FIELD OF THE INVENTION

The invention relates to a method of providing feedback related to a user's physical state using a portable unit for carrying on the user and capable of communicating with a remote system. The invention also relates to a portable device for carrying on a user, capable of communication with a remote system.

The invention also relates to a system for processing information corresponding to at least one measurement signal representative of at least one measurement of one of: - a physiological parameter of a user of a remote portable unit for carrying on a user and a parameter associated with ambient conditions experienced by the user of the remote portable unit.

The invention also relates to a computer program.

BACKGROUND OF THE INVENTION

US 2003/0126593 discloses a system to assist a person to monitor a physiological parameter, comprising: a monitor module comprising a transducer providing physiological data correlated with the physiological parameter; an interactive television system; a remote computer system; and a software application program on the interactive television receiver, adapted to process physiological data, to transmit the physiological data over a communications network to the remote computer system, to receive feedback data from the remote computer system and to provide a visual presentation of the feedback on its display. The monitor module has the ability to receive and transmit data. Data transfer between the monitor module and the interactive TV is person-initiated and/or an automatic process. The interactive TV can have a separate remote control which is used to control data transfer, or the monitor module can act as a remote control for the interactive TV.

A problem of the known method is that it imposes relatively many additional requirements on the specifications of the equipment, in particular the remote control unit. SUMMARY OF THE INVENTION

It is desirable to provide a method, portable device, system and computer program that can be implemented with relatively few demands on the specifications of the portable device, e.g. in terms of its background power consumption and required dedicated user controls, but still provide biofeedback appropriate to a particular user.

This is achieved by the method of providing feedback according to the invention, which method includes: obtaining at least one measurement signal representative of at least one measurement of one of a physiological parameter of the user and a parameter associated with ambient conditions experienced by the user transmitting information corresponding to the at least one measurement signal to the remote system for processing by the system, and enabling at least one feedback signal based on the transmitted information to be rendered in a form perceptible to the user, wherein at least a part of the process of converting the at least one measurement signal into a rendered feedback signal is carried out by the portable unit in dependence on a signal received from the remote system. The portable unit may require the information carried by the signal as input or merely use the signal as a trigger. In either case, at least some processing of data - examples include the background execution of logic determining when to execute certain steps of the method and the provision of output data when the process of converting measurements into feedback - is actually being carried out, need not be carried out continually by the portable unit. This is achieved without the need to delegate control to the user, making the system simpler to use. By having the portable unit transmit information corresponding to the at least one measurement signal to the system controlled by the portable unit, for processing by the system, the processing requirements imposed on the portable unit can be kept at a relatively low level. An embodiment, wherein the portable unit comprises a remote control unit, includes transmitting control signals for controlling at least part of the functionality of the remote system in response to manipulation by the user.

Because the remote control unit controls remotely at least part of the functionality of a system in response to manipulation by the user, it is likely to be kept in relatively close proximity to the user. By having the remote control unit obtain the measurement signal, the measurement will reflect relatively accurately the context that particular user is in. Moreover, by combining the controls of the remote system and the monitoring function in one device, more efficient use is made of transceivers for two-way communication between the portable unit and the remote system.

An embodiment of the method includes receiving at least one feedback signal transmitted to the portable unit from the remote system, and causing the feedback signal to be rendered in a form perceptible by the user.

Particularly in a situation where there are several persons in the environment in which the remote system and portable unit are located, this enables the feedback to be targeted at only one of them. Generally, this would be the person to whom the measurement signal on which the feedback is based applies. This embodiment is also suitable for providing certain types of feedback, such as tactile feedback, which cannot otherwise be provided readily. In an embodiment of the method, transmission of information corresponding to the at least one measurement signal to the remote system for processing by the system is triggered by a signal received from the remote system.

An effect is to lower the background power consumption of the portable unit, since it need not continuously transmit information corresponding to the measurement signal or signals. Instead, the remote system polls the portable device. This effect also makes it easier to implement a system in which the remote system processes information corresponding to measurement signals for several portable units.

In a variant, the remote system includes functionality independent of the processing of the information corresponding to the at least one measurement signal, which functionality is at least partly controlled by the remote control unit.

As a consequence, only one remote control unit is required. The biofeedback functionality is integrated into an assembly comprising a remote control unit and an appliance with functionality more or less unrelated to the provision of biofeedback. The remote control unit used to operate the appliance requires frequent handling, making it suitable for use as a means for providing information corresponding to measurement signals characterizing the context the user is in.

