Crafting Solutions: The Art of Problem-Centric Software Design


At the heart of problem-centric software design is a desire to understand the complexities of the problem statement. This entails moving beyond surface-level descriptions and immersing oneself in the context of the situation. Whether it’s creating a new app to manage family finances or optimizing logistics for a global supply chain, great software design starts with a thorough understanding of the difficulties at hand.

Key advantages of problem-centric design

One of the key advantages of problem-centric design is its ability to foster innovation. Instead of jumping straight into coding based on assumptions or preconceived notions, developers take the time to conduct thorough research, gather requirements, and engage in meaningful conversations with stakeholders. This deliberate approach often leads to the discovery of novel solutions and inventive ways to tackle complex problems.

The creation of a medical practice scheduling application is a concrete example of problem-centric design in action. Instead of rushing to create a generic calendar solution, the development team will spend time shadowing employees, observing patient flow, and identifying scheduling trouble areas. This hands-on approach uncovered inefficiencies such as double bookings, high wait times, and coordination issues with other departments.

With these findings, the team set out to create a solution that would address these unique issues. This included not just creating user-friendly interfaces and robust backend systems, but also incorporating functionality specific to the needs of the medical practice. For example, the application provided automated appointment reminders, connectivity with electronic health records, and real-time notifications for schedule changes.

Throughout the development process, the emphasis remained on the problem at hand. This entailed obtaining feedback from end users, iterating on designs based on usability testing, and constantly refining the solution to better meet user requirements. By putting the issue front and center, the development team was able to create a scheduling tool that not only met functional needs but also provided concrete benefits in terms of efficiency, productivity, and patient happiness.

However, problem-centric design involves more than just fixing immediate difficulties; it is also about future-proofing solutions to ensure long-term success. In the case of the medical scheduling application, this entailed predicting prospective changes in healthcare regulations, shifting patient expectations, and developing technologies. Building a flexible and modular design allowed the application to easily adapt to new requirements and interface with other systems as needed.


In conclusion, The Art of Problem-Centric Software Design emphasizes the significance of beginning with the problem and allowing it to influence the whole development process. By adopting a pragmatic and user-centric approach, developers may create solutions that not only meet immediate demands but also pave the way for future innovation and growth. The proverb goes, “If you want to build great software, start by solving the right problems.”

Password Management in AV Projects

Password management is a challenge within an audio-visual (AV) project, just as it is for individual households and businesses. AV integrators use default admin passwords to simplify the hardware installation and credential management. But new infrastructure security laws are on the horizon, requiring AV integrators and installers to be more careful with privileged passwords. 

On January 1, 2020, California implemented legislation through Senate Bill 327 that requires a unique preprogrammed password for each device. The UK is working on similar legislation called The Product Security and Telecommunications Infrastructure (PSTI) Bill that will take effect in 2022. Breaking these laws has significant penalties. So, AV integrators should pay attention. 

Unique Password Challenges for AV Integrators 

The new regulations mean that AV Integrators need to make password change management an integral part of the project planning. Integrators and installers have to set up unique passwords and have a reliable way to manage the individual passwords for subsequent administration of the controller boxes and connected AV devices. 

Generally, an installer is the first person to touch an AV controller. But after the setup, the installer should not have visibility of the newly set password. So, AV integrators need a method to set passwords securely for multiple devices. 

But multiple unique passwords create a scalability problem. When AV integrators connect to the hardware remotely for maintenance, they have to factory reset the units and start with default passwords. It can complicate hardware maintenance and become a bottleneck. 

Our approach for More Efficient Password Management 

At Lighting Control, we set up a complex common password for all devices during the commissioning phase of an AV project. We can work faster without dealing with unique passwords at this stage. Then, at the end of the commissioning process, we use scripting tools to improve the security of the systems and add multiple user accounts. 

But if the scripting tools use plain text configuration files, the control passwords and IP configurations are easily accessible. It can become a potential security risk. So, we found that the best solution is to use PowerShell scripts with Active Directory (AD) accounts. As a result, the passwords are encrypted. It ensures that installers and users can run the scripts without accessing the credentials directly. 

We hope our password management best practices help you with your AV projects. If you are interested in our AV products and AV consultancy services, please feel free to contact us today. 

