Geomatics Indaba 2016 Stream 2 - EE · by Matthew Bester and Neil Slatcher, 3D Laser Mapping...

Geomatics Indaba 2016 – Stream 2

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Miniaturised laser mapping systems and 21st century support

by Matthew Bester and Neil Slatcher, 3D Laser Mapping

Abstract

Since the introduction of accurate mobile laser scanning systems in a commercial space, the face of mobile

laser scanning or mapping has changed significantly. Huge advances in the technology used for mobile

mapping, has seen the shift from mobile mapping with large bulky systems, to lightweight multi-platform

mapping that allows driving; walking and flying of laser scanners to obtain very high accuracy point clouds.

By looking at the changes and innovations in technology used for mobile laser scanning in parallel, there

should be a concise and serious change in the way these technologies and their users are supported. The

relationship between technology adoption and rate of its change, and the accessibility and efficiency of support

for the users of the technology is paramount.

From the first commercial release of a vehicle-based mobile mapper system in May 2004, telephonic support

and e-mail was the acceptable norm for support. Today we see multi-platform, lightweight and accurate

systems, with multi-level support platforms; user efficiency development and redundancy built into support 24

hours a day 365 days a year. This paper will discuss the roadmap of development for technology and the

requirement for the support of the technology and the users from then until now, and beyond.

Keywords

mobile mapping system, support, ROBIN, multi-platform lidar, multi-level support, mature technology usage

Introduction

Mobile laser scanning became commercially available from 2004 onwards and was developed from airborne

laser scanning technology. Before 2004, the technology was limited due to the following factors: (a) most

airborne lidar systems are not eye-safe (Class I) at short range, thus making it dangerous to be operated in

populated areas like cities, (b) the field of view will be limited, usually to 60º to 80º and (c) the GNSS/Inertial

Navigation System (INS) is not effective when satellite visibility is obscured by vegetation or buildings.

However, advances in technology allowed these issues to be overcome.

In 2004, a major telecoms company approached 3D Laser Mapping, a company specialising in laser scanning

technology, to investigate the feasibility of a commercially viable system. Fortunately, such a system was

already under consideration by 3DLM and its partner IGI, an engineering company from Germany working in

the surveying market. The system named StreetMapper uses laser scanners which overcome two of the

limitations outlined earlier. The laser scanner was Class 1 eye-safe, had a field of view of 80º and was

reasonably priced thus making the use of multiple scanners financially viable. The remaining problem was to

find an effective GNSS/INS solution for use on the ground while moving.

Some trials were undertaken with a GNSS/INS solution designed for aerial survey applications. In most

situations during aerial surveys, there are no obstructions between the GNSS antenna and the satellite so once

the GNSS receiver has locked onto the satellites in view then the positional accuracy will remain high.

However, on the ground, each tree and building will obscure the view of one or more satellites. This means the

quality of the GNSS solution and thus positional accuracy will vary. A good quality INS system will “bridge the

gaps” in the GNSS solution. Over a short time span, the INS system can accurately record the relative position

of the system to augment the GNSS solution.

At the time, there were a handful of GNSS/INS solutions on the market that are suitable for use on the ground.

Having reviewed the real-world performance of these systems, the IGI Terracontrol (the terrestrial alternative of

IGI’s Aerocontrol) was selected. A key criterion for the INS system was for the accuracy of the trajectory to be

maintained during 120 second duration of poor satellite visibility.

The performance of the Terraccontrol system is illustrated in two charts taken from the survey of the A14

highway in the UK described later on. The first chart (Fig. 1) is the number of satellites in view against time.

This shows clearly where the system has passed under three bridges and no satellites are visible.


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Fig. 1: Number of satellites in view against time.

The second chart (Fig. 2) shows the root mean square (RMS) positional error of the INS system against the

same time period for the first chart. High positional errors can be seen that coincide with the three bridges and

other areas where few satellites are visible. However, the INS has kept the accuracy within 50 mm in elevation

and 38 mm in XY.

Fig. 2: RMS positional error of the INS.

The first StreetMapper system was assembled in mid-2005. Six months of reliability and accuracy testing were

undertaken before delivering the first system to a customer.


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Fig. 3: This image shows an early mobile laser scanning system

(two laser scanners) mounted on top of the large van.

System improvements

Since 2004, mobile laser scanning technology has significantly improved. The introduction of scanners with

360o field of view allowed significantly better field of view and more portability. The GNSS/INS accuracy has

improved, partly through better software techniques and partly through the expansion of the GLONASS satellite

network.

