GB2460714A

GB2460714A - Electronic device for preventing instability in transport equipment

Info

Publication number: GB2460714A
Application number: GB0810477A
Authority: GB
Inventors: Geoffrey John Harbach
Original assignee: Individual
Current assignee: Individual
Priority date: 2008-06-09
Filing date: 2008-06-09
Publication date: 2009-12-16
Also published as: GB0810477D0

Abstract

One or more electronic circuits boards and gravitational/inertial sensors typically but not necessarily contained exclusively in their own housing (1) typically but not necessarily with a cable and connector for connection to the velocity control system of transport equipment (3) and which typically but not necessarily includes visual and/or auditory warning devices (4) and which enjoys an internal and/or an external power source (11). The purpose of the device is to be mounted to something, (typically transport equipment, but could be anything which needs to be monitored for excessive angle or acceleration), such that a warning is provided when excessive angle is approached, or when accelerations are tending to cause the entity it is connected to - to approach the entities angle of static and/or dynamic instability. The intention is that the driver/person controlling the velocity of the equipment will then take corrective action to restore stability. Optionally the subject of the patent application can electrically interface with the control system of, for example transport equipment such as a powered wheelchair, in order to automatically limit the available speed and/or acceleration in order to reduce the likelihood of static and/or dynamic instability.

Description

Page 1 Electronic device for preventing instability in transport equipment.

This invention relates to a device that senses both the direction of the force of gravity, and can detect the effects of inertial accelerations and decelerations, and can be used to help prevent, for example wheelchair users, from tipping their chairs over by traversing excessive slopes or accelerating too hard.

People who control transport equipment that has the potential to tip over if driven across unsuitable surfaces or across excessive gradients or is accelerated, cornered or braked too hard, have at present no way of telling at what angle their vehicle or equipment is at relative to the vertical direction of the force of gravity. Moreover, when the vehicle or equipment is nearing its limit of static stability, to accelerate or decelerate is likely to add sufficient impetus to cross the boundary of static stability whereupon the vehicle or equipment will fall over, damaging itself, its goods or its driver and/or passengers.

The purpose of this invention is to provide a means whereby the person in control of the vehicle or equipment can receive an auditory or visual warning indication of impending instability and take appropriate action in order to prevent the same. An additional purpose of the invention is for it to interact with the control system of the vehicle or equipment such that the speed is reduced as the static component of the excess angle approaches the limit of stability, and also to limit the available maximum acceleration or deceleration as the static component of the excess angie approaches the limit of stability in the knowledge that an acceleration, when the vehicle or equipment is at a relatively safe angle, can also cause rapid instability. The invention has applications, for example, in the 4x4 off road arenas and the manual and powered wheelchair arenas.

The essential design feature of the invention is such that there is one or more sensing elements that detect both the direction of gravity, (which is in itself an acceleration force), and also inertial accelerations other than gravitational. These are coupled to a control component which takes user settings of allowable stability angles, and, a) presents the user with an indication when instability is imminent, and optionally b) can interact with the vehicle or equipment speed and acceleration control system so as to reduce the likelihood of it approaching or remaining in an unsafe speed I velocity state.

Page 2 The invention will now be described solely by way of example and with reference to the accompanying drawings in which: Figure 1 shows a typical embodiment of the invention, displaying one possibility for the user safe angle input controls.

Figure 2 shows the safe angle input controls in greater detail.

Figure 3 shows the functional block diagram of the system.

One embodiment of the invention is approximately the same size as a large box of matches.

In detail the invention consists of an enclosure (1) and has user adjustments on the outer faces whereby the required warning angle limits can be pre-selected (2). There is optionally a cable and connector (3) which allows the invention to be interfaced to the control system of the vehicle/transport equipment. An audible warning device is included (4) to inform the user of approaching instability. See figure 1.

One implementation of the user angle pre-selection inputs is detailed in figure 2. These consist of a normal electrical potentiometer, secured into a panel by a special "nut" which includes an outer nut (5) which when tightened, causes flexible fingers (6) to grip the pot shaft (7), preventing further adjustment until the outer is un-tightened. This pot shaft locking nut is commercially available and is not being "claimed" as part of the invention. There will be markings (8) on the enclosure next to each adjuster to indicate the approximate angle of pre-set. It should be noted that there are many different forms of pot shaft locking devices, some of which also include a calibrated scale for the precise selling of the adjustment.

Page 3 Another implementation of the adjustment inputs would be by the use of a remote handset, or a connection to a computer, enabling a greater accuracy of input setting.

The functional block diagram, see figures 3, demonstrates how the gravitational and inertial sensors (9) are connected to the central processing and interface unit (12). The input settings from the user inputs (10) also feed into the central processing and interface unit (12) which is most likely to be a programmable integrated controller or PlC processor of some sort. A number of suitable devices are available on the market.

The central processing and interface unit (12) then performs calculations based on the data from the sensors (9) and the user adjustments (10) and generates alarm outputs through the Audio and / or visual warning indications (14).

The central processing and interface unit (12) will require power to operate (11) and this can be provided by internal batteries and/or an external power source. This is likely to depend on whether the vehicle or equipment is itself powered or manual in operation.

An optional feature of the invention is the ability to interface to the control system of the vehicle or equipment such that the speed is reduced as steeper gradients become traversed, and in addition, reduces the available acceleration so as to reduce the likelihood of tipping due to excessive acceleration/deceleration/cornering.

Claims

Page 4CLAIMS1. A device that senses the direction of the force of gravity relative to its own orientation.
2. A device as in 1. above that can also detect the direction and magnitude of inertial acceleration and deceleration forces that it is subject to.
3. A device as in 2. above that accepts user input settings for angles to be used as limits for the horizontal plane axes, against which warnings can be generated if these limits are exceeded. These user setting could be by direct adjustment or by the use of a dedicated removable connected handset or generic computer connection.
4. A device as in 3. above which performs a process on its own measured angular orientation information such that it can be used in an analogue or digital circuit in order to be useful for providing warnings of excessive angle or the potential for instability due to accelerations, (hereafter to be recognised as either positive or negative).
5. A device as in 4. above which can be mounted to equipment and therefore experience the static angles and inertial accelerations of the equipment.
6. A device as in 5. above which has an internal and/or an external power source for the purpose of performing the actions detailed in these claims.
7. A device as in 6. above which has a means of providing a warning signal in any convenient form, e.g. auditory, visual or by data exchange, (where the data may be analogue or digital in nature), indicating the impending approach of instability.
8. A device as in 7. above which can interface to the control system of transport equipment such that speed and/or acceleration of the transport equipment can be limited thereby reducing the likelihood of instability of the transport equipment in use.
9. A device as in 8. above that is manufactured in a robust and environmentally protected fashion, (depending on the nature of the implementation), such that the device can be used in outdoor environments without degradation of its function.
10. A device as in 9 above that can also be classified as a medical device, (due to the competency of its design and manufacture), if used in an application that would so warrant it.