, a wireless colour temperature signal may specify a single colour temperature for each and every lighting device 10 in a lighting system. In other implementations, different colour temperatures may be specified in the wireless colour temperature signal for different groups of lighting devices 10 within the lighting system. This is described in further detail below.

The wireless signals that are transmitted and received by the wireless transceiver 19 may, for example, be radio frequency signals.

The ambient light sensor 17 is configured to sense ambient light and provide ambient light data, such as an illuminance reading, to the control means 12.

The proximity sensor 18 is configured to sense the presence of a body near to the lighting device 10. Such a body could, for example, be a vehicle or a human. In some implementations, the proximity sensor 18 is a motion sensor. It may, for instance, be a passive infrared (PIR) sensor.

In some embodiments, the functionality of the ambient light sensor 17 and the proximity sensor 18 may be combined into a single “intelligent” sensor 15.

The first light source 16a is configured to emit light of a first, predetermined, colour temperature. The second light source 16b is configured to emit light of a second, predetermined colour temperature. The second colour temperature is different from the first colour temperature. For example, the first colour temperature could be 3000K and the second colour temperature could be 6500K. In some embodiments, the first light source 16a comprises a plurality of light emitting devices, such as a plurality of light emitting diodes, and the second light source 16b comprises a second plurality of light emitting devices, such as a plurality of light emitting diodes.

The control means 12 is configured to receive information from the wireless transceiver 19 that has been received in a wireless signal. The control means 12 is also configured to control the wireless transceiver 19 to transmit wireless signals.

The control means 12 is configured to receive inputs from the proximity sensor 18. For example, the control means 12 may receive inputs from the proximity sensor 18 that indicate that the proximity sensor 18 has detected a body in the vicinity of the lighting device 10.

The control means 12 is configured to control the first light source 16a and the second light source 16b. For example, the control means 12 controls whether or not each of the first light source 16a and the second light source 16b emits light. The control means 12 is also configured to control the intensity of light that is emitted by each of the first light source 16a and the second light source 16b. If, for example, the control means 12 wishes to control the combined output of the first and second light sources 16a, 16b to have a particular colour temperature, it may control the intensity of light that is emitted by each light source 16a, 16b appropriately. For example, in order to achieve an overall light output that has a colour temperature which is closer to, but not the same as, the first colour temperature, the control means 12 may control the first light source 16a to output light at a higher intensity than the second light source 16b.

The control means 12 may comprise control circuitry and one or more memories. The control means 12 may be implemented in hardware alone, have certain aspects in software including firmware alone or be a combination of hardware and software (including firmware). The software and/or firmware is/are computer program code that can be stored in the one or more memories. The computer program code, when executed, controls the operation of the control circuitry.

The elements 12, 16a, 16b, 18 and 19 are operationally coupled and any number or combination of intervening elements can exist (including no intervening elements).

Fig. 2 illustrates a master control unit 30. The master control unit 30 comprises control means 32, at least one colour temperature sensor 36 and a wireless transceiver 38.

The colour temperature sensor 36 is configured to sense an ambient colour temperature. In use, the colour temperature sensor 36 may be positioned to sense the colour temperature of natural sunlight. For example, the colour temperature sensor 36 may be positioned outdoors or near a window.

The wireless transceiver 38 is configured to receive and transmit wireless signals. For example, the wireless transceiver 38 may be configured to transmit radio frequency signals. The wireless signals transmitted by the wireless transceiver 38 may be wireless colour temperature signals that specify a colour temperature at which light is to be output by one or more lighting devices.

The control means 32 is configured to receive inputs from the colour temperature sensor 36 indicating a sensed colour temperature.

The control means 32 is configured to receive information from the wireless transceiver 38 that has been received in a wireless signal. The control means 32 is also configured to control the wireless transceiver 38 to transmit wireless signals.

