"Manually Operated Signalling Apparatus"
The present invention relates to signalling apparatus which is manually operable by a user for transmitting signals to some type of apparatus, computer system or the like adapted to receive input signals from the user. The signals may comprise command signals for controlling the operation of the apparatus, computer etc., or data signals for supplying information to apparatus, computer etc.
The invention is particularly intended for use by surgeons in controlling the operation of assistive machinery and instrumentation, most particularly in the field of minimal access surgery (MAS). However, the invention is also useful in other fields of application.
Existing apparatus for the control of assistive machinery and instrumentation used in MAS generally requires the surgeon to make awkward movements, to release the handles of instruments being used in the procedure, or to otherwise distract the surgeon's attention from the procedure. One existing system operates by detecting movements of the surgeon's head
within a magnetic field, but this is also awkward and unnatural .
It is an object of the present invention to provide improved devices enabling signals to be transmitted by a user of the invention in a manner which is unobtrusive and unobstructive, and which provides minimal distraction to the user from other activities.
In accordance with the invention there is provided manually operated signalling apparatus comprising: a signalling device including actuating means and being adapted to generate at least one output signal in response to operation of said actuating means; and means for removably attaching said actuating means to at least one finger or thumb of a user.
The actuating means may comprise any type of device which can generate a signal in response to movement of a finger or relative movement of or contact between two or more fingers so as to provide at least a simple toggle or binary (i.e. "on/off") signal.
The actuating means may comprise at least one type of device selected from the following: pressure sensitive devices; contact sensitive devices; proximity sensitive devices; velocity sensitive devices; acceleration sensitive devices.
Pressure and/or contact sensitive devices suitable for the purposes of the invention may include, for example, switches, miniature joysticks, track-balls, pressure- pads or tactile elements. Other types of devices may include electrical, magnetic, electromagnetic or
optical devices (including infra-red devices).
In certain preferred embodiments of the invention, the signalling device may include first actuating means located on the thumb tip of the user and at least second actuating means located on at least one other finger of the user, the apparatus being adapted to generate signals in response to mutual contact between said first and second actuating means. Second actuating means may be located on more than one finger, such that different signals may be generated by contact between the thumb and different fingers.
Alternatively or additionally, multiple actuating means may be located on a single finger tip, each of said actuating means being adapted to generate a different signal.
The means for removably attaching said actuating means to a first finger or thumb of a user is preferably adapted to locate the actuating means such that it may be operated by pressure applied by an opposed thumb or finger of the user. Most preferably, for surgical applications, the actuating means is adapted to be located at the tip of said at least one finger or thumb of the user. The means for removably attaching said actuating means preferably comprises a sheath configured to fit on at least one fingertip of the user, the signalling device being secured to the sheath. Alternatively, the actuating means may be incorporated into a glove (such as a surgical glove).
The actuating means may be mounted on a flexible circuit board secured to or incorporated within the sheath, glove or the like.
The apparatus preferably further includes means for transmitting signals from the signalling device to other apparatus adapted to receive input signals from the user. The signal transmission means preferably includes wireless communication means including a wireless transmission module connected to said signalling device and adapted to transmit wireless signals to said other apparatus in response to signals received from said signalling device. The wireless transmission may be by radio, optical or ultrasonic means, or by any other suitable wireless transmission medium.
The wireless transmission module is preferably portable and is adapted to be carried by the user. Most preferably, said wireless communication means is adapted to be secured to the wrist or arm of the user.
The wireless communication means preferably also includes receiver means connected to or forming part of said other apparatus.
Embodiments of the invention will now be described, by way of example only, with reference to the accompanying drawings in which:
Fig. 1(a) is a schematic illustration of a first embodiment of signalling apparatus in accordance with the invention;
Figs. 1(b), 1(c) and 1(d) are schematic illustrations of details of the embodiment of Fig. 1(a); and
Fig . 2 is a schematic illustration of further embodiments and features of the invention .
Referring now to the drawings, Figs. 1(a) - (d) show a first example of fingertip-mounted signalling apparatus in accordance with the invention. In this example, the apparatus includes actuating means in the form of a miniature joystick 10, configured as a thimble-type device for fitment to the tip of a finger 12 of the user's hand 14. The joystick 10 comprises a generally cylindrical body 16 which fits onto the fingertip and having an upper end face 18. A resilient rod-like member 20 projects upwards from the end face 18, and has a disk-shaped member 22 attached to the upper end thereof. Four contacts A, B, C, D are spaced around the periphery of the end face 18, such that the disk 22 may be manipulated by the thumb 24 of the user to selectively contact individual ones of the contacts A, B, C, D. The disk 22 and rod 20 include electrically conductive means (not shown), so as to constitute a fifth electrical contact E. Accordingly, the joystick acts as an array of switches (see Fig. 1(d)), in which manipulation of the joystick selectively closes individual switches.