In an embodiment, the remote system renders in perceptible form an output signal at least partly derived from an input signal independent of the at least one measurement signal. An effect is to increase the range of use of the assembly of portable unit and remote system. A further effect is that the feedback based on the at least one measurement signal is rendered in a less obtrusive perceptible form. The information content of the feedback can be provided together with the information content of the input signal. In a variant, the remote system modifies the output signal in dependence on the information corresponding to the at least one measurement signal.

An effect is to enable all perceptible output to be consistent, and appropriate to the personal context of the user.

In an embodiment, the remote system comprises an ambient system, wherein the ambient system is adjusted at least partly in accordance with the information corresponding to the at least one measurement signal.

An effect is to provide a form of output that can always be adapted to the physical state of the user, since this is the primary function of an ambient system. This variant takes account of the fact that it is not always possible or desirable to modify the playback or selection of content such as movies or music in accordance with the physical state of a user. Even where such modification is possible, and is carried out, appropriate adaptation of an ambient system enhances the effect provided by the content rendering system.

In an embodiment, the information is transmitted to a remote system arranged to process information received from at least one further portable unit and corresponding to at least one measurement signal representative of at least one measurement of one of: a physiological parameter of a user of the portable unit concerned and a parameter associated with ambient conditions experienced by the user of the portable unit concerned. An effect is to enable the provision of feedback relating to the physical state of members of a group of persons. This can be used e.g. to gauge or moderate audience reaction to content being rendered. An alternative application is in the context of group training exercises. Feedback can be provided, for example, to the trainer.

According to another aspect, the portable device according to the invention includes: an arrangement for obtaining at least one measurement signal representative of at least one measurement of one of a physiological parameter of the user and a parameter associated with ambient conditions experienced by the user; and a transceiver arrangement for two-way communication with the remote system, wherein the portable device is arranged to transmit information corresponding to the at least one measurement signal to the remote system, for processing by the system, and to carry out at least a part of a process of converting the at least one measurement signal into a feedback signal rendered in a form perceptible to a user in dependence on a signal received from the remote system.

The level of resources required to be present in the portable device to provide it with the feedback functionality is relatively low.

An embodiment is configured to execute a method according to the invention.

According to another aspect, the system according to the invention includes: a transceiver arrangement for receiving the information corresponding to the at least one measurement signal from the remote portable unit, and for providing a control signal causing the remote portable unit to carry out at least a part of a process of converting the at least one measurement signal into a feedback signal rendered in a form perceptible to a user.

The system is specially adapted for use in conjunction with a fairly simple portable device to provide tailored feedback to a particular user. An embodiment of the system is configured to function as the remote system in a method according to the invention.

According to another aspect of the invention, there is provided a computer program including a set of instructions capable, when incorporated in a machine-readable medium, of causing a system having information processing capabilities to perform a method according to the invention or to provide the system with the functionality of a system according to the invention.

BRIEF DESCRIPTION OF THE DRAWINGS

The invention will be explained in further detail with reference to the accompanying drawings, in which:

Fig. 1 is a schematic block diagram of a remotely controlled digital television; Fig. 2 is a flow chart showing steps in a method executed by the remote control unit of Fig. 1; Fig. 3 is a flow chart showing steps executed by the digital television and remote control unit in order to provide feedback to a user; and

Fig. 4 is a schematic diagram of a multi-user configuration including the digital television.

DETAILED DESCRIPTION

A digital television system 1 is adapted to provide feedback based on the physical state of a user of a remote control unit 2. The digital television system 1 receives information corresponding to at least one measurement signal representative of a physiological parameter of the user or a parameter associated with ambient conditions experienced by the user and measured in close proximity to the user. Depending on the values of the parameters, different types of feedback are provided to the user according to a heuristic or algorithm. The feedback may be informative, or it may be functional, for example intended to influence the physical state of the user, e.g. by making him or her relax, feel more alert, more comfortable, etc. Such feedback based at least indirectly on a measurement in the user's personal context will also be referred to herein as biofeedback.

Although the example of a digital television system 1 is used, it is possible to implement the methods outlined herein using other types of remotely controlled systems with an interface for two-way communication with a remote control unit. Examples include other types of consumer electronic appliances, but also industrial equipment, so long as they are provided with data processing capacity. Generally, such systems will have functionality that is independent of the provision of biofeedback, but which is already controlled using a remote control unit. To control this functionality, the user will be making frequent user of the remote control unit. This situation is exploited to obtain up-to-date measurements. Returning to the specific example, the remote control unit 2 is provided with an interface 3 for two-way communication with the digital television 1, which is provided with a corresponding interface 4. The interfaces 3,4 are generally adapted for communication over a distance greater than the personal space of the user, e.g. more than about 1 m. Suitable interfaces are wireless interfaces, e.g. for optical or radio frequency communication. Possible embodiments include infra-red interfaces and interfaces based on the Bluetooth or Zigbee communication protocols. For continuous feedback, a wireless radio link would be useful, because it does not require a line of sight that can be interrupted.