Neil Silver Crestron CSP

Neil Silver

Lead Developer LCD – Crestron Programmer , CSP

Managing the Development and Custom Programming Teams on a day to day basis and responsible for Product Design and Project Oversight.

Interfacing with Technology Trends in Touching Less

Seven years on from the launch of the Amazon Alexa, we are still finding our way into touchless control of hardware and software. Voice technology has matured, and so has our understanding of when and how to use it. Other touchless solutions are now emerging and provide options in many situations. Implementing these new solutions and seeking acceptance and adoption from users is key to the evolution of touchless interfaces. 

The Changing Landscape of Touchless Technology 

Touchless technology allows users to control systems and devices without physical contact. In a post-pandemic world, audio-visual (AV) manufacturers are using existing and new technologies to create solutions that can help people return safely to public facilities like offices, hospitals, schools, hotels, and restaurants. The 2020 estimate for the gesture recognition and touchless sensing market was around 23.6 billion US dollars. 

Like AV manufacturers, AV system integrators are also thinking creatively. Integrators are combining multiple technologies to create more holistic solutions for their clients. They are designing touchless systems to automate door access, control meeting room equipment, and manage lighting, video, and digital signage.  

Here are a few noticeable trends in touchless experiences: 

QR Code and BYOD Control Apps 

Shared screens, buttons, and remote controls are popular control mechanisms for building management systems. But shared devices spread germs, and they are vulnerable to vandalism, theft, and displacement. So, AV manufacturers and system integrators are harnessing the power of QR codes, custom apps, and bring-your-own-device (BYOD) philosophy to build touchless AV systems. These systems require minimal infrastructure investment.  

Mobile apps, phone cameras, and wearable devices are replacing shared control devices. For example, A QR code can be placed in the room in printed form and displayed on one of the screens. Users can download an app on their devices and scan the QR code to gain control of the meeting room equipment. It eliminates the need for touching the equipment controls to activate the screens, microphones, and cameras. Crestron One and Atlona Velocity are examples of QR-based BYOD control. 

Touchless Access Control 

Public facilities require access control for physical and digital security. But keycard-based access control adds a lot of bureaucracy. Issuing keycards to employees and visitors takes up time and resources. 

Mobile app-based access control systems are faster and more efficient. Multifamily, commercial, and office spaces can use the apps to issue visitor permits, log visitation information, and track arrivals and departures. The systems can be enhanced using face recognition technology. A robust software-based access control solution automates the processes and decreases security errors. No more dangling keycards that someone forgot to deactivate. 

Voice-Controlled Scheduling Systems 

Digital assistants like Amazon Alexa and Google Home are crossing over to commercial applications. Businesses are using these voice technologies to install AV systems that respond to scheduling requests. Whether users want to book a conference room or connect to a remote location during a meeting, voice assistants are becoming part of modern enterprise infrastructure. AV Integrators are installing voice controllers in conference rooms and shared public spaces. The no-touch automation of scheduling tasks is providing a better user experience for AV customers. 

AirPlay for Touchless Content Sharing 

Apple AirPlay has made video streaming, screen mirroring, and file sharing easier over wireless connections. Meeting attendants can share content without using a dongle or a wired device. Also, users are already acquainted with the AirPlay user interface. So, familiarity has led to more customers using touchless content sharing.  

For AV integrators, wireless and touchless content sharing has simplified equipment installation and maintenance. Integrators have fewer wired connections and proprietary software to consider. It has decreased their workloads and freed up resources. 

Evolution of Audio Control with Alexa and Other Voice Assistants 

Voice assistants like Amazon Alexa and Google Home are becoming central control systems for enterprises and small businesses. Voice assistants started as simple audio search engines, and they were initially useful only for digital information queries. But, they have entered the realm of the physical world with the help of the Internet of Things (IoT). 

Today voice assistants have become a crucial part of controlling smart homes and offices. With voice assistants, users can control lighting, elevators, conferencing systems, digital displays, security cameras, door locks, and more. Voice technology providers let organizations integrate custom AV control systems through application programming interfaces (APIs) and software development kits (SDKs). 

The Impact of Voice Assistants In the Professional AV Environment 

For AV integrators, voice technology has changed the design, installation, and implementation of AV systems. Initially, AV integrators assumed voice assistant integration would require more proprietary hardware and software installations. However, as the technology matures and more wireless and IoT-based solutions come into the market, voice assistant technology makes AV integration easier.  