The control means 32 may comprise control circuitry and one or more memories. The control means 32 may be implemented in hardware alone, have certain aspects in software including firmware alone or be a combination of hardware and software (including firmware). The software and/or firmware is/are computer program code that can be stored in the one or more memories. The computer program code, when executed, controls the operation of the control circuitry.

The elements 32, 36, 38 are operationally coupled and any number or combination of intervening elements can exist (including no intervening elements).

In some implementations, the control means 12, the colour temperature sensor(s) 36 and the wireless transceiver 38 may be positioned in a single housing. In other implementations, the colour temperature sensor(s) 36 may be positioned in a different housing from the control means 32 and the wireless transceiver 38, for example.

Fig. 3 illustrates a lighting system 100 comprising the master control unit 30 and a plurality of lighting devices 10a - 10ff distributed across an area and operable to illuminate the area. In this example, the lighting devices 10a - 10ff are considered to be in separate groups. A first plurality of the lighting devices 10a - 10p is considered to be in “group 1” and a second plurality of the lighting devices 10q - 10ff is considered to be in “group 2”. The lighting devices 10a -10p in group 1 may, for instance, be in a different room or a different building from the lighting devices in group 2.

In the illustrated example, the lighting system 100 further comprises a local control device 60 that may comprise control means and a wireless transceiver. The functionality of the local control device 60 is described in further detail below.

Fig. 4 illustrates a flow chart of a method carried out at the master control device 30. Fig. 5 illustrates a method carried out at each of the lighting devices 10a -10ff.

In operation, at block 301 of Fig. 4, the control means 32 of the master control device 30 determines whether the current time is between a start time and an end time. The start time could, for example, be in the morning (e.g. 6am) and the end time could, for example, be in the late afternoon or the evening (e.g. 6pm). The control means 32 may determine the current time via an internal clock or, for instance, a connection to the internet. The start time and the end time may be user adjustable.

If the control means 12 determines that the current time is not between the start time and the end time, the method of Fig. 4 proceeds to block 302b in which the control means 32 waits for a predetermined time interval before reverting back to block 301 in which the current time is again compared with the start time and the end time.

If the current time is the between the start time and the end time, the method proceeds to block 302a in which the control means 32 determines a colour temperature. In this example, the control means 32 receives an input from the colour temperature sensor 36 which indicates the current (outdoor) ambient colour temperature. In other examples, the control means 32 does not receive an input from a colour temperature sensor 36 and, instead, it may estimate the colour temperature based upon the current time. Such an estimate could be based on local sunrise and sunset times. Local sunrise and sunset times may be user configurable. Alternatively or additionally, the control means 32 may be able to determine local sunrise and sunset times from a connection to the internet (e.g. via the wireless transceiver 38 or a different transceiver).

In some embodiments of the invention, there may be a remote server storing sunrise and sunset times for a plurality of different geographical locations. The control means 32 may be able to determine its geographical location from geographical information provided by a user via user input circuitry or a satellite positioning receiver. The master control unit 30 may send a request to the server which includes its geographical position and, in response, the server may respond with the local sunrise and sunset times for that geographical position.

After the colour temperature has been determined by the control means 32 in block 302a, the method proceeds to block 303 in Fig. 4 in which the control means 32 controls the wireless transceiver 38 to transmit a wireless colour temperature signal. The wireless colour temperature signal may specify the colour temperature that was determined in block 302a. The method then proceeds to block 304 in which the control means waits for a predetermined time interval (e.g. 5 minutes or 10 minutes) before returning to block 301 and beginning the method again. The predetermined interval may be user adjustable.

Cycling through the method in Fig. 4 causes the master control device 30 to transmit wireless colour temperature signals at predetermined times in a day.

Fig. 3 illustrates the master control device 30 transmitting wireless colour temperature signals. In the example illustrated in Fig. 3, the master control device 30 includes a colour temperature sensor 36 that is positioned outdoors or near a window, in a different housing from the control means 32 and the wireless transceiver 38 (which may, for example, be positioned indoors away from a window). The colour temperature sensor 36 may be operably connected to the control means 32 via a wired or wireless connection.