In the illustrated embodiment, the remote control unit 2 includes a controller 5 for signal processing. It also includes user controls 6 for manipulation by the user. These may be in the form of mechanical buttons, a touch screen interface, accelerometers, optical movement sensors like those comprised in computer mice or other suitable types of interface. Direct manipulation is not required. Any interface for detecting expressions of will by a user in close proximity is suitable. In this respect, it is noted that the remote control unit 2, although being arranged to move about with the user, need not be carried in the hand, but can be strapped to the user's body, comprise a head-set, etc.

In the illustrated embodiment, the remote control unit 2 comprises both an internal sensor 7 and an interface 8 to an also portable sensor unit 9. The portable sensor unit 9 includes a similar interface 10, a sensor 11 and a controller 12. As an example, the portable sensor unit 9 may be strapped to the user's body whilst the remote control unit 2 is handheld. In any event, the remote control unit 2 is thus enabled to obtain measurement signals of a physiological parameter of the user or a parameter associated with ambient conditions experienced by the user.

Typical sensor for measuring a physiological parameter include photoplethysmographs, skin thermometers, electrodes for measuring the galvanic skin response, electrodes for obtaining an Electro Cardiogram, etc. Examples of sensors for measuring a parameter associated with ambient conditions experienced by the user include optical sensors for measuring the intensity and/or color of ambient light in the vicinity of the user, a temperature sensor to measure room temperature, a microphone to measure the ambient noise level, etc.

The remote control unit 2 further includes at least one output device 13 for rendering a signal in a form perceptible to the user. Feedback may be visual, audible, or tactile or a combination. For example, the output device 13 can include a loudspeaker, a light that changes color or intensity, or an arrangement of lights, a so-called nimbler or other type of device for providing force feedback. It may even include a heating or cooling device for adjusting the temperature experienced by the user handling the remote control unit 2.

In the illustrated embodiment, the remote control unit 2 includes a simple data processing unit 14 for processing the measurement signals and converting them into at least one signal for rendering by the output device 13 according to a simplified algorithm. The purpose of this is to enable the remote control unit 2 to function in a stand-alone mode in situations where the digital television 1 is not available, as will be explained. However, the digital television will under normal circumstances determine the appropriate values of the feedback signal that is to be rendered in perceptible form. The controller 5 and data processing unit 14 may be combined in an alternative embodiment. The digital television 1 includes a receiver interface 15, e.g. a terrestrial, cable or satellite interface, a tuner 16, a demodulator 17 and a demultiplexer 18, as well as a switching device 19 for switching between streams of digital audio, video or data streams. In the illustrated embodiment, content data can also be retrieved from a mass storage device 20, representative of a class of devices that includes optical disk drives, hard disk drives, solid state storage devices, etc.

Video data is rendered in perceptible form by means of a display 21 and display driver 22. Audio data is rendered in perceptible form by an audio decoder 23 and output stage 24 for providing audio signals to a sound system (not shown). In the illustrated embodiment, an ambient system comprising an ambient output device 25 is integrated into the digital television 1 , which is also provided with the appropriate output stage 26 for providing a signal for adjusting an external device 27, e.g. an ambient lighting device. In an alternative embodiment, the ambient system is connected to a bus for home automation to control a variety of devices in the user's house. The integrated ambient output device 25 can be part of a system known as ambilight, comprising a series of Light Emitting Diodes arranged around a screen of the display 21, which change color and/or intensity in accordance with a script provided with the content, so as to match the content in terms of the mood conveyed.

The digital television 1 operates under the control of a central processing unit 28 having access to main memory 29 and arranged to execute software stored in nonvolatile memory 30.

Turning to Fig. 2, the user controls 6 on the remote control unit 2 allow the user to control the biofeedback functionality of the digital television 1 and remote control unit 2. This may be via dedicated keys on the remote control unit 2 or via general purpose keys that control a menu provided on-screen by the digital television 1. Thus, the user will activate (step 31) the biofeedback function using the user controls 6.

