The Back Room

If you’ve never developed a touch screen application before, there’s a lot to think about that makes it different from a browser based or native application. It’s impossible to go through the full breadth of things to consider, but I figured posting a few helpful tips might be good.

Well Spaced and Big Button Sensing Areas
So, this does not necessarily mean giant buttons. Often that’s a good solution, since museum visitors are not just those familiar with computers but include many folks who don’t interact daily with computers. Really though, it’s about making sure that the sensing areas of buttons are forgiving enough to work with clumsy fingers, and to account for the different alignment people will get from looking at the screen from different angles. If you touch a screen from a low angle on what you see as the button area, and then change your perspective, that button area can be drastically different from above. A mouse is absolute. The button is the button. But with a fingers on a large screen, it can actually chance. So, large sensing areas for the buttons, and don’t put them too close together to account for different perspectives and clumsy fingers.

Consider Hand Position
When using a touch screen, a person uses their hand, thus creating a natural block for some of the screen area. With a mouse pointer, it’s small enough that unless an interface is very tiny, it won’t block anything when using it to select menu items, etc. But, with a finger, you’ve got a whole hand attached. So, imagine you have a screen where you have 5 buttons. Each button makes a change to a large image in the center of the screen. Although many web pages have navigation and other items at the top, this makes little sense in our scenario, because you want to see how your selection is changing the screen. If the buttons are at the top, you’ll have to move your hand away each time you press one to see the results. It may make more sense to place buttons along the bottom, or the right side. Although it may seem biased, you have to consider that most people are right handed, and if you have to favor one or the other, then choose right. The main thing to get from this one is just to think about where people’s hands are going to be and if they’ll be blocking items you need them to see when operating the screen.

Choose the Best Viewing Angle
This has more to do with fabrication than the software programming. You should make sure you consider who the audience is when choosing what angle and height to put the screen at. It seems like a basic enough idea, but there are many times when we haven’t been involved in the hardware or installation decisions of an institution, and they’ve installed a touch screen for children flat on a table that’s 36 inches high. How can a kid see that properly without standing on something? Or, a kiosk is supposed to take a photo of a person to put on postcard and email home, yet the camera is pointing almost at the floor, so if you’re over 3 feet tall, you’re bending awkwardly and contorting to get in the picture. Little things like this really affect the usability of a screen.

Hide the Mouse
I really don’t understand museum exhibits that have mice showing. I think people leave it there so that you see where you’re clicking and navigating. The thing is, you don’t want people to walk up to a touchscreen and see it as just a computer program running. You want them to walk up and see it as an experience that is something they can’t get at home. You can click on buttons at home, but you can’t touch a screen and move elements around the same way you can on a touch screen. Having the mouse pointer on screen breaks up your interface and reminds people they’re just looking at a computer screen.

Give Clear Direction
An interface must give users clear direction about what to do. Children will walk up to an exhibit and start banging away on the screen and they’ll figure it out. It’s the visitors that are new to touch screens and computer interactive programs that will just stand and stare at the screen, not sure what to do next. Things need to be clearly defined, and text must be readable. Sure, many people won’t read the directions, not matter how much you highlight them, but they need to be able to understand what to do by visual clues. There is a lot that can be written about creating touch screen interfaces, but my overall comment here is make sure people understand what to do.

I’m open to suggestions here, and I am not saying my comments are the be-all and end-all, but we’ve certainly learned a lot from working in this area for years. Some other miscellaneous items to consider:

- There are no rollOver or rollOut commands. Tooltips, highlights, etc. won’t work since it’s just about single touches.
- It’s good to use high contrast colors to make sure it’s visible to as many people as possible
- Choose a type of touch screen technology that works for what you need. (Capacitive, Resistive, SAW, etc.)

Anyone else have any tips?

One of the major components of many interactive exhibits is a touch screen.  We routinely work with a variety of touch screen types and technologies at Boston Productions.  Without firsthand experience it is difficult to know which technology works best for a given situation.  The process of purchasing and implementing a screen that will be used by thousands of people a day is also a bit of a mystery unless you have done it before.  You’re in luck because I am going to provide a firsthand overview of each technology I have worked with and common mistakes made while implementing them.