The sensor mounting platform is critical to the success of any mobile laser scanning system. The StreetMapper

360 system uses an innovative lifting sensor platform that has significantly improved the protection of both

equipment and personnel during installation, use and routine maintenance. The scanners are protected from the

weather during operation, and can be removed from sight when not in use. In addition there is no requirement

for personnel to work at height, which can be a significant risk to health and safety.

Fig. 4: Sensor mounting platform for mobile mapping system.

Many users of mobile laser scanning systems will not require a fixed vehicle installation and prefer a portable

system that can be easily mobilised around the world. The StreetMapper Portable system can be transported as

normal checked-in baggage with an airline with two people travelling. This system mounts onto normal roof

bars and is designed so the sensor and IMU can be easily removed when necessary.


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Fig. 5: Roof mounted mobile mapping system.

Miniaturisation

A breakthrough in miniaturisation came in 2014 when Riegl launched its VUX-1 scanner for RPAS applications

weighing only 3,6 kg. It did not take long for customers to start using this scanner for many other applications.

In 2016, the ROBIN system was launched which takes advantage of miniaturisation of the laser scanner, the

navigation system and modern, tiny, high performance data loggers. This system was small enough to allow

usage on a backpack (walking), a vehicle or an aircraft (RPAS or helicopter). For surveyors, this was now a high

performance tool for their toolbox allowing flexibility in many different types of projects.

Fig. 6: ROBIN backpack system.


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Typical ROBIN project: Mam Tor landslide

Mam Tor is a 517 m hill near Castleton in the High Peak of Derbyshire, England. Its name means “mother hill”,

so called because frequent landslips on its eastern face have resulted in a multitude of “mini-hills” beneath it.

These landslips, which are caused by unstable lower layers of shale, also give the hill its alternative name of

Shivering Mountain. The landslide advances at rates of up to 500 mm/year and in 1979, the continual battle to

maintain the A625 road (Sheffield to Chapel-en-le-Frith) on the crumbling eastern side of the hill was lost when

the road officially closed as a through-route. This site represents an ideal example to illustrate the flexibility of a

rapidly deployed backpack mounted laser scanning system.

Fig. 7: Map showing the location of the Mam Tor landslide.

One of the big challenges when assessing landslide stability and damage to local infrastructure is capturing

suitable 3D data for detailed analysis and interpretation. Terrestrial laser scanners have been used at many

landslide locations to capture 3D data, but the often complex terrain means that multiple, time consuming

scanner setups have to be used to minimise gaps in the data. In addition, airborne surveys are typically

expensive and require detailed planning before data can be captured. To overcome these limitations, the ROBIN

backpack system was used at Mam Tor to quickly capture a detailed 3D dataset suitable for mapping

geomorphology and assessing the extent of landslide induced damage to the A625 road.

Fig. 8: Performing the walk-over survey across the damaged road.


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In July 2016, the ROBIN system was used to perform a walk-over survey across the damaged A625 road

surface. The highly mobile and lightweight system enabled easy access to all areas across the site and 500 m

linear section of the road and surrounding terrain was surveyed in approximately 30 minutes. The road surface

has extensive fracturing and there are also large detached blocks with angular faces. These features were easily

captured using the ROBIN as it was possible to walk around the blocks and use the downward facing view of

the scanner to capture the width and depth of fractures.

The highly portable nature of the ROBIN system offers significant advantages for capturing lidar data in

challenging terrain. The case study at Mam Tor highlights the capability to quickly and easily capture accurate,

detailed 3D datasets of a landslide damaged road.

Fig. 9: 3D point cloud of the surveyed area showing detached blocks and fracturing.

Typical ROBIN project: Newark Castle

Heritage sites often have difficult access and irregular shapes so backpack-based mobile laser scanning is ideal

for these applications. The ROBIN was used to survey Newark Castle.

Fig. 10: Newark Castle point cloud surveyed using a ROBIN system.


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Successful commissioning of a mobile laser scanning system

All vendors of mobile laser scanning systems try to make their systems easy to use, however, it is not yet

possible to remove all the complexities from the end user – and ignoring these will leave users disappointed

with the accuracy of the results. Using a GNSS based mobile survey system means that the user’s environment

will have a big impact on the results, so good quality training and support is required.

Having deep insight into the deploying of mobile mapping systems is essential for the accuracy and results of

the project. Therefore there are specific questions that require answers when setting out on a mobile mapping

project.

Do you understand how complex mobile mapping is?

The technology involved in mobile mapping is complex and is not to be understated.

If we analysed the companies which have been successful in deploying mobile mapping we would find they

have all had a “technical champion” on the team who develops a deep understanding of the technology and

mentors the rest of the team. If you have no champion, then the implementation time will take much longer and

this starts to impact project delivery timescales (and return on investment).

