Proximity Detection. Technology Briefing Paper

Transcription

1 22 Boulder Rd Malaga W. A Australia tel fax Proximity Detection ABSTRACT This paper provides a status report on the development of Proximity Detection. This system is aimed at collision avoidance in busy industrial sites where heavy machinery operates near personnel and light vehicles. HIGHLIGHTS Generation change in mining technology Two years of engineering development $1 million Federal Government development grant awarded (Stage 1) Alliances with leading industry partners in field trials Document Revision: 2.3 Date: 21/04/2005 Security: Commercial-In-Confidence MKT0055 Page 1 of 9 22/04/2005

2 INTRODUCTION Driven by changes in Occupational Health and Safety (OH&S) regulations and liability insurance, industrial sectors have been put under increasing pressure to protect their staff, plant and equipment from accidents. A large number of accidents in the workplace namely in mining result from collisions between personnel and/or machinery. All major industry segments are thus searching for systems that will reliably and accurately provide distance measurement for early warning and prevention of probable collision. RF Innovations hopes to break into the market for Proximity Detection (estimated US$1 Billion) within the next 12 months. The current Proximity Detection system is a result of two years of Research and Development (R&D). This R&D was internally funded with assistance from the Federal Government in the form of an AusIndustry Start grant. Many of the technical hurdles in the application of Proximity Detection have been overcome with the current design. Our Proximity Detection technology is primarily aimed at safety-critical applications, where the risks of personal injury and equipment damage are a primary concern. RF Innovations believes this technology will ultimately help reduce the risk of accident in the workplace and therefore provide a safer working environment, with lower downtime and liability risks. Applicable scenarios range from mining - both above and below ground - to loading yards, train terminals and anywhere where people or light vehicles coexist with heavy mobile machinery. Proximity Detection systems can be mounted on cranes, forklifts, LHDs, trains or worn by personnel. The technology is currently being field-trialled in demanding industrial environments and has already shown the potential to take a large share of the market. Figure 1: Heavy machinery protection zones with vehicles and personnel (concept operation) RF Innovations is currently seeking expressions of interest from partners for further development and commercialisation of its Proximity Detection technology. Commercial-In-Confidence Page 2 of 9 22/04/2005

3 SYSTEM OVERVIEW The Proximity Detection system operates in free-to-air radio frequency spectrum and provides mechanisms to automatically indicate when heavy machinery and vehicles or personnel come within the nominated distance of each other. The system detects the distance between antennas of masters and slaves, compares it against preset distance thresholds and accordingly takes pre-defined fail-safe actions. Pre-defined actions may include audio / visual indications of threshold crossing and machine control. Both distance and speed are conveyed via SCADA 4-20mA current-loop outputs, in addition to other discrete outputs. The master system also provides a host development interface for system integrators. Operation Zone Warning Zone Danger Zone Master Unit Operation Zone Warning Zone Danger Zone Master Unit Figure 2: Proximity System architecture Figure 2 illustrates Proximity System operation. Master units and associated RF transceivers are typically mounted on heavy machinery. units and associated RF transponders are mounted on light vehicles or personnel units. In the example above the s can be Personnel worn small Transponder and battery device, or vehicle mounted Transponder and operator display. The unit can also be integrated for temporarily installation on visiting vehicles or fixed position installation to protect buildings or other infrastructure. In the above system the location of the six s and other Masters can be reported from up to eight locations around the Master. Commercial-In-Confidence Page 3 of 9 22/04/2005

4 The Master transceivers provide unambiguous coverage and redundancy. The Master itself manages the distance information processing and management and the user outputs. The Master continually outputs the distance of all other units within range. The Master also provides three relay outputs that can be set to trigger when the respective thresholds are crossed by the closest unit. The current Proximity Detection system can be set for a maximum operational distance of 100m with a resolution of 1 meter. Warning thresholds can be set for each Transponder independently, and the armoured cable run to the Master unit is automatically factored into the distance calculation. FEATURES Accurate distance detection combined with timely reaction Relative velocity of closest slave Fail-safe system implementation Multiple co-located masters Shared transponders between co-located masters and ability of transponder to respond to more than one master at any given time Multiple (up to 8) master RF transceivers to provide arbitrary shape RF coverage Master-to-master ranging Ability to recognise the difference between transponder out-of-range and transponder drop-out MASTER UNIT OUTPUTS Fail-safe zone alarms for user-configurable distance thresholds Serial distance output (all slaves in range) 4-20mA distance output (closest slave) 4-20mA relative velocity output (closest slave) Alarm outputs: self-test failure, low data quality, low measurement rate SLAVE UNIT TRANSPONDER OUTPUTS Self test (audible and visible alarm) Aliveness indicators Commercial-In-Confidence Page 4 of 9 22/04/2005