AV manufacturers are using Amazon Alexa, Google Home, and Google Nest as an integral part of their design. It is leading to more standardized solutions and opening new opportunities. AV integrators can use the standard APIs and SDKs to design customized solutions compatible with multiple AV vendors. 

Touchless Solutions for Assistive Technology 

A side benefit of touchless user interfaces is that the solutions provide more accessibility. Disabled people can use voice-activated controls to open doors, turn on lights, or activate and control AV equipment. 

The Future of Touchless Solutions 

Touchless technology has come a long way. But it is still an evolving field. New and exciting developments are already on the horizon. Here are a few things that might be interesting: 

  • Motion Capture and Gesture Recognition: Advanced motion sensors will make it easier to control AV environments without any additional control devices. It might remove the necessity for BYOD devices. Combining voice recognition, face recognition, and gesture control will make the new systems true touchless experiences. 
  • Mind-Controlled Interface: Scientists are developing brain-computer interfaces. These interfaces will allow users to issue commands without using voice technology. It will open new avenues for no-touch applications. 
  • Haptic Interface: A challenge of using touchless technology is the absence of touch. Our brains have a difficult time understanding objects without tactile sensations. Haptic interface generates the feeling of touch, allowing users to manipulate objects more accurately. Imagine drawing on-screen using your fingers and having more tactile feedback during the process. 

Touchless technology has already transformed the AV industry, and we can expect more innovations to bring better solutions in the future. If you want to learn more about implementing touchless technology and our consultancy services, please feel free to contact us today. 

Crowne plaza – Glasgow

Crowne Plaza Glasgow

Lighting controls undertook the programming and  commissioning of the recently refurbished Argyll and Castle conference suites at the Crowne Plaza Glasgow.

Both large Suites have multiple partitions to allow the rooms to be used in different configurations.  Mode evolution packs were used in combination with Key switch plates to provide intuitive functionality. This allows members of staff to recall specific lighting scenes dependant on any room configuration.

Argyle Suite

Argyle Suite

Lighting Control System Standards


This short document aims to present the common Lighting Control System Standards used in the lighting industry today and give a short explanation of their development, uses, advantages and disadvantages.


Lighting can be switched on or of and it can be dimmed that is the light output of the lighting source varied to different levels in between off (no light ) and full on ( the maximum light output of the source)

Electrical Dimming

When halogen lighting is in use the dimming is simple and can be carried out either remotely or locally. A dimmer of this type (for a halogen load) achieves the dimming by reducing or increasing the level of the r.m.s. voltage and hence the average power.

Traditional Triac or thyristor dimmers use switching techniques to achieve this varying voltage. Inductors are the other main component of the dimming circuit and these are used to suppress interference caused by the switching. When a dimmer is at 50% they are switching the greatest voltage and the interference in the circuit is at its maximum. This is the cause of the vibration in the inductors that causes a buzz to be heard near to the dimming units. The inductors add weight to the dimmers and the suppression provided is often not sufficient to prevent the buzzing being heard on audio systems that share a closely related power supply.

Although the most simple form of dimming this type of dimming is not without it’s problems:

Low voltage lighting is now in very frequent use in projects using a wirewound or electronic transformer to provide a 12 v voltage for the lamps.

Traditional wirewound transformers provide an inductive load to the dimmer and the current of the load lags behind the voltage. Once triggered a triac requires the flow of current to the load through the device to maintain its operation. When the current falls below this threshold the device will switch off. If the current lag from an inductive load is sufficient the current flow in the circuit will not reach a sufficient level to maintain the triac and the device will turn off givingflashing and unwanted effects.

To avoid this effect the length of firing pulse on the dimmer can be varied to last long enough for the current to ‘catch up’ .

When using electronic dimmers only dimmers designed for use with a dimmer should be used although others may work they will not work for long.

Electronic Dimming

Electronic ballasts

Fluorescent and High intensity discharge lamps are frequently used in both residential and commercial projects. These use electronic ballasts to provide the supply to the lamp or lamps. Electronic ballasts usually change the frequency of the power from the standard mains (e.g., 50 Hz in uk) frequency to 20,000 Hz or higher, substantially eliminating the stroboscopic effect of flicker (100 or 120 Hz, twice the line frequency) associated with fluorescent lighting (see photosensitive epilepsy). These devices are often based on SMPS topology and allow dimming via pulse width modulation.