Fig. 5 illustrates a flow chart of a method carried out at each of the lighting devices 10a-10ff in Fig. 3.

In this example, one or more lighting devices that are positioned close to the master control device 30 receives the wireless colour temperature signal transmitted by the master control device 30, such as the lighting devices marked with reference numerals 10a, 10e and 10i in Fig. 3. Each of these lighting devices 10a, 10e, 10i interprets the wireless colour temperature signal transmitted by the master control device 30 and then controls/adjusts the colour temperature of the light it emits based upon the received wireless colour temperature signal. For example, the control means 12 of each of the lighting devices 10a, 10e, 10i controls its first light source 16a and/or its second light source 16b such that the light which is emitted matches the colour temperature specified in the wireless colour temperature signal.

The method then proceeds to block 503, in which the control means 12 of each of the lighting devices 10a, 10e and 10i causes its local wireless transceiver 19 to retransmit the same wireless colour temperature signal that it received from the master control device 30, effectively acting as a signal repeater. This method is repeated at each of the lighting devices 10a - 10ff, which causes the signal to propagate throughout the lighting system 100, causing the control means 12 of each of the lighting devices 10a - 10ff to control the light that is emitted by each of the lighting devices 10a - 10ff to match the colour temperature specified in the wireless colour temperature signal that was originally transmitted by the master control device 30.

In some embodiments of the invention, it is possible for the master control device 30 to control lighting devices 10a - 10ff in different groups to have different colour temperatures. In this regard, each lighting device 10a -10ff has a group identifier and the wireless colour temperature signal transmitted by the master control device 30 may also include a group identifier. When the wireless colour temperature signal is received by each of the lighting devices 10a - 10ff, the control means 12 of each of the lighting devices 10a - 10ff processes the signal to determine whether the group identifier in the signal matches its own group identifier. If so, the lighting device 10a -10ff adjusts the colour temperature of the light it emits based on the wireless colour temperature signal. If not, the lighting device 10a - 10ff does not adjust the colour temperature of the light it emits and instead merely retransmits the wireless colour temperature signal.

The lighting system 100 may comprise one or more local control devices, each of which provides means for enabling the wireless colour temperature signal transmitted by the master control device 30 to be manually overridden. In the example illustrated in Fig. 3, the lighting devices 10a - 10ff in the lighting system 100 are split into two different groups. The lighting devices 10a - 10p are in “group 1” and the lighting devices 10q - 10ff are in “group 2”. As explained above, the lighting devices 10a -10p in group 1 could be in a different room from the lighting devices 10q - 10ff in group 2, or in a different building.

In the example illustrated in Fig 3, the lighting devices 10q - 10ff in group 2 have an associated local control device 60. The local control device 60 may, for example, include user input circuitry, control means and a wireless transceiver. A user may set a particular colour temperature via the user input circuitry and, in response, the control means of the local control device 60 may cause a wireless transceiver 38 to transmit a wireless signal, specifying the colour temperature input by the user. The wireless colour temperature signal transmitted by the local control device 60 may be received initially by the lighting devices adjacent to the local control device 60, such as the lighting devices labelled with reference numerals 10dd, 10ee and 10ff in Fig. 3. The lighting devices 10dd, 10ee, 10ff then retransmit the wireless colour temperature signal which propagates throughout the lighting system in the manner described above.

In some embodiments, the colour temperature setting input by the user will then remain in place, irrespective of colour temperature commands transmitted by the master control device 30, until the area occupied by the group 2 lighting devices 10q - 10ff is vacated or the user manually returns control back to the master control device 30 by providing input at the local control device 60.

The wireless colour temperature signal transmitted by the local control device 60 may include a group identifier identifying, in this example, group 2 of the lighting devices 10q - 10ff. If a lighting device 10a - 10ff determines that its own group identifier matches that in the wireless colour temperature signal, it adjusts its colour temperature accordingly; otherwise it merely retransmits the signal.

