The issue of child safety has always been a subject of concern and concern. A series of products derived from it are also emerging in an endless stream, among which the relatively high shooting rate is such positioning watches. The most obvious representative of the bombing of advertisements here is Mori's “Little Genius†series. At the beginning, I didn't really care about this kind of product and thought it was very rough. Now I think so too. However, as children grow bigger and larger, their joy of free play increases, and their energy is limited. To ensure that free children are controlled to a certain extent, such products enter the line of sight. In the previous period, I had done some homework. Little geniuses, LeTV, 360, Huawei, Xiaomi, etc. have all studied meticulously. Feeling similar to the function, so casually into the 360 ​​mid-section models, all the way to use one, basic functions to meet the needs. However, this type of watch has always been a 2G network, and it's just that Aunt pushes LeTV to watch this 4G watch. The heart, action, and aunt touch me. So there was this test report.
Love in the palm of your hand - Let's watch KIDO's 4G smart children's watches
After receiving the aunt's public test success message, they couldn't support the circle of friends and dazzled them. It was also considered as a circle for the aunt. It was conservatively estimated that more than 10 people entered the aunt's "claw."
Next is a long wait for delivery, I wonder if it is not the age of the aunt, this action was delayed for a long time, I only received a delivery notice for a long time, arrived at the time of the family travel, in order to complete the public test on time, but The buddy who was at home helped sign and settled the time to forward to the next city where I was on vacation. At the moment I am completing this evaluation in Xingcheng, Liaoning. It is also worthy of the trust of Aunt! I hope that the mother will be fortunate in the future.
The Aunt’s packaging was relatively simple. The plastic bubble was wrapped with eye-catching and enviable value. What did the advertisement say? "Minimal but not simplify".
Hardware aspect
After dismantling, unlike the round packaging of most children's watches bought before, LeTV's rectangular packaging used this time, at first glance, I thought it was toothpaste, and the size is similar!
Music as the packaging is not complicated, unlike the 360 ​​plastic packaging full carton structure, relatively simple, do pull type. The overall style is unified.
The previous participation in the evaluation are guessing whether this is an engineering prototype. This time, the manufacturer has directly indicated that the engineering machine is also considered to be the scene of the public survey. However, from the appearance and actual use, although it is marked as a working machine, nothing is wrong. Properly. All kinds of functions and data are complete. Like a mature new product. 
After unraveling the structure chart, a quiet beauty man, only to see why he wants to design the growth of the structure! ! The upper layer is a plastic abrasive device embedded in the watch body. Below are 2 cartons for storage of various accessories.
The last accessories family portrait, more conventional, watch body, safety instructions card, manual, data line (without charging head), there is a more special is the use of robot instructions card, should be considered more personalized things, feel all The accessories work well and are in line with the positioning.
Good selection of watch materials, matt surface shell structure, blue and white, texture and difficult to leave fingerprints, strap material selection is quite good, obviously better than 360. Anyway, to bring children should be able to look assured!
The right side of the table is a common layout for such watches. There are 2 buttons. The above is the POWER button. Press and hold to turn on or off. Press to return to the dial. The middle hole is the microphone. The following is the SOS button. Press and hold to dial the parent. Phone, click to return to the previous menu, and when you receive a call, you can mute it by pressing once again. At the same time, these two keys are also the temporary volume keys when making calls and chatting.
On the left side of the table is a standard Android phone charging hole, 5v 0.45A standard input. Here is a big praise, the last watch is charging a non-standard interface, directly down the child with his parents to forget to bring the charger after spending 20 yuan a postal mail can not feel 10 yuan charger. The honeycomb hole is a speaker.
The upper side of the watch is a Nano SIM card slot. Here is another big praise. Don't underestimate the external design of this slot. The previous table is not like this. It is very inconvenient to remove four screws to install it. Because I was in the field when I replaced this watch card, I didn't have a screwdriver. It really bothered me for a long time, and I spent a lot of effort to find an optical shop to ask for a replacement.
On the back of the watch, all kinds of communication information are complete. The S/N IMEI MEID CMIIT ID code is complete, and the model is also labeled as TD-LTE wireless data terminal Kido K2, indicating that this is a small mobile phone.
Shanghai Arts Network Technology Co., Ltd. produced. 
Appearance hardware summary: Yan value, good workmanship, without any software intervention, the feeling of ergonomic design is reasonable, basic functions to achieve and get started easy and simple, standard port charger, external SIM card slot, and quick disassembly of the ear design Give a good use experience.
Software use
First of all, it is definitely to download the APP, Android can directly scan the code to download, OS will be downloaded through the APP STORE, there is no difficulty for those who have had such a watch. The downloaded software name to be noted here is correct. This is the picture below! Because when you search for APPs, you will come out with lots of software related to KIDO.
The post-installation interface mainly implements the following functions. Among them, positioning, step counting, and two-way conversation are more common, and the function of small red flowers is relatively novel. It is to assign a task to the child on the mobile phone, give a hint on the watch, and give it a corresponding small red flower. Seems to be simple but gives the child good encouragement! Bear children's world you do not understand
Positioning is to rely on GPS network base station positioning, there is a power-saving mode in the watch, is based on several types of positioning switch, GPS is the most expensive, but the highest accuracy, the network base station positioning second, but the function of the WIFI positioning me It is not understood. Because the watch has no WIFI function at all!
Sports pedometer is similar to the bracelet function, but he made a big data that should be the corresponding watch in the country, you can do analogy! Increase child sports power!
When the watch is used, it must be registered first. It is relatively simple. After entering the administrator's mobile phone, complete the registration. Any new person 
Enter your mobile number for your child at this time and complete the registration.