It is required to have a technical champion. Having a clear and executable strategy is required with some of the

following aspects:

Review current staff skills and experience. Recommend suitable candidates and propose a specific training

programme for the champion based on their existing skill level.

Assist in recruiting and selecting a champion to be employed by your company.

Assist in locating and selecting locally based independent contractors, who could act as the champion during

the early stages of implementation.

Consider using the supplier’s staff on secondment during the early stages of implementation.

Do you know what specification system you require?

There is a wide choice of mobile mapping systems on the market now. However many vendors have a limited

range of products so it is sometimes the case that your preferred vendor does not have the right specification

system for you. Are you really getting the best advice on what specification system you require?

The following considerations are essential to understand which system is best:

Scanner range performance

Scanner range noise (what resolution objects do you need to see in the data?)

Navigation system accuracy (especially in urban environments)

Camera systems (panoramic or frame cameras? What resolution?)

Mounting to the vehicle (permanent or temporary?)

Portability (do you need to fly to another city to undertake projects there?)

Weather protection for the system (is it necessary, or do you only work in good weather?)

A detailed analysis of the specification that you require for your proposed projects should be done. If there is

any uncertainty, then undertaking a pilot project to see if your analysis is correct and the produced data meets

the set requirements.

Have you considered the whole software workflow?

There are many brilliant software packages available for processing mobile laser scan data. The strategy that

“best of breed” is better than insisting that all software comes from one vendor. (This is in line with the first

point about complexity.) There is no one software package that does everything. However, already running

CAD or GIS software and the results from the mobile mapping needs to end up in the software.


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Analysis of the requirements should be done and a report on recommended software should be written. This will

consider the following issues:

Workflow with analysis of activities and data types

Recommended software (supplied and supported by the chosen supplier)

Recommended software (supplied and supported by other vendors)

Analysis of training requirements

Proposed software budget

Have you budgeted for enough training?

Purchasing a mobile mapping system is a considerable investment and you will need to see a rapid return on

investment. As a result, your staff will be tasked with delivering successful projects as soon as possible.

Are your staff going to have enough skills to deliver projects quickly enough? Have you compared the training

recommendations of different vendors and are you focusing on this as a priority issue in your decision making

criteria?

The minimum requirement for training should be - Phase 1: Basic training of system operation and data

processing and Phase 2: Undertaken 3 weeks later, advanced training and project support for first live projects.

In conjunction with the discussion about the “technical champion”, the following options should be considered:

Training at your location or at the training centre of your supplier

What number of trainees will be on each course? (Normally a maximum of four people)

Will all trainees have a high specification PC and software during the course?

Will training take place ahead of system delivery?

Will further advanced training be undertaken after six months?

Will you get enough technical support?

Insist on speaking to existing clients before selecting a supplier. The number one support issue from all new

mobile mapping customers is considering what geodetic coordinate systems you will be using.

Have you considered the following questions?

Where is the vendors’ “centre of excellence” where the deep level support comes from? Are you able to

contact the support team? Have you met any of them?

What local support is offered and what level of expertise is offered?

What spare parts are needed and how long will it take to get them?

Does the vendor have a standby system available for customers?

Does the company have a “shutdown” for holidays when no support is available?

It is a benefit of having the supplier provide training with the same person that would provide the technical

support. This will ensure that the situational awareness of the client is known to the support engineer.

When do you want to start?

Not many companies can afford to purchase an expensive asset such as a mobile mapping system many months

before fee-earning projects start. This often leads to a rushed delivery and implementation period that is not

beneficial for the long term strategy of company. The best implementations are undertaken over a few months

so staff have time to build up skills and become confident to operate the system (as already mentioned, these are

complex systems).

Avoid rushed deliveries and let your supplier developed a process that works for your needs. This can be

achieved by taking advantage of demo/standby portable mobile mapping systems that can be rapidly deployed to

most countries around the world. Also, consider some of the following options:

Undertake a small fee-paying project with a mobile mapping system before taking delivery of a new system

(or even before making the final decision to purchase). The supplier’s team could operate the system and

process the data in your offices. Your staff will get to see all the steps of a successful project before they

start their own training (and this but the training into context).


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If your team has already taken part in a project, then it will be possible to start the training in advance of the

system delivery. This way they are ready to start as soon as the system arrives.

Identifying, understanding and delivering the required multi-level support

Establishing responsibilities

There is a requirement for the mutual and equal sharing of effort and time by both customer and supplier of the

support. A prepared and discussed RACI chart, that addresses the responsibilities of both parties, across all areas

of support requirements, will be the starting point for the support identification. There must be a balance

between the responsible usage of the technology and the value to the client; and the effort from the supplier to

ensure that the value is consistent and uninterrupted. Feedback loops through effective communication models

are to be agreed and the technology champion, previously mentioned, should be seen as the main contact point.

