Before you choose
As discussed earlier, to select the right immersive educational solution, you need to be aware of some technological aspects. First, you should have a close look at the hardware. Simulations differ in the system that tracks human motions, then digitalizes them and transfers signals to the screen or the oculars. These differences are very important when you try to find the best solution for your school.
2D or 3D?
There are tools that use flat screen solutions, other tools give you a 3D experience. Advantage of 2D solutions is that they are easy to use for older generations. Flatscreens are easy to employ in professional orientation test for people who never tried virtual reality tools. In approaches that put weight on gradual improvement, flatscreen is the first step where students are taught the basics. They are only allowed to move on to 3D reality when they passed 2D exams.
Sensors
What type of sensors the device works with? Magnetic? Ultrasound? Optical? Can the signal be disturbed by environmental changes? The curtain in the classroom moves and the light changes in a sunny afternoon and you have to recalibrate. Are there other machines using ultrasound nearby? If yes, one of the machines may end up in the cellar.
Ultrasound
Pros: Great advantage of ultrasound sensors that they cannot be disturbed metal objects nearby. They are not disturbed by any type of light. There are some seldom cases where other ultrasonic devices, such as anti burglar alarm may affect them. Simulators equipped with US sensors do not require physically modelled workpieces, so a new shape is relatively easy and cheap to import from a 3D model file. Other advantage is you do not have to recalibrate or maintenance. Another big advantage is US sensors are extremely precise. In motion tracking systems their sensitivity is around 1/00 millimeter.
Cons: they are expensive. They are fragile and the cost of repair is high. Other disadvantage is the technology is protected by expensive patents, so it is not a widespread technology.
Magnetic Resonance
Pros: High precision of 1/10 of a millimeter in motion tracking. Simulators equipped with Magnetic motion tracking system do not require physically modelled workpieces, so a new digital shape is relatively easy and cheap to import from a 3D model file. Other advantage is the sensor is relatively cheap compared to ultrasonic sensors.
Cons: Magnetic sensors are sensitive to a bigger pieces of iron or steel nearby. Real metal tools need to be substituted with plastic replicas with similar weight of the originals.
Optical sensors
Pros: Very cheap. As of september 2022 one camera in an optical motion tracking system is around 100 euros. Magnetic sensor is around 1000 euros. Optical motion tracking is cannot be disturbed by metals.
Cons: Accuracy is limited to 0,5 cm. Headsets equipped with cameras and electronics are heavy. Physically modelled workpieces are required. Matrices with identifier symbols can fade out after a while. Integrating new physical workpieces are special designs so they are expensive to produce.
Moving parts
There are producers who integrate moving physical parts in the simulators. Pros: moving parts can shorten the learning curve at the beginning.
Cons: After a certain lifetime the product will need spare parts or fixing. If the producer is overseas the repair will take a long time. Real parts may prevent very fine psychomotor motions. Using only virtual parts makes learning harder but leads to learn a very precise motion.
In a training center Eger, Hungary Virtual Welding simulators that use no moving parts, are introduced in sewing class curriculum, because of their extremely high accuracy in psychomotor skills improvement. Source: (Learn Virtual Europe)
Here is a specific example from welding. An important difference of "cheap" optical motion transmission system: it cannot realize and display the weight loss of the electrode during welding. It only senses that the end of the device is in front of the workpiece, but it cannot simulate the weight loss of the welding material in real time, thus teaching poor movement coordination.…
Lifespan
What is the reliability and lifespan of the motion tracking system? Needs to recalibrate soon? Goes wrong after a hundred students? Read reviews, ask other customers, negotiate with the producer to guarantee a good service level. Try to be as specific as you can when negotiating service levels such as availability of service, deadlines. The motion tracking system is the soul of the hardware. It might be cheap at the time of buying but may cost lot more afterwards.
Integrability
Now, see the software. Is the simulation automatized enough? In other words, does simulation allow you to learn without a constant engagement of a teacher? The main goal is not only to provide "realistic" visualization, but give a pedagogical structure. Through it, the device itself can teach the correct coordination of movements for the practical application of the skill as quickly and accurately as possible. Some producers sell yet unexplored solutions, which have serious shortcomings and limitations. One sign of the inexperience is that its use still requires a permanent teacher supervision, which means the complete engagement of the practical instructor while using the simulation. Thus, in case of welding for example, the real savings are reduced to only the materials and gases to be used in the training, and the wage cost savings achieved by offloading the instructor cannot be counted.
Without a good pedagogical system, the simulator is useless in vocational training, because just as in the traditional training, the student, if left alone, can develop "bad habits" that are difficult to correct afterwards.
Some manufacturers do not have a record of how the simulation can be integrated into practical training in either school system or adult training and the extent to which savings can be realized. Thus, the return period of the product cannot be calculated or estimated.
Mobility
You may consider the transportability. Almost each producers offer easy to transport simulators with limited capabilities. There is a trade-off between portabilty and capabilities. If you want a full immersive tower crane with haptic seat, you have to sacrifice easy transport.
Customized to person?
Can the simulation improve concentration skills directly and individually? Concentration means control of attention. It is the ability to focus the mind on one subject, object, or thought, and at the same time exclude from the mind every other unrelated thought, ideas, feelings, and sensations. Is the software suitable for measuring users' concentration ability and improving their individualized ability? This is an important aspect of a skilled worker that he can constantly concentrate on what he does. And the development of this ability is very much needed even in school. Ask the manufacturer to show you specifically how the device and its software measure focusing skills. Does it provide systematic training with sessions? Does it show improvement with numbers? Can the software give personal profiles for individuals in concentration skills development?
Knowing the clients
This aspect is the human factor. An important selection criterion is also the depth to which the distributor of the product knows the needs of the schools. They supposed to have experience in training. They should have new ideas to support the school in integrating the simulation into practical training, based on their practical experience. The real experts are in daily contact with skill trainers, so they can provide right instructions and information about the effective ways of integrating simulation, even online.
It is therefore worth examining the existence and clear applicability of the software that performs important analyses for the instructor from the point of view of the management of the training, because any differences will slow down the problem-free synchronization in the virtual environment with the virtual and real practical training.
Pricing Plans
Keep in mind that there are two main strategies in the market. One is you can get the product for cheap and you pay a lot not soon afterwards. The other one is you investment is higher when you purchase the product but all the services afterwards are cheap. Even the trainings and upgrades can go for free for the lifetime of the product. These strategies have different philosophies: the former is much like a bank loan assuming you will have no money now but you will have some later on, the latter resembles a grant on investment assuming you will need a kickstart and you can get enough budget for it now. Think and plan carefully with your cashflow before choosing.