As the master control device 30 cycles through the method of Fig. 4, it periodically transmits new wireless colour temperature signals to the lighting devices 10a - 10ff, causing them to gradually adjust their colour temperature over the course of a day.

In some embodiments, each of the wireless colour temperature signals may include a unique identifier. The control means 12 of each of the lighting devices 10a -10ff may be configured to compare an identifier in a recently received wireless colour temperature signal with the identifiers in previously received wireless colour temperature signals. If there is no match, the identifier indicates that the recently received wireless colour temperature signal has not been received before and the signal is acted upon and retransmitted. Alternatively, if there is a match, the lighting device may take no action (and not retransmit the signal).

It was mentioned above that each of the lighting devices 10a - 10ff has a proximity sensor 18. The control means 12 of each of the lighting devices 10a - 10ff may be configured to switch off the light sources 16a, 16b in each lighting device 10a 10ff unless a body is detected. If the control means 12 of a lighting device 10a - 10ff receives inputs from a proximity sensor 18 indicating that a body 50 is in the vicinity of that lighting device 10a - 10ff, such as the body 50 shown when group 1 of the lighting devices 10a - 10p in Fig. 3, the control means 12 of that lighting device 10a -10ff controls at least one of the light sources 16a, 16b to emit light and controls the wireless transceiver 19 to transmit a wireless alert signal specifying the relevant group identifier. If that wireless alert signal is received by a lighting device 10a - 10ff that has the same group identifier, the control means 12 of that lighting device 10a -10ff causes at least one of the light sources 16a, 16b to begin emitting light.

Upon reception of a wireless alert signal specifying the relevant group identifier, a lighting device 10a - 10ff may emit light for a predetermined period of time before ceasing to emit light. This means that when an area occupied by a particular group of lighting devices 10a - 10ff is vacated, the lighting devices 10a - 10ff in that group will cease to emit light after the predetermined period of time has expired. As explained above, when an area is vacated, any manual colour temperature setting may be replaced with the colour temperature set by the master control device 30. When the lighting devices 10a - 10ff in the group begin to emit light again, they emit light of a colour temperature specified by the master control device 30.

The control means 12 of each of the lighting devices 10a — 10ff may be configured to determine the colour temperature specified in a wireless colour temperature and to store the specified colour temperature irrespective of whether the lighting device 10a - 10ff is emitting light. If, for example, the colour temperature is stored while a particular lighting device 10a - 10ff is not emitting light, the control means 12 can control one or both of the light sources 16a, 16b to begin emitting light with the specified colour temperature when the light source(s) 16a, 16b is/are activated.

The control means 12 of each lighting devices 10a - 10ff may also be configured to control the combined illuminance of the light sources 16a, 16b based on readings provided by the ambient light sensor 17. For example, the control means 12 may dim the output of the light sources 16a, 16b based on such readings.

The wireless colour temperature signals and the wireless alert signals may adhere to the same wireless protocol.

In addition to the above, the control means 12 of each lighting device 10a -10ff may be configured to determine energy usage statistics and to control its wireless transceiver 19 to transmit the energy usage characteristics of that lighting device 10a - 10ff to a remote server (e.g. for review via a website). Also, the control means 32 of the master control device 30 or a remote computer may provide the user with the ability to interrogate the status and operation of each lighting device 10a, 10ff, including emergency escape lighting operation.

The blocks illustrated in Figs. 4 and 5 may represent steps in a method and/or sections of code in computer program code. The illustration of a particular order to the blocks does not necessarily imply that there is a required or preferred order for the blocks and the order and arrangement of the block may be varied. Furthermore, it may be possible for some blocks to be omitted.

Where a structural feature has been described, it may be replaced by means for performing one or more of the functions of the structural feature whether that function or those functions are explicitly or implicitly described.