About Purchasing Touch Screens

Usually the big monitor manufacturers such as NEC and Samsung don’t actually make touch aware systems.  When purchasing touch monitors you usually buy them from a company that purchases a monitor and modifies it by adding touch capability after the fact.  This adds to the complexity of purchasing because you need to make sure that you are initially getting a good monitor, but are also working with a competent touch screen integrator.

The Types of Touch Systems

Capacitive – Capacitive touch screens work by sensing small changes in the electrical pattern over the touch screen surface. Your skin creates small electrical connections, and the touch screen software can interpret these to know exactly where your finger is located. Skin, or another conductive material is needed to make capacitive screens work properly. Using a stylus or other pointing device will not work. For instance, the iPhone touch screen is a capacitive screen.

Resistive - Resistive touch screen work by sensing any pressure by any object. It contains a couple layers of sensors and materials. There is a thin layer of a similar material that is the main part of the capacitive screen. It will detect small connections made when contacted by a conductive material. In this screen though, there is another layer of this conductive material that is very thinly separated from the capacitive layer. By touching the screen, you’re pressing down to create contact between the layers, and registering a touch with the computer. Many devices that use a stylus are resistive screens like the bottom screen of a Nintendo DS, or Palm handheld devices.

SAW – Surface acoustic wave is based on sound waves traveling across the surface of the touch screen.  When they are disrupted, the sensors know where you have touched.  For the programmer, a SAW screen can emulate a mouse just like you would expect it to. The SAW technology is what we prefer and use on most of our systems.

Infrared – Infrared is usually based on IR LED’s close to the surface of the screen coupled with cameras that can detect where the IR beams are being disrupted.  You normally can purchase an IR overlay as a completely separate piece of equipment from your monitor and install it on site. These are commonly used on larger screens where other technologies become less accurate. For instance, making a capacitive screen that is 40 inches is very difficult, so often an IR overlay is used. Often, this detects when a finger or other object breaks the plane of the IR beans, so you can sometimes operate an IR screen without actually ever touching the screen.

DST – Dispersive signal technology is based on sensing changes in the mechanical energy happening on the surface of the screen.  You can touch the screen and it will recognize it as a click, but if you continue to hold your finger down, without moving, this type of overlay will think you are no longer touching it.
An advantage of this technology is you can have items already sitting on it, and if they remain stationary; touch functionality will be unaffected for the rest of the screen.  This situation works best for touch screens that are integrated into work surfaces that you could benefit from allowing stationary items to rest on the screen.
Remember that with this technology it is not possible to accurately or consistently touch and hold items while remaining stationary.

Implementation

Although they may seem very similar, each type of technology requires different care and consideration when implementing.

General Considerations

Proper ventilation is always needed when using touch screens.  You will often find that when a monitor overheats you lose touch intermittently or altogether.  This usually means purchasing 80mm fans and installing them in your monitor enclosure.

Be very careful with the bezels of monitors and area directly around the touch surface.  We routinely work with fabricators that love to cover up the bezels of a touch monitor.  When this happens it’s imperative that these covers are not putting pressure on the bezel of a touch screen, or are physically contacting the touch surface.  When this happens you normally end up with a non functioning touch screen.

If covering the IR sensor for a monitors’ remote, have the fabricator drill a small hole so your remote does not become useless.  It’s always handy to be able to use the remote even with a touch screen.

Technology Specific Considerations

DST – In my experience with DST, I worked on several large monitors that were to be mounted vertically.  Due to the way that DST works, you have to be extremely careful when mounting

the monitor not to put any pressure on the screen or bezel.  Because it works based on mechanical energy, if you apply pressure from your mount on one area of the screen more then another, your touch overlay will become biased in one direction.  The result of this biasing is that you have a touch overlay that is more sensitive in one area then the other, or completely unusable.

SAW – Just make sure that you don’t have anything else touching the overlay when you implement it.  Also make sure to clean the monitor surface semi-regularly.

Infrared – With infrared, just make sure you don’t have debris blocking any portion of the IR LEDs or their associated cameras’.  An example of a debris that is pretty common is packing material.  If using an external overlay that you strap to the monitor, make sure that the overlay is very snug against the side edges of the monitor so that it will not move when mounted.  Many external IR overlays can conceptually be imagined as a picture frame.

This is meant as a brief overview of touchscreen technology, and a starting point when trying to determine which type of screen is right for you.