Generally these ballasts will be permanently connected to a mains power supply and also have one set of control connections either two or three core dependant on the type of control.

LED Electronic controllers

Led lighting is more and more popular due to the energy efficiency and the colour change possibilities without the need for filters.

LED units are however more complicated to dim than halogens. Dimming using a traditional dimmer above at best will not work and at worst will cause damage to your control gear and your dimmer.

Electronic controller specifically designed for controlling LED’s exists in both single channel devices and most commonly in three or four channel devices to accommodate colour change.

These devices provide a constant current supply to the LED and vary this supply using pulse width modulation to lower the duty cycle of the led and create a dimming effect.

These devices come in many shapes and sizes depending on what you wish to control. They also come as either integral units with LED power supplies or stand alone units which are connected in conjunction with and LED power supply.

Control either local or remote and if remote using 0-10V DC, DMXgenerally.

Cold Cathode Electronic controllers

The term Cold cathode is usually used to describe concealed lighting in coffers of cornices and is often used as an indirect up lighter. The name is in fact a description of the technology (fluorescent lighting for example is known as hot cathode). Cold cathode tubes are usually divided into two groups, those filled with Neon (red) gas and those filled with Argon (blue gas). The range of colours available is created by the use of different phosphors on the inside of the tubes which react with the ionized gases and emit the particular colour light.

Lighting Control System Standards –

0-10v DC (also described as analogue)

The most basic of these control signals is 0-10V DC (the same as is used as the basis of most Triac dimming systems!) However small electronic ballasts are always located locally to the fitting and hence the DC control pair must travel from the processor to the fitting and may be susceptible to interference.


·Simple to wire and understand

·Simple to test with simple test equipment


·Most common fault is inverted +/- wiring

·Susceptible to noise

DSI – Digital Serial Interface

DSI is a digital protocol for controlling lighting in permanent installations. The standard uses uses a single byte to communicate the lighting level ( 0-255 or 0x00-0xFF).

In a DSI system each lantern or group of lanterns has it’s own control cable running from the processor or controller. There is no addressing of lanterns to be set.


·Simple to wire .

·Relatively simple to test with relatively simple test equipment


·Large systems have many control pairs running back to central system

·Initially a proprietary standard exclusive to Tridonic

DMX-512 –Digital Multiplex

DMX is a well know control protocol based on RS485 standard. The standard was developed for use in the entertainment industry to control multiway dimmers and intelligent lighting. Until recently the standard was never used in construction applications however due to the advent of RGB LED and cold cathode systems requiring more detailed control DMX has become the protocol of choice in these situations.

A DMX512 controller is connected to fixtures or devices in a multi-drop bus topology commonly called a “daisy chain”. 512 fixture attributes can be controlled on each DMX universe and if control of more is required additional universes can be added.

A fixture attribute may be a single channel of a dimmer.

Or a single colour on an RGB LED controller.

Fixtures are addressed using a menu structure or DIL switches. If a device has multiple fixture attributes such as a 12 channel dimmer, a 3 channel LED driver or a 32 channel intelligent light then the address of the channels first fixture will be set and the following channels will follow in sequence.

e.g. a 3 channel LED driver with starting address 1 will use

ØChannel 1 Red

ØChannel 2 Green

ØChannel 3 Blue

Channel 4 and onwards are “free” to use for other fittings.

Many devices utilize automatic addressing and while this has it’s place for certain applications I must say that from experience I am not a fan.


·Strict adherence to the daisy chain topology must be followed (no Y-splits).

·Allows very accurate control.

·Long distances are possible even without buffers.



·Specific shielded cable must be used CAT 5/6 is not suitable.

·Difficult to fault find at signal level

DALI – Digital addressable Lighting Interface

DALI is and open standard protocol introduced as a rival to DSI and a successor to 0-10V control systems which still dominate the industry. The protocol allows control over a number of fittings using bi-directional data exchange over single bus with a maximum of 64 devices.

Devices are addressed individually and in addition to allowing control over the device feedback is provided to the system giving status of the device.

