Domestic Robots

Jan Karlsson, UNECE

As domestic cleaning takes place in private households, there is a huge market potential in terms of units for new and replacement articles. Due to the relative low degree of utilization, the price has to be far lower than for commercial cleaning robots. This is achieved through simplifications such as the random walk system. In combination with a sensor, detecting already worked areas, it is regarded to be as efficient as pre-planned path systems. It can evade obstacles and continue its work right away. In areas with many obstacles such as furnished rooms or gardens with many plants this should be especially advantageous.

Vacuum cleaning robots can be used not only for private homes but also for offices, doctors’ surgeries, etc.

The idea behind robotic domestic devices is to liberate people from unpleasant daily chores and give them more free time. The robots are simply set in their working area, where they operate by themselves. Manual interference is thus only needed to change the overall operating area, e.g. the room.

Vacuum cleaning robots are small enough to pass under furniture and their round shape allows them to easily manoeuvre themselves out of traps. They are equipped with optical sensors to detect the degree of soiling, so that the robots can distinguish previously cleaned areas and pass on to those left out. The robots automatically return to the charging station when their batteries are low. The dust bag is emptied during the reloading process. Infrared sensors protect them from falling down steps. The vacuum cleaning robots are slower than a normal vacuum cleaner but they do nothing else but clean all day long. They are also more accurate in cleaning the area and the power consumption is lower than that of conventional vacuum cleaners.

Lawn-mowing robots are the modern replacement for sheep. They stay in the garden over the summer and ensure a neatly cut lawn. Grass cuttings from the mowing robots do not have to be removed either. Regular cutting keeps the lawn so short that they can be left to act as fertiliser. The price, depending on the model, is about CHF 3,200.

Up to the end of 2000, very few vacuum cleaning robots were sold. The first vacuum cleaning robot was to have been commercially launched in November 2000. It has now been delayed until the first half of 2002.

The forecast for the overall market of vacuum cleaning robots, lawn-mowing robots and other household robots for the period 2001-2004 is 425,000 units.

Taking a longer-term perspective, say 10-15 years from now, domestic robots can very well have started a diffusion process similar to that which the PC, the mobile telephone or the Internet have had in recent years. In fact, the wide usage of the latter type of equipment greatly facilitates the introduction of service robots. In the next few years almost all homes in Western Europe will have mobile phones, PCs, and Internet connections. This is particularly true now after the decisions of the European Commission of realizing the so-called “e-Europe”. The well-established “digital knowledge,” or at least familiarity with it, in particular among young and middle-aged persons, will facilitate the acceptance of robots working in our homes.

Increasingly various types of tools and equipment in our homes (heating systems, fire and burglary alarms, stoves, ovens, refrigerators etc.) will incorporate microcomputers and, above all, will be able to communicate with each other, either by cable, electric wiring or by infrared or other wireless modes of communication. We will be able to control them from remote places, using our mobile phones as terminals. In this environment, domestic robots will serve as an important link between the various types of computer-controlled equipment and systems in our “wired” homes.

With the above described complementary technology in place and with improved performance of domestic robots at a lower price (i.e. following a similar curve of price/performance ratio as other electronic goods), there is a potentially huge market within reach. Modular designed robot platforms to which various types of utilities, e.g. for vacuum and other types of cleaning, can be attached as well as articulated robot arms, various types of sensors and vision systems could carry out a variety of tasks in our homes. They could vacuum clean, scrub the floors, empty the dishwasher and place the china in the cupboards, lay the table, take out the garbage, open doors, guard the house against intruders and fire, mow the lawn, increase the mobility and security of old and disabled persons and much more. Increasing functional flexibility will allow one robot system to free us from a number of routine jobs.

How much do we value our leisure time? It is reasonable to assume that it is a function of our hourly income and of the amount of leisure time we have left after having carried out our professional work and the necessary household tasks. If the time saved through using domestic robots is used for paid work, then it is rather easy to relate a value to the freed time and from that attach an income to the domestic robots. For high-income people there will thus be strong incentives to use domestic robots.

While our real incomes are following an increasing trend, the price of domestic robots rather tends to fall which results in falling relative prices. Economies of scale will make the price decrease considerably and will allow the domestic robots to be widely diffused. All this supports the scenario that by 2015, domestic robots might be as common in our homes as the PC is today.

While manual domestic appliances, whether it is vacuum cleaners or lawn mowers, are very noisy and require a guiding person to walk them up and down, robots operate quietly and autonomously. In the case of solar mowers, they have a solar panel to create their own energy: the internal computer decides whether to send the energy straight to the motor or to the batteries. A low current loop, which is placed under the earth, limits their working area and keeps them in place. The robots also have an acoustic alarm to prevent their theft.

The silent electronic motors allow for round-the-clock operation without disturbing anybody nearby. Operating in that way, the robotic mowers can cover up to 1,200m2 of lawn.2 In contrast to the extremely polluting gasoline driven traditional mowers, the electronic ones have no emission. The operation costs, in particular for the solar powered mowers, are lower than for gasoline driven ones and they require less maintenance.

The robots are not as strong or fast as manual devices, therefore they have to be in daily round-the-clock operation to have the same result. Due to their relatively low degree of utilization, and the availability of equally effective manual devices, domestic robots stand in direct comparison. The difference in purchase price must not exceed the value accorded to personal free time. As today domestic robots are still significantly higher priced than manual devices, they are mainly marketed among high-income people, who assign a higher price to their alternative use of time gained by the robots and can afford it. This of course acts as a curb on mass consumption.