The remote control unit 2 will, at the latest at this stage, commence (step 32) obtaining measurement signals representative of the measurements of one or more physiological parameters of the user and/or one or more parameters associated with ambient conditions experienced by the user.

Subsequent to the first step 31, it is also determined (step 33) whether the digital television 1 can be used to process information corresponding to the measurement signals obtained by the remote control unit 2 for the purpose of converting it into appropriate feedback signals. In an embodiment, this determination 33 is carried out by the remote control unit 2, and can therefore comprise determining whether the digital television 1 is within range and/or switched on. In another embodiment, the digital television 1 determines whether its settings allow it to participate.

If the digital television 1 cannot be used, then the remote control unit 2 executes (step 34) a simple routine to determine locally the appropriate feedback to be provided. Using the information obtained in the preceding step 32, the measurement signals are converted into a feedback signal for local rendering in accordance with the predetermined, simple routine.

The routine may be stored in memory (not illustrated separately) or hard-wired into the data processing unit 14. It can be in the form of characteristics, using e.g. stored support values and an interpolation algorithm. The support values are based on empirically derived relations. The types of signals required to obtain a certain biological effect are known. Representative examples of the effects of such signals are given in the following three references, for example: Schein, M. et ah, "Treating hypertension with a device that slows and regularizes breathing: A randomized, double-blind controlled study", Journal of Human Hypertension, Ii, pp. 271-278;

Yucha, CB. et ah, "The Effect of Biofeedback in Hypertension", Applied Nursing Research, 14 (1), February 2001, pp. 29-35; and Lehrer, P. et al, "Respiratory Sinus Arrhythmia Biofeedback Therapy for

Asthma: A Report of 20 Unmedicated Pediatric Cases Using the Smetankin Method", Applied Psychophysiology and Biofeedback, 21 (3), September 2000, pp. 193-200(8).

Thus, as an example, the remote control unit 2 can be used for breathing exercises, using e.g. colored lights as the output device 13 to indicate whether the user's breathing is too fast or too slow.

The feedback is limited to that which can be provided using the output device 13 available locally to the remote control unit 2. It is further limited by the processing capacity of the data processing unit 14. On the other hand, using the local feedback facility, the user of the remote control unit 2 can obtain biofeedback without disturbing other persons present in the vicinity of the television 1. Indeed, the user can take the remote control unit 2 to another room, or at least out of range of the television 1.

If it is determined that the television 1 can be used for facilitating the provision of feedback, some or all of the steps illustrated in Fig. 3 are carried out. The remote control unit 2 carries out at least one of the steps in the process of converting measurement signals into rendered feedback signals in dependence on a signal received from the digital television 1. In the variant of Fig. 3, two such steps depend on a preceding signal from the digital television 1. In order to keep the power consumption of the remote control unit 2 low, the digital television 1 can poll (step 36) the remote control unit 2 for information corresponding to at least one measurement signal representative of a physiological parameter of the user and/or a parameter associated with ambient conditions as experienced by the user. In response, the remote control unit 2 returns (step 37) such information, which may be a pre- processed version of the measurement signals obtained from the sensor unit 9 and/or the internal sensor 7, or may correspond directly to the sample values. Therefore, the transmission of information corresponding to at least one measurement signal for processing by the digital television 1 is triggered by a signal received from the digital television 1. It is noted that this feature may be implemented in such a way that the preceding step 32 of obtaining sensor data, at least where data from the sensor unit 9 is concerned, is also carried out only upon receiving the polling signal. In any case, it will be clear that the process of converting the part of the measurement signals obtained in the preceding step 32 into feedback to be rendered subsequently is dependent on receiving a polling signal from the digital television 1. The digital television 1 receives the information corresponding to the measurement signals, and analyses (step 38) the information. This analysis 38 can be more processing-intensive than the corresponding step 34. For example, the digital television 1 may carry out averaging, digital filtering or frequency analysis on the signals received from the remote control unit 2. Using, e.g. a database 39 storing pre-determined relations between measurement signal values and feedback signals, the digital television 1 determines (step 40) the appropriate feedback.