I just wanted to put something brief about this because I’m a big fan. Smithsonian Magazine is sponsoring “Museum Day 2009″. There are hundreds of museums around the country that will allow free entry if you arrive with a printed form downloaded from the magazine’s web site. Participating museums are here. As museum fans here, we really appreciate this sort of thing, and encourage people to head out to see something new.

This is the second part of my article about the pros and cons of the use of a control room for exhibit hardware vs. having hardware on the exhibit floor in cabinets at each exhibit. Read part I first if you haven’t yet. This portion focuses on the distributed hardware option, where each exhibit runs from hardware in a cabinet in close proximity to the exhibits they control, without a central control room.

Strengths
There are some strengths to this approach. It can be much more cost effective in both installation, and the amount of physical equipment actually required. You don’t need any sort of cable extensions to get a signal over a long distance, you don’t need a keyboard/video/mouse switch (KVM) and you don’t need any sort of remote monitors to be able to see what exhibits are doing when you’re not near them. You also don’t need the manpower to install long cable runs and test them. Often, this solution is more easily managed by the institution’s staff, since all the equipment is pretty familiar, since it doesn’t have a lot of specialty gear that would be used in a control-room scenario.

Adding a new exhibit is simplified, since you don’t have to integrate into an existing system. A new cabinet can be built and the hardware placed inside it without having to disturb the current hardware setup that may already be running in another room. It’s easier for other vendors, since they can just focus on installing their one exhibit and not breaking the whole system by what they do.

The maintenance can be easier at times, since if you’re working on any aspect that involves needing to be able to interact with the hardware to test, you don’t need two people. If you need to check a touch screen, pull a lever, or whatever, you can quickly do that while also having access to the computer itself. If you had to run back and forth from a control room, it could take four times as long if you don’t have another person there.

Distributing the power to hardware across the entire institution can be a good idea. It means that if there are any power problems with one of the exhibits, all the AV does not go down together. Similarly, from a security perspective, not all exhibits can be accessed in one place, so any vandal or mischief maker can’t affect the whole institution at once.

Weaknesses
A big weakness to having the hardware spread out across the whole institution is that it is very difficult to install any sort of control system, like AMX, or networking. If you do have those things, then you’re creating a hybrid of the two systems, with some sort of control area, with cables running out to the floor for control and networking. This combines some of the weakest parts of each solution. So, if you want to implement any sort of control system to turn things on and off, vary volume universally, or anything like that, distributing the systems on the floor is a very bad idea.

Updating is a bit more difficult as you have to open each cabinet up and manually install new programs, whether on a computer or a hardware playback device. What might be done in two minutes with a networked group of computers will now take much longer and involve traveling around the museum floor with a thumb drive and potentially a keyboard and mouse to plug into each CPU to get the job done.

Another big issue with this approach is that often, you need to have a cabinet door open and be in plain view of the visitors in order to work on anything. Just adjusting the volume of a computer would involve opening the cabinet. This is unsightly and can be a safety issue if you have wires hanging out or small spaces where children could crawl into. It’s an area that needs to be supervised all the time. If you’re working on an exhibit from a control room during business hours, a small “out of order” sign is all that is needed.

Each exhibit would also need its own dedicated hardware to run. There isn’t an opportunity to use playback devices for multiple exhibits with any ease. So, each video program would need its own player. This may have to be the case anyway, but using this method will almost demand it. Again, you could start to run cabling from one area to another, but you’re going to need conduit, and some clean entries into other exhibit areas.  This drives some costs up, which might have been the ones you were trying to save by going this route in the first place.

So, those are my thoughts on these strategies. There are many institutions that use each way, and some use a combination to do what they do. I prefer the control room, but that may not work for all buildings and costs. Each establishment needs to consider what works for them. Perhaps the extra money that would go into a control room would be better spent making an additional piece or media, or a large facility will have a limited IT staff, so having a central area is important. Either way, try to consider all the aspects of your project before you make a choice. Anyone have any horror stories of either solution? We’d love to hear about it.

Something we’ve experienced both sides of recently is the decision to either create a “Control Room” for your museum AV hardware, or to place each piece of hardware on the floor and hidden in a cabinet or behind walls. People may not be familiar with the different strategies, so I’ll try to explain each as much as I can. Each has its benefits and weaknesses, so I thought it would be helpful to talk about the effects of each approach. Realistically, I could probably write 10 pages on the pros and cons, but this will just be a more concise overview. Part one is about the Control Room.