Although embodiments of the present invention have been described in the preceding paragraphs with reference to various examples, it should be appreciated that modifications to the examples given can be made without departing from the scope of the invention as claimed. For example one or more of lighting devices 10a -10ff may include more than two light sources 16a, 16b.

Features described in the preceding description may be used in combinations other than the combinations explicitly described.

Although functions have been described with reference to certain features, those functions may be performable by other features whether described or not.

Although features have been described with reference to certain embodiments, those features may also be present in other embodiments whether described or not.

Whilst endeavouring in the foregoing specification to draw attention to those features of the invention believed to be of particular importance it should be understood that the applicant claims protection in respect of any patentable feature or combination of features hereinbefore referred to and/or shown in the drawings whether or not particular emphasis has been placed thereon. l/we claim:

Claims

1. A lighting system, comprising: a plurality of lighting devices distributed across an area and operable to illuminate the area, wherein at least some of the lighting devices each comprise: means for receiving and retransmitting a wireless colour temperature signal; and means for adjusting a colour temperature of the lighting device based on the wireless colour temperature signal.

2. The lighting system of claim 1, further comprising: a master control device comprising a transmitter for transmitting wireless colour temperature signals and control means for controlling the transmitter to transmit the wireless colour temperature signals for subsequent reception and retransmission by at least some of the lighting devices.

3. The lighting system of claim 2, wherein the control means of the master control device is configured to control the transmitter of the master control device to transmit wireless colour temperature signals at predetermined times during a day.

4. The lighting system of claim 3, wherein one or more of the predetermined times are user adjustable.

5. The lighting system of claim 3 or 4, wherein the master control device is configured to adjust one or more of the predetermined times at which the wireless colour temperature signals are transmitted based on at least one of a sunrise time and a sunset time.

6. The lighting system of claim 5, wherein master control device is configured to determine the sunrise time and/or the sunset time based on the geographical position of the lighting system.

7. The lighting system of claim 5 or 6, wherein intervals between the transmission of the wireless colour temperature signals depend upon at least one of a sunrise time and a sunset time.

8. The lighting system of any of claims 5 to 7, wherein a colour temperature for at least one of the lighting devices is specified in each wireless colour temperature signal, and the specified colour temperature depends upon at least one of a sunrise time and a sunset time.

9. The lighting system of any of the preceding claims, further comprising at least one colour temperature sensor for sensing an ambient colour temperature, wherein a colour temperature specified in the wireless colour temperature signals is determined from the ambient colour temperature sensed by the at least one colour temperature sensor.

10. The lighting system of claim 9, wherein the colour temperature specified in the wireless colour temperature signals is the same as the colour temperature sensed by the at least one colour temperature sensor.

11. The lighting system of any of the preceding claims, further comprising means for enabling a user to manually override the wireless colour temperature signals and set a colour temperature for one or more of the lighting devices.

12. A lighting device, comprising: a receiver for receiving a wireless colour temperature signal; control means for controlling a colour temperature of the lighting device based on the wireless colour temperature signal; and a transmitter for re-transmitting the wireless colour temperature signal to at least one further lighting device.

13. The lighting device of claim 12, wherein the wireless colour temperature signal specifies a colour temperature for the lighting device.

14. The lighting device of claim 13, further comprising at least one light source configured to emit light of a first colour temperature, and at least one further light source configured to emit light of a second colour temperature, different from the first colour temperature, wherein the control means is configured to control emission of light from the at least one light source and the at least one further light source such that combined light emitted from the at least one light source and the at least one further light source has the colour temperature specified in the wireless colour temperature signal.

15. A method, comprising: receiving a wireless colour temperature signal; controlling a colour temperature of a lighting device based on the wireless colour temperature signal; and re-transmitting the wireless colour temperature signal to at least one further lighting device.

16. Computer program code that, when executed by at least one processor, enables the method of claim 15 to be performed.

17. A lighting system as described herein and illustrated in the appended figures.

18. A lighting device as described herein and illustrated in the appended figures.