Different types of feedback can be provided, and in different ways, a multitude of which are illustrated in Fig. 3. Other embodiments may employ different or fewer types than those illustrated. A first type of feedback uses the fact that the digital television 1 renders in perceptible form an output signal that is at least partly derived from an input signal that is independent of the measurement information received from the remote control unit 2. In particular, the digital television 1 renders in perceptible form the audio-visual signals obtained using the tuner 16, demodulator 17 and demultiplexer 18, or audio-visual signals stored on the mass storage device 20, e.g. a DVD in an optical disk drive. Depending on the values of the measurement signals, the digital television 1 modifies its selection of content from the content available in the input signal and/or edits the selected content (step 41). For example, a program carried in MPEG-2 elementary streams may comprise several variants, carried in separate elementary streams and identified in the Programme Map Table associated with these streams. The digital television 1 can select the appropriate elementary streams based on the values of the measurement signals it has received. For example, if the measurement signals demonstrate that the user has a high pulse rate or is otherwise very agitated, the digital television 1 can select a less violent or less gory version of a horror movie played back from disk. Alternatively, it can edit the video signal by removing scenes of certain color. In another example, e.g. where the viewer is known to suffer from certain afflictions (e.g. migraine), biological measurements can be used to edit the video signal in an appropriate manner.

Secondly, the digital television 1 can automatically adjust its settings, e.g. the amplification settings for the audio component of audiovisual signals and/or the brightness values of the video component, in dependence on the information based on the measurement signals and received from the remote control unit 2.

In the illustrated embodiment, the digital television 1 comprises an ambient system, a system to generate perceptible effects corresponding at least partly to the content being rendered. In this case, the perceptible effects are adapted also in dependence on the measurement signals obtained by the remote control unit 2. For example, lighting may change to a less aggressive color or lower intensity if the user is determined to be agitated. Alternatively, the lighting may start to flash, increase in intensity or adjust to a primary color if it is determined that the use is less alert. Finally, the remote control unit 2 is employed to render at least one of the feedback signals provided by the digital television 1 in perceptible form. The digital television 1 transmits (step 44) a control signal corresponding to the feedback signal to the remote control unit 2. The latter receives (step 45) the signal and proceeds to cause (step 46) the output device 13 to render the feedback signal in a form perceptible by the user. It will be appreciated that this step 46, like the first step 37 is thus carried out in dependence on a signal received from the digital television 1. The remote control unit 2 can thus provide feedback perceptible primarily by the user thereof. Because the feedback is determined predominantly by the digital television 1 with its advanced data processing capacity, the feedback can depend in a quite elaborate way on the measured values of biological signals. Fig. 4 illustrates a further variant, suitable for use in a multi-user environment. A first remote control unit 47 corresponds to the remote control unit 2 described in detail hereinbefore. It thus comprises both user controls 48 and an output device 49. Further portable units 50-52 comprise a sensor and/or sensor interface (not shown) for obtaining at least one measurement signal representative of at least one measurement of a physiological parameter of its respective user and/or a parameter associated with ambient conditions experienced by the respective user. However, these portable units 50-52 comprise only a respective output device 53-55. Each transmits information based on measurement signals obtained by it to the digital television 56 or other remote system for processing. This may be done in response to a polling signal.

The digital television 56 calculates the appropriate values of feedback signals. Feedback can be rendered in perceptible form using e.g. an ambient lighting device 57 comprised in the digital television 56. Feedback signals are also transmitted to the first remote control unit 47 for rendering in perceptible form, as well as to the individual portable units 50-52. It is appropriate to transmit to the portable units 50-52 respective feedback signals based only on measurement information received from them individually, and to transmit to the first remote control unit 47 a feedback signal based on measurement signals received from at least one of the portable units 50,51,52. Thus, the first remote control unit 47 can be used for instance by a teacher, and the other portable units 50,51,52 by his or her pupils.

Alternatively, the portable units 50-52 can be provided with limited user controls, allowing them to connect to selected ones of the other portable units 50-52 and/or the first remote control unit 47 so as to receive the feedback signal based on that unit's measurements from the digital television 56. Optionally, the user may select to receive feedback based on the physical state of the users collectively. This feature can be used to ascertain the mood in the room or the mood of another person in the room (without having to ask them).

It should be noted that the above-mentioned embodiments illustrate, rather than limit, the invention, and that those skilled in the art will be able to design many alternative embodiments without departing from the scope of the appended claims. In the claims, any reference signs placed between parentheses shall not be construed as limiting the claim. The word "comprising" does not exclude the presence of elements or steps other than those listed in a claim. The word "a" or "an" preceding an element does not exclude the presence of a plurality of such elements. The mere fact that certain measures are recited in mutually different dependent claims does not indicate that a combination of these measures cannot be used to advantage.

For example, instead of automatically modifying or adapting the selection of content data, the digital television 1 can be used to suggest TV content to a user based on his current physiological state, or to restrict access to users that are in certain physiological states. It can also be used to assess the age of the user and restrict content based on this inference, e.g. using heuristics to infer the user's age from biological data.