DALI has group and scene commands as part of the protocol allowing the reduction of data traffic and reduced network latency.


·Simple to wire – It requires only a pair of wire to form the bus connecting all devices on a single DALI network.

·Relatively simple to carry out basic tests with relatively simple test equipment

·No topology restrictions STAR and T’s are OK!


·The limiting factor of 64 addresses is not enough for large installations.

·Difficult and expensive to test and fault find

·Speed of the system (1200 bits per second ) can mean visible delay in larger installations

Copyright Neil Silver Lighting Control 2007

Neil Silver is the Technical Director of Lighting Control. He carries out a wide range of design and programming work in both commercial and domestic lighting controls systems.

Lighting controls and design

I visit many high end developments programming lighting controls. When we are just contracted to do the programming we arrive on site after all the first fixing has been completed and sometimes even later than that at a very late stage when the project is near to completion.

You can understand control panels for a lighting control system being placed in the traditional spot near the entry exit point of the room. I don’t think this is the future of lighting control and comes from the old technology of electric light switches but that is fordifferent rant!

On many of these sites I find Audio Visual control panels in the same place at the entry exit point of the room.

When I was 16 I bought myself a simple Sony Midi System ( CD , Tuner ,Cassette ) with a simple remote control. This allowed me my first glimpse into luxury control!!

From the comfort of my bed or from my easy chair or indeed from my computer desk I could quickly and simply control my music for the room from each location. Not rocket science I hear you say but really effective simple control.

Move forward fifteen years and you would think that the intervening years would have moved us forward especially with a large budget on a multi-room penthouse project.

However even with a well known control system and a huge budget the control in the bedrooms of theses projects have arguably a less flexible and overall a lower overall standard of control than my bedroom did fifteen years ago.

Why ?

Who does the design of these projects ?

(I often find myself asking mostly under my breath). There are generally three different answers; The Salesperson of the control system told us to put them next to the light switches, The Electrician or developer who had no drawings had to make the decision and went with what they know, The Lighting Designer or architect who spent hours of quality work on the fixture placement and selection and did the controls as an after thought.

Am I being a bit harsh on all these individuals?

The Salesperson should not be doing the design of the lighting or of the controls. For one thing if a salesperson designs anything they will always design with a bias to their products which may not be the best solution. Design is an involved process that requires interaction with other design professionals involved who a sales person generally does not have access to.

The Electrician who does not have a drawing goes back to what they know. Electricians are trained in electrical system design. This design is design of systems to comply with the wiring regulations and the training does not extend to anything but simple positioning of items for ease of use. If I am being really harsh the level of training for lighting given to most electricians is limited to two-way switching with a number of sparks struggling with an intermediate. In fairness as well a building site with deadlines and other contractors is no place to be making cool calculated design decisions.

Lastly there is our Architect or Lighting designer who as I said has spent hours of time making a really great (hopefully) lighting design for the project. On a number of occasions that’s where they stop. The Drawings are produced with no thought to lighting controls and design whatsoever. On many occasions the design is produced with no thought to maximum loadings of control gear which is really unforgivable but I would say that not thought to lighting control is equally wrong. In this article today I’m only talking about the relatively simple design decision of placement of controls not even looking at the next stage of what these controls do and how they interact with other control in different positions. The limit for most designers is to write a multi-scene scene setting for a system in the form of a table giving circuit numbers and relative intensities. On the placement of the controls the designers all seem to have been to the same training as the electricians and cannot bring themselves to look out of the box and try and make the design better. Architects and designers talk about movement of users through a design as a very important concept in the design process. In the modern automated house the movement of individuals is dictated by control of the lighting and audio visual systems within the space and should hence get a healthy proportion of attention from professionals with suitable understanding in controls at the design stage.

Lighting controls can serve many purposes. In a commercial project they can ensure that the designers vision is maintained night after night, year after year hence realising the value of the design work maintaining the “look” In this application the placement of controls is usually quite simple but I still see horrific examples of getting it wrong. In Domestic properties the placement of controls is much more complicated. Modern designs involve open plan areas with many entry and exit points within large open spaces. The solution given is often to throw loads of controllers at these points and have them all providing the same functionality.

Neil Silver is the Technical Director of Lighting Control

He is an Electrical and Electronic Engineer with many years experience in controls, Audio Visual and Lighting Systems

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