Mature technology usage as a driver for multi-level support

The usage of the technology should be effective and efficient as a product, the processes that are involved using

the product, as well as the ability and experience of the persons using the product. Thus, the people, process and

technology areas should be supported. There is a strong correlation between mature technology usage, in post-

adoption of the technology, and the perception of usefulness of the technology [2].

Due to the complexity of the products and the various technologies involved, the support for these technologies

are equally complex and therefore require structured platforms of support with clear checkpoints that highlight

deviations from the standard. Scheduled engagement and discussions relating to the mature usage of the product

and technology should drive further skill development and collaboration. This exercise in itself, fosters

relationships between supplier and customer.

Technology: reliable product

The product/technology is maintained with a maintenance schedule that adheres to the manufacturers

requirements for the product. This directly relates to accuracy of the product as well as the longevity and

reliability. Having a product that is consistent in performance is an absolute requirement, in the complex nature

of the technology. There are various ways of ensuring that the product is within the required maintenance

schedules. These are the mechanisms that are used to keep track of the product health and progress through its

lifecycle:

Scheduled visits: Site visits are scheduled to inspect the product and plan the required maintenance. Details

such as hours of use; firmware versions; cabling and accessory status is recorded.

Remote login (using GSM): Using remote login through systems, for periodic health checks on the product

will highlight any possible faults or maintenance requirements. Tests on firmware as well as basic functions

are performed, to ensure that there are no anomalies that may cause a vault.

Process: A effective and efficient processes drive mature technology usage

The processes used to derive value from the technology is set out in initial pre-adoption training. These

processes are re-enforced through scheduled engagement and refresher training.

Process of “best practice” and standard operating procedure: Using checklist to record the adherence to

standard operating procedure, indicates areas of improvement. Sharing industry best practice in basic

functions will save time and increase efficiency.

Sharing advances in effective and efficient process: By sharing advances in the processes, the usability and

relevance of the product is continuously kept up to date.

Remote diagnostics sent back to manufacturer (using Satcom anywhere in the world): Instant feedback on

the health of the product, ensures quick support response and can minimise the impact of any incidents.

People: maximising the use of the technology

The people using the product should be able to effectively and efficiently use the technology to derive maximum

value. This is achieved by understanding the product and the environment in which it operates. Staff churn as


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well as promotion of staff impacts on the end user and the technology champion of the product. It is therefore

imperative that a training regime is kept to ensure full usage of the product. Discussions around the skill matrix

and how to ensure maximum coverage, should address any movement of staff proactively:

Training: Initial and refresher training should be seen as enhancement to the product. This is especially

important in technology that is constantly updating and in itself changing.

Champion identification: Identifying the right person with the correct skillsets to perform in areas that will

enhance the benefit of the product. This could be an area of post processing, which will decrease the time it

takes to deliver the end product.

Communication and feedback

Throughout the support contract, the feedback and reporting of all engagements and findings should be shared

with recommendations. These recommendations should be managed in the form of a project to ensure

implementation and completion. A rating of “Maturity” is derived and presented to the customer and will serve

as a benchmark for improvement in areas of process; product health and the effective usage of the product. This

creates a balanced relationship of input and efforts that can be maintained by:

Steering committee: By establishing a steering committee that convenes at set timeframes, will allow the

discussion of recommendations and highlight any areas that requires focus to ensure optimal use of the

product.

Annual review meetings: This allows management to discuss the performance of the suppliers support efforts

and initiatives, by evaluating reports generated through engagements. Also the performance of the customer

in relation to best practice and processes are discussed to highlight possible improvements.

Collaboration and innovation

The main aim of multi-level world-class support is to create a sustainable and mutually beneficial relationship.

This will enable the collaboration between the parties to innovate new areas of the product as well as enhance

current functions. Clear communication models enable a flow of ideas that will lead to the development and

ultimate enhancement of the product. Driving towards a vested business model that enhances the product

delivers new innovation in the market and stimulates further diversification of the supplier’s offering.

References

[1] M Redstall: “Accurate terrestrial laser scanning from a moving platform”,

Geomatics World, July/August 2006, pp. 28-30.

[2] Elena Karahanna, Detmar W Straub and Norman L Chervany: “Information Technology Adoption Across

Time: A Cross-Sectional Comparison of Pre-Adoption and Post-Adoption Beliefs”, MIS Quarterly,

Vol. 23, No. 2 (June 1999), pp. 183-213 Stable URL: www.jstor.org/stable/249751

Contact Matthew Bester, 3D Laser Mapping, Tel 012 683-8858, [email protected]

http://www.jstor.org/stable/249751

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