Strengths
There are some main strengths to having a central control room for AV hardware. The first is that it centralizes the systems so that the installation, maintenance, and basic troubleshooting can be done in one place. If you plan on having some sort of control system for the museum like AMX that will turn systems on and off, it needs to live somewhere, and access is much easier if it’s in one place. Centralizing the hardware also allows you to go to one location and learn the status of all the different systems in your institution. You can look at videos playing, interactive computers, and see or hear audio programs. If all the building’s amplifiers are there, then they are easily adjusted at once, although you’ll need someone on the floor with a walkie-talkie to report back to you.

If there are problems with exhibit hardware, it can be remedied without having to open up a cabinet or door upstairs, rather by working through it in a private area. Although a video might not be playing, visitors would not see an open cabinet, wires, and you poking and testing hardware. This is especially important when dealing with computer interactives. Having a central Keyboard/Video/Mouse switch (KVM) allows you to access all the computers from one terminal with a single keyboard and mouse. If each were in its own cabinet, it would need a keyboard and mouse at each station. If there was a problem, a technician would have to open up that cabinet, pull out the keyboard and mouse, and use the exhibit monitor to troubleshoot. With a control room, the KVM can do that out of visitor’s sight, and be much more efficient for troubleshooting, updating, etc., the computer systems. Having them all networked will also dramatically decrease the time it takes to load new software, transfer files, and monitor the systems.

With all the hardware in one place, there are things that can be consolidated that might otherwise need separate components. This could be especially important when it comes to temperature control, as it’s easy to have one room with good AC. It might be more difficult if you have to install cooling mechanisms in every cabinet that has a computer generating heat. If you’re using some sort of hardware video playback device, like an Alcorn McBride Binloop, you could have one unit with several channels in it that might run 7 different exhibits. If each exhibit were an island, then it would require 7 separate players, costing more. There could be lower maintenance costs as well, since equipment is easily accessed and quickly troubleshot.

Weaknesses
One of the larger strikes against a central control room is the upfront cost in time and money. It requires more equipment like signal extenders for video and touch screens, racks, additional cables, additional video monitors to mirror the ones in the exhibit, and a KVM. Also, it requires more labor to install, since all that cable needs to be pulled, terminated, and checked. This takes more time and man hours, so will cost more up front. Also, the long cable runs have many more failure points that take longer to troubleshoot during installation. But, what’s lost up front is made back in the ease of maintenance of a control room. It might be hard to put a dollar figure on it, but being able to assess the state of the hardware in your institution quickly and solve problems from a central location can save a lot of time and aggravation in the end.

Expandability is hampered a bit, since adding new exhibits would involve running new cable through conduit, the extra hardware to extend it, and making sure there is available rack space. It’s possible to have later exhibits not use the room, but that creates confusion about what equipment is where, and makes the maintenance that much more difficult. Having all the equipment in one place also makes a problem more likely to affect the entire system, rather than just one exhibit. If there’s a power problem in that room, then it could cause all the AV systems in the institution to go down. Local problems in this one area cause systemwide issues.

Perhaps this is something that most places don’t have to deal with, but there is a danger to having all the hardware accessible at once. If someone were to get into this room, he or she could easily bring down the whole place by unplugging stuff, pulling cables, etc. That’s why it’s especially important to keep this room secure and monitored.

I’ll post the rest of my thoughts on this, as well as the pros and cons of putting the museum exhibit hardware on the floor in their own cabinets and areas, in the next week or so.

As Charles and I have been posting about the projects that we’re working on, we realized that there is no one place to go to find out what each exhibit looks like and is supposed to do. So, we’ve added an area where you can look at a list of many of the projects that we’ve worked on. It’s not totally complete, but should be a good place to go if you’re wondering what technology we’re using for each one, and what it looks like once installed.

Also, I realize that there is no real contact page on our site here, and so the best way to contact us is to comment on a post. We may put up a page with a form you can fill out or something, but if you’re trying to contact our company, you can do that by calling 781-255-1555.