Wiring 26 connects the joystick 10 to a miniature transmitter unit 28, which generates different signals in response to operation of the various joystick switches. The transmitted signals can be detected at a remote location and used as data or command signals for any required purpose. A joystick of this type might typically be employed to control the direction of movement of robot apparatus.
Fig. 2 illustrates a number of variations on the invention, including different types of finger-mounted signalling device which are described in greater detail below. In each case, signals from the devices are transmitted from a transmitter unit 30, similar to the
unit 28 of the first embodiment, to a remote receiver unit 32. The signals are preferably transmitted by wireless means, which may be of any suitable type such as radio, optical or ultrasonic means. The signals received by the receiver unit 32 are passed to a controller unit 34, such as a computer, where the signals are processed and converted into control or data signals for any required purpose; e.g. for controlling a robot manipulator or other apparatus 36. It will be understood that the receiver 32, the controller 34 and the apparatus, device, or the like 36, constituting the "end-user" of the signals, may comprise separate or integrated units as required by the particular application of the invention. Preferably, a programmable controller unit would be provided allowing the invention to be adapted for use with any required "end-user" apparatus.
In its simplest form, the apparatus comprises a signalling device in the form of a tactile sensor 38, such as a microswitch, pressure sensor, or other actuating means responsive to applied force, for example, on the index finger of the user's left hand and actuated by pressure applied by the user's left thumb to the actuating means. The signalling device may thus be operated by a simple pincer-like movement of the right thumb and middle finger. The invention may also employ other types of switches, sensors and the like, including devices which operate on the basis of proximity, relative velocity or acceleration etc. by means of electrical or magnetic fields, optical signals (including infra-red) etc.
A simple toggle switch of this type may be used to generate a simple on/off signal which might be used, for example, to control a surgical cauterising
instrument. Apparatus of this type is conventionally controlled by means of a foot-operated switch, which is awkward and cumbersome in comparison with the present invention. Depending upon the type and arrangement of the actuating device)s), more sophisticated signals may be generated, besides simply on/off signals.
Multiple actuating elements 40 might be mounted on the same finger-tip, allowing a plurality of different signals to be transmitted by operation of different elements (or, possibly, different combinations of elements). An array of four actuating means 40 can provide functionality equivalent to a joystick.
A miniature joystick 42 might differ in construction from that of Fig. 1. In particular, the joystick may be of the "analog" type, generating a signal which varies with both the direction and magnitude of the applied force; e.g by means of strain gauges. Such a device could control, for example, both the direction and speed of movement of a robot device.
As a further alternative, the actuating means might comprise a miniature "track-ball" device 44, of the type which is well known as a pointing device for personal computing applications employing graphical user interfaces.
In order to prevent accidental operation of the end- user apparatus, it may be desirable to provide first actuating means 46 on the thumb of the user's hand and second actuating means 48 on the finger, so that a signal is generated only by mutual contact (or proximity etc) of both actuating means. Second actuating means 48 could be provided on more than one finger, allowing different signals to be generated.
The relevant signals could be generated in response to electrical contact between the respective actuating means 46, 48 completing a circuit, but this may lead to problems arising from inadvertent earthing. It is preferable that the system operates by correlating signals generated independently by contact pressure between or proximity between the respective actuating means 46, 48. Multiple actuating means may again be provided on one or more of the user's fingertips.
In each of the embodiments of Fig. 2, or other variations, the actuating means 38 to 48 are preferably mounted on a flexible circuit board 50 which is secured to the user's finger. The circuit board might suitably be secured by being incorporated into a sheath which fits over an individual finger, or into the finger portion of a glove.
When the relevant signalling device is actuated, the signal generated by the signalling device is received by the transmitter and encoded prior to transmission, together (preferably) with an address code identifying the transmitter, to the receiver 32 situated remote from the user. The controller 34 decodes the signal and forwards appropriate signals to the relevant apparatus 36 (e.g "turn off the cauterising current"; "move the robot gripper left at speed 0.1 s"1, etc.). This wireless system allows the surgeon to control machinery and instruments without the need for trailing wires and cables. The signals provided by the present invention might be employed in combination with commands etc. generated by other means, such as voice control employing known voice recognition systems.
The invention is particularly suited for minimal access surgery applications, but is also suited generally for
remote control applications where the hands and arms are being constantly employed in other tasks (e.g. nuclear glove-box manipulation, computer-based interactive games, etc.). The location of the actuating means on the fingertips of the user is especially suited to MAS applications, since the surgeon's fingertips are generally free even while manipulating conventional MAS instruments.
The invention provides a number of advantages over conventional command and control systems, being simple and unobtrusive, not requiring trailing wires or cables, employing fingertip operation which is "natural" for surgeons and other potential users, and allowing the hands and arms to remain free for other tasks.
Improvements and modifications may be incorporated without departing from the scope of the invention.