5 EXISTING SOLUTIONS There are a few existing technologies on the market aimed at providing proximity measurement within an industrial environment. Some of these technologies and associated problems are tabled below: Passive Radar Distance detection via passive radar (ultrasound or radio-frequency) Only suitable for short-range point-to-point distance measurement (e.g. bumper-tobumper). These systems are inadequate for multi-user perimeter crossing detection. Radio (Received Signal Strength) The strength of the received radio signal is used to infer distance, based upon the knowledge of the transmitted signal Systems that rely on signal strength to compute range are unsuitable for safety decisions due to the widely fluctuating signal resulting from multipath effects. GPS Global Positioning Satellite is used to determine target positions. Relative position is determined over a network which can also be used for collision avoidance information exchange purposes. GPS does not work underground or in deep cuttings. Relies on complex network to establish relative positions (DGPS). Is expensive to get 1 metre accuracy or better. Difficult to apply technology to cover personnel. Video Video cameras (namely infrared) are mounted at different vantage points on machinery. Operator monitors video images. Optional support by pattern recognition for collision avoidance purposes. Strong limitations in dusty or muddy environments and at night time. Human intervention tedious after extended periods and subject to human error. 360 degree coverage expensive to implement. Laser Laser beams or curtains used for barrier crossing or close proximity detection. Laser safety systems are widely used in industry. They are however limited to short distances. Highly directional beams reduce their usefulness in wide angle coverage applications. RFID Radio Frequency Identification Tagging (RFID) used to detect proximity RFID can indicate target identity within a certain radius but cannot reliably indicate target range or velocity. Commercial-In-Confidence Page 5 of 9 22/04/2005

6 TECHNICAL ACHIEVEMENTS Major practical hurdles have been overcome during the Proximity Detection R&D phases. The resulting technical achievements represent both significant barriers to the potential competitors and commercial advantages to RF Innovations and its partners. Some highlights of the hurdles overcome and summary of solutions devised are presented below: Heavy vehicle perimeter protection Large mass, shape and sometimes variable perimeter geometry, commonly associated with heavy machinery, preclude singlepoint 360 degree RF or ultrasonic coverage. A prime example is that of a digging machine with its digging bucket. Drivers have limited visibility and the bucket is at a considerable distance from the cab. RF Innovations has developed credit-card size RF transceivers. These transceivers can be mounted at strategic points around the machine and deliver near 180 degree RF coverage. The RF transceivers are compact and rugged and suitable for mounting in heavy machinery, including the under-body. Comprehensive periodic self-tests ensure correct system operation, including master to transceiver cabling. Coexisting heavy vehicles and personnel In typical industrial sites, such as mines, people and support vehicles may share a common confined area. It is often required for multiple heavy vehicles to concurrently operate in close vicinity of plant, equipment and personnel. Maintaining safe working conditions for all is a major challenge, particularly in harsh, noisy and dusty environment, common in mine and construction sites, dockyards and metal smelters. RF Innovations solution permits a large number of masters and slaves to share a same working area. A master is commonly associated with a heavy vehicle, whilst a slave includes personnel or light vehicle units. The current system supports up to 512 colocated slaves and masters. Each unit has a unique ID in the system. Each master is aware of all slaves within RF range AND other masters. The design caters for graceful entry and exit of Proximity Detection units they come into range and leave the site. Dangerous closing velocities. Simultaneous distance and closing-in speed determination are required to maintain safe working perimeters, both for personnel and machinery. This requirement arises from the need to discern stationary from moving targets and targets exceeding maximum allowed closing-in speed. In addition to relay outputs for e.g. emergency braking, RF Innovations system provides data to calculate the relative closing velocity of the closest target. A post-processing serial data stream is available for system integrators over a development interface. Commercial-In-Confidence Page 6 of 9 22/04/2005