All of these watches are the same and must be bound to see further below. This means that you can't download a piece of software without buying a watch yourself. All manufacturers are the same.
The following is the binding watch, known as the eye color screen, the actual use down feeling pretty good, although there is no clear retina does not make people feel uncomfortable. The ink recognition interface is a watch. There are two kinds of dials, one is a pure digital dial, the other is a real analog dial, and the upper left corner is a signal display, which clearly shows whether the current network is 2G or 4G.
A total of seven main interfaces and sub-interfaces can be displayed:
1, set
Volume adjustment
Dimming
2. My activities
Healthy step
Safflower mission
Event reminder
3, KIDO robot
4, dial
5, my family
Family chat
family
6, my friend
7, add friends
Family group chat is a relatively common project, which is the intercom, the interface is similar to the WeChat, the use is relatively simple, easy to use. Don't go into too much detail.
KIDO robot is a small K feature that can ask English, predict weather, count, listen to children's songs, encyclopedias, listen to stories, and learn ancient texts. However, practical use does not feel practical. First of all, he is dependent on the network. If the network is poor, then it is impossible to use it under 2G network. Small K can only listen to it. No reaction. And because this is taking the flow, the use of the bread is far greater than practical.
The main interface of the software can directly and clearly see the children's positioning. The basic functions can be realized. Telephones and language chat can be directly completed. It can be said that basic functions are implemented well, and people meet the most basic use requirements.
The history track playback also fully embodies the advantages of the 4G network. It is dense and accurate, and the 2G watch's drift is significantly reduced.
The watch setting is also relatively simple. These basic functions of the watch of the same kind are all there. If you see it, you will know how to set it up. There is a timer switch function that feels good, avoids wasted electricity and ensures that the impact of the watch on children is minimized in the evening. Power saving mode
The language chat interface is similar to WeChat. It is easy to use and can choose group chat or chat alone.
The corresponding functions on the watch can also be implemented on the mobile phone one by one.
to sum up:
When I applied for the evaluation, I said that these products must be considered from the perspectives of ease of use, radiation, battery life, and humanization of the software. After using it for a round, I feel that K can meet the above points. It is a qualified product and can meet the actual needs of users who purchase such products.
1. Appearance design is quite satisfactory, eye protection color screen, material and materials work in line with the positioning and pricing, battery usage is not conventionally seen too short or too long;
2, humanized hardware design is reasonable, standard charging port and external SIM card design is commendable;
3, support 4G network, positioning speed and striking frequency is significantly stronger than other brands of watches;
4, the software design of the mobile phone is more reasonable, the use of basic functions, to achieve a clear
5, the design of the watch is slightly complicated, the interface is more, if the child is slightly smaller, it is difficult to use.
6, there is no answer to the robot's small K some untrue.
Written after the evaluation.
Actually speaking, I am not optimistic about the prospects of such products. The reason is very simple. The threshold is too low, and the functions are easier to implement. In fact, someone with a little knowledge of software can understand that these functions can be implemented on the phone with software functions. , And certainly more powerful, there is no need to make a single product. If we want to make a single product, I think that propaganda can be done without positioning the child to locate the watch and expand it for the elderly. The positioning of disabled people and even pets can be used. The function is to use orientation and life as the main direction. Others The function is second only. Although positioning and endurance are mutually constraining conditions, I personally tend to be quick and accurate because it is actually used. Well, not arrogant, custom, home Meng Meng September town building! 
Lead Free Piezoelectric Elements
The Co-Al Co-doped Barium Titanate
Lead-free Piezoelectric Ceramics was successfully developed by Yuhai company
through repeated experiments. By Researching the influence of Co-Al Co-doping
on the structure and properties of Barium Titanate-based piezoelectric
ceramics, the formulation and preparation technology of Barium Titanate-based
piezoelectric ceramics were optimized. Yuhai`s BaTiO3 was prepared by conventional
solid-phase sintering method, with the piezoelectric constant d33 (>170pC/N),
dielectric loss tgδ≤0.5% and mechanical coupling coefficient Kp≥0.34.
Barium titanate lead-free piezoelectric
ceramics are important basic materials for the development of modern science
and technology, which was widely used in the manufacture of ultrasonic
transducers, underwater acoustic transducers, electroacoustic transducers,
ceramic filters, ceramic transformers, ceramic frequency discriminators, high
voltage generators, infrared detectors, surface acoustic wave devices,
electro-optic devices, ignition and detonation devices, and piezoelectric
gyroscope and so on.
Application: military, ocean, fishery, scientific research,
mine detection, daily life and other fields.
China Patent of Yuhai company`s BaTiO3
Chinese Patent No.: ZL 2011 1
0126758.6
Name: Lead-free Barium Titanate
Piezoelectric Material with Addition of Cobalt and Aluminum
Lead free piezo material BaTiO3
Lead-free Material
Properties
BaTiO3
Dielectric Constant
ɛTr3
1260
Coupling factor
KP
0.34
K31
0.196
K33
0.43
Kt
0.32
Piezoelectric coefficient
d31
10-12m/v
-60
d33
10-12m/v
160
g31
10-3vm/n
-5.4
g33
10-3vm/n
14.3
Frequency coefficients
Np
3180
N1
2280
N3
Nt
2675
Elastic compliance coefficient
Se11
10-12m2/n
8.4
Machanical quality factor
Qm
1200
Dielectric loss factor
Tg δ
%
0.5
Density
Ï
g/cm3
5.6
Curie Temperature
Tc
°C
115
Young's modulus
YE11
<109N/m3
119
Poison Ratio
0.33
Piezo Element,Piezo Ceramic Elements,Piezoelectric Ceramic,Pzt Tubes
Zibo Yuhai Electronic Ceramic Co., Ltd. , https://www.yhpiezo.com