Most interactive exhibits in the museum world are programmed on Windows PCs, and there are a few reasons for that. Cost is a big one, since if you want a standalone Mac with dual screen capability, you need to buy a MacPro, which is going to cost you at least $2499. Sure, the $700 PC is going to do less, but you don’t need it to do everything the Mac does. There is no stripped down Mac that can do what we need and a Mac Mini is just not enough power and has very little (basically no) expandability. There are also issues with some touch screens, external devices that need serial ports, and other logistical issues that go along with PCs being the main delivery medium for museums. Another consideration is that wherever you are installing these systems, the local IT folks are going to have to be able to support it on some level. Even if we, as the hardware company, are going to warranty the computers and be available for service calls, the local folks are going to need to be able to configure the machine into their network security policy, understand some basic troubleshooting, and not have to learn a whole new OS to do that. When it comes down to it, most museums, zoos, etc. use PCs, especially if they are associated with the local or federal government.

If we are installing computer systems to run interactive exhibits at a museum, all it takes is one of them to need a capability that only comes on a PC, and that would also dictate that they all are going to be PCs. There is really no option to use an alternative such as Linux either, since most folks out there are not familiar with the OS, there are not touch screen drivers, we use the Flash IDE for much of our stuff and don’t want to rely on Flex since we have some complicated interfaces we don’t want to build entirely with code. These are just a few reasons, but there are many more. When it comes down to it, it’s the most practical, cost effective solution to use Windows PCs in the museum world. I am sure there are the computer professionals out there who will disagree, but I can’t see us moving to Mac development for our interactive programs anytime in the near future.

I use the Mac OS for most of my personal stuff, as well as dealing with work organization, email, etc. My main programming computer is a Dell running Windows Vista, which I do the heavy duty coding, etc. on. I am pretty happy with the setup, and I can’t imagine that I would be able to ever move to one platform exclusively.

I prefer the Mac for dealing with my personal photo stuff, email, video chatting with my family, etc. It’s just easy and I don’t have to jump through hoops. I am thinking about this because the hard drive on my MacBook Pro died yesterday. It happened very fast, with a slight clicking sound that quickly elevated to a loud clicking sound and no response from the computer. I have most of the stuff backed up, although I did lose some recent photos, so it’s not too big a deal. But, I am without my Mac for a few days while they put a new hard drive in, so I have to use my PC for everything here at the office. Of course, I am prepared to do that with a few open source programs. I use Thunderbird for my mail, Pidgin for chatting (so much better than AOL since it has to ads, extra software, etc, and Firefox with XMarks (formerly Foxmarks) to sync my bookmarks. So, on my PC now, I have all my bookmarks, mail, chat lists, etc. ready to go and can work seamlessly from here while waiting for the laptop to come back.

You may be wondering, why don’t you just use all that stuff on your one computer to start with? When I am programming and doing work that takes focus, etc. I don’t want other distractions to deal with. I don’t want new emails popping up, chat screens, or the temptation to check out my RSS feeds (which I keep in the Mac mail client). Also, I do need to be mobile at times, so it makes more sense to keep that stuff on the computer I might have with me. I’ll snap some photos of my workspace when I get the Mac back and I don’t just have a big empty monitor to my left.

More and more, a request we are getting here at Boston Productions is to create content that visitors can interact with at home, thereby extending the experience they have had at a museum. Often, this comes in the form of emailing some sort of creation that was made during a visit, and can be retrieved at home. At The Hershey Story, users can email both a photo of themselves on the front page of a vintage newspaper, as well as create a Hershey’s bar wrapper and send that home to be printed and wrapped around a 4 oz. bar. For both of these experiences, we created not an email with an image attached to it, but instead a customizable email with information about The Hershey Story, and a link to the web site to retrieve what the visitor created. The content can be clicked on and downloaded, and now the user is at the web site, free to explore information about upcoming events, membership opportunities and the latest news.

This may seem like a small thing, but since The Hershey Story opened, thousands of emails have been sent to folks with many of them following the link and ending up at the web site. It’s not as invasive as putting them on a mailing list, which is impossible for many since they are under the age of 13 and would need consent, but still creates a connection with the web presence of the institution.

Other opportunities with this method include adding links for Facebook or Twitter on the page that the items are retrieved from, which would provide the opportunity to post the images to social networking sites with just a few clicks. The main point is that you don’t just create a standalone email with some information, but instead create the beginning of an online experience for the visitor that can result in a new membership, a buzz among friends from the photo that just appeared on Facebook, and an introduction to the web site of a venue that may hold more than what the visitor expected.