7 Redundancy In addition to ruggedness and reliability, it is vital for proximity detection system to incorporate some form of redundancy. Redundancy should include overlapped coverage and distributed fail-safe operation. RF Innovations Proximity Detection provides comprehensive system redundancy associated with fail-safe operation: Each master supports 8 RF transceivers. Each 90 degree sector is covered by dual-redundant RF transceivers; Each transceiver is self-tested upon master transmission. On malfunction the system will revert to fail-safe mode; s are interrogated typically 1000 times per second in a lightly loaded network Ungraceful slave drop-out can be detected by the master and failsafe action taken. Ease of installation, accurate operation Commercial systems are required to be easily set up and configure, in a set-andforget manner. In a safety-critical perimeter protection application, it is essential continuous selfcalibration for accurate and reliable distance detection. RF Innovations design simplifies installation and ensure reliable run-time accuracy, even in the most demanding application: Transceiver and slave antennas are wide aperture and do not require precise alignment; System configuration is facilitated by state-of-the-art PC-based Java network management GUI and embedded agent; All critical cabling is self-calibrating and continuously self-tested; The operational range is 1 to 200m, resolution +/-1m, accurate to +/- 1m at close range, +/-2m at far range Commercial-In-Confidence Page 7 of 9 22/04/2005

8 DEVELOPMENT PROGRESS RF Innovations Proximity Detection technology is the result of more than two years of intense R&D. We have progressed through study and trial of a number of ranging techniques to our chosen time-of-flight, digitally coded, low-power active pulse radar system. Our initial system (a.k.a. analogue proximity ) was developed and tested in These units were used in industrial applications with limited success. In the later part of 2004 we embarked on the development of our Phase 1 system ( a.k.a. digital proximity ) under an AusIndustry Start grant. Phase 2 will focus on product development and commercialisation of Phase 1 technology. A summary of the project status is provided below. PHASE 1 Phase 1 is currently undergoing field trial. The results of the trials will permit RFI to refine the design. Trials underway in Perth show promising results. Phase 1 completion may involve a potentially wider release of Phase 1 systems. Phase 1 systems are yet to be made available for wider industry trials and customer application development. It is clear to RF Innovations and its partners that its Proximity Detection is technologically well ahead of all known systems. The trial systems have been operating in extremely harsh environments, proven to accurately measure distances in excess of 100m and provide timely reaction within 200ms. Further trials are being prepared. Concurrent with the above, RFI is finalising the multi-master system development. This system will permit masterto-master ranging. Such system will allow e.g. several heavy vehicles to communicate with slaves and among themselves on common work sites. PHASE 2 Upon finalisation of Phase 1, RF Innovations intends to embark on further development of the Phase 1 system for alternative frequency bands and channel allocations, allowing worldwide deployment. Phase 2 will also include customisation for different applications and cost reduction via volume production. Phase 2 will include: - Narrowband ranging in licensed UHF and VHF channels; GHz spread-spectrum solution; - Customisation and volume manufacture. Timely Phase 1 and 2 completion will allow RF Innovations to be first to market and deliver a comprehensive Proximity Detection solution suitable for all major industry segments. Commercial-In-Confidence Page 8 of 9 22/04/2005

9 PROXIMITY DETECTION MARKET According to a professional marketing report commissioned by RF Innovations prior to applying for the AusIndustry grant, the potential market is in excess of US$1Billion. RF Innovations is confident to seize a significant share of this potential market due to its current technical advantage over the known competition. PLANNED ROUTES TO MARKET RF Innovations plans to implement OEM channels for marketing and distribution. The technology will be released to major industry partners to take advantage of industry-specific knowledge. These distribution channels will allow RF Innovations to focus on its core wireless technology expertise. It is foreseen that the developed technology will be customised to customer-specific applications. Example applications range from simple as a perimeter alarm systems to complex integrated proximity systems, with comprehensive personnel and asset tracking applications. Commercial-In-Confidence Page 9 of 9 22/04/2005