A workplace at the POS should meet multiple requirements. The customers are the centre of attention. They want to be served in a quick, reliable and friendly way. The quality of a POS workplace becomes obvious when the shop is crowded with customers so that there is a great crush at the checkouts. The cashiers have to solve various problems under time pressure: goods with incorrect prices, products missing on the shelves, special offers are not yet or no longer available, customers do not have enough money with them, people complain about defective products etc. Many of these problems originate from the organisation but have to be resolved at the end of the process chain, that is, at the checkout. These tasks can be dealt with more easily if the POS workplace is designed in a bright and clearly organised manner, providing suffi cient space for customers, staff and products, under pleasant ambient conditions (no draught), at a reduced noise level which is normally quite high in supermarkets.
Good ergonomics at the workplace pay off in multiple ways: the physical and psychological health of the staff is protected. You can hardly serve customers in a friendly and superior manner when your back aches due to a chair with insuffi cient vertical adjustment, or when your arm muscles are fatigued because the products on the conveyor do not get close enough to the scanner, or when you suffer from running of the eyes because the monitor is placed too far away. And once you lose your friendliness, new stress factors will result, for example from the behaviour of annoyed customers and consequently superiors. This is the beginning of a downgrade where one stress factor increases the next one. At the end ofthe day this may affect the economic success of a store because customers go to another shop where they are served in a more friendly way or even visit the competitors’ shops more Frequently.
With the touch type of POS terminal the input and output of information are integrated on a single touch-sensitive screen. There are advantages to this technology, but the userfriendliness or usability of the POS system may be adversely affected (eyes and hands may get “mixed up“). The input is mainly realised via the scanner in a more or less automatic way, whereby the screen is reserved for mere output, that is, product prices and designations. Special operations, however, require input on the touchscreen, for example in case of void, special prices, particular payment modes, etc. What matters now is that the operator’s fingers or hand do not hide important displays or erroneously touch or release the wrong buttons, that the virtual keys and buttons are big enough so that exhausting “exercises of dexterity“ are avoided, that the visual feedback from the system is quickly and reliably distinguished, and many more.
The layers of the ergonomic design of a touch terminal can be visualised by an onion with its various skins from the outside to the inside. The outer “skin“ represents the positioning of the touchscreen. Can it be adjusted in height, distance and inclination by the operators themselves? As a rule, various employees alternately work at a terminal, the lighting conditions may vary during the day, and an adjustment of the screen position may also be necessary due to fatigue symptoms on the part of the staff. The next “skin of the onion“ represents the brightness and contrast settings of the screen. Currently many people, without being aware of it, work at screens on which brightness and contrast are set too high, causing fatigue at an earlier time. The screen should therefore allow to adjust these settings.
The staff should be trained to learn which settings are ergonomically right. They should be able to set the right size of numbers, characters and buttons on the screen. This is important because the distance between the screen and the eyes varies during work, and the biggest distance is decisive for the settings of the character size. In addition, people are vain and often try to work without glasses. Though the employer is not obliged to take human vanity into consideration, the glasses of the employees concerned are frequently not made for the change between the near-vision area (reading) and the extended working area. Finally we get to the inner “skins of the onion”. These represent the “logic“ of the functions – from the staff’s point of view though, not as the software developers see it. Here is a great potential for the improvement of usability, for example regarding article search or database functions, or the accounting of vouchers.
As far as the user-friendly design of the touch terminal is concerned, individual elements may tone down or intensify each other. A complicated process becomes easier to handle when the corresponding button is a bit bigger and better marked. An optimised and more reasonable functional sequence requires less concentration which may then be dedicated to the customer and may reduce the overall stress.
Target groups are changing as well. Besides the experienced “cashier“ who is able to operate the POS terminal with uncanny sureness, many young people, trainees and part-time jobbers are nowadays working in supermarkets. These people do not have any experience with the POS software which was developed over many years. They are at home in the web at amazon, eBay, Facebook, Google and Wikipedia, they are fit in using their PCs and smart phones. The “logic“ of the functions at the POS workplace is not revealed to this group of staff right away, and more often than not it is contradictory to the applications they are familiar with from the web.
As regards future developments of touchscreen systems, we can distinguish between short-term, medium-term and longterm development potentials: the short-termperspective is that also touchscreen systems will benefi t from the general development in computer technology, that is, they will become more powerful and cheaper and thus create the prerequisites for improved screens and quicker software. Under ergonomic aspects, however, the user interface and the functional procedures will still need to be re-designed in order to achieve a noticeable benefit from the point of view of the employees. The current technology still provides a great potential for short-term improvements.
I cannot predict when the multi-touch technologies known from iPhone, iPad and related systems will also be found at POS workplaces. The technology is available, and its integration will become ever cheaper and simpler. The introduction of such systems, however, depends on other factors as well and is subject to the decisions of the suppliers and users of POS technology.
In my view, multi-touch systems will rather be a medium-term solution at the point of sale. As consumers, we are enthusiastic about these devices, it is fun to work and play with them. iPhones or iPads are operated with both hands, one hand holds the device while the other operates the multi-touch display by means of gestures. At the POS workplace, however, the screen is fi xed. One hand normally holds the product to read the bar code, while entries are made using the fi ngers of the other hand. We will have to examine what the advantages of operation by gestures are compared to the current forms of Interaction.
On a medium-term basis screens can be improved signifi cantly. For example, so-called “electronic paper” (E-Paper) is used for the displays of E-Books like the Kindle offered by amazon or the Oyo supplied by Thalia. These displays represent the information by means of black and white (in future also coloured) droplets and do not require any background lighting. The brightness and contrast values are much better than with conventional LC displays and come close to the quality we know from printed media like newspapers and books.
This technology could thus help to significantly reduce the strain resulting from work at the screen, and by the way, also the energy costs. E-Paper requires just a small fraction of the energy consumed by LC displays.
In the long run though, this may happen earlier than I am able to imagine today - the POS workplace could have a totally different appearance. Already now we can see the required technologies in other products: Microsoft’s play station xbox demonstrates interaction by means of gestures and movements. The player does not even have to touch the screen any more; movements are recorded in a three-dimensional way and translated into commands to the program. Applications of “augmented reality“ are known from the iPhone and other smart phones. With the sensors built in the device the mobile phone “knows” where it is located and the picture of a building, for example, is taken by means of the camera. Powerful computers in the web “recognise” which building it is and a corresponding information is displayed in the real picture taken by the camera.
Using this and other technologies the POS workplace of the future might consist of an apparently “simple” table with built in sensors to record the products, and other sensors to select the buttons which are projected on the table to control the software. So the table becomes the keyboard, the monitor and the touchscreen at the same time. From above, a projector projects the necessary displays onto the table. The technical equipment becomes invisible, no bulky devices separate the staff from the customer. We can imagine this scenario to be a traditional checkout with the conventional division of labour between the customer and the cashier, or a self-service terminal, or a mix of both types.