Intelligent robot design for home healthcare

1 Introduction
　　 The digital home is the basic unit of the future smart community system. The so-called "digital home" is based on the internal home network to provide intelligent services covering the entire home, including data communications, home entertainment and information appliance control functions.

　　One of the main contents of digital home design is the realization of communication functions, including communication between the home and the outside world and communication between related facilities within the home. Judging from the current development, external communications are mainly accessed through broadband. Internet, and for communication within the home, the author uses the currently more competitive Bluetooth (Bluetoothlh) wireless access technology.

　　Traditional digital homes use PCs for overall control, which lacks humanization. Based on the idea of ​​artificial emotion, the author designs an intelligent robot equipped with a variety of external sensors. This intelligent robot is regarded as a family member and can control the digital home through it.

　　This article mainly designs models for the application of intelligent robots in digital home healthcare. Bluetooth technology is used to communicate between intelligent robots, medical instruments and control PCs. The cost of the entire system is low, the functions are relatively comprehensive, the extended application is very broad, and it has great market potential.

2 Overall design of intelligent robot
2.1 Multi-sensor system of intelligent robot
　　The most important related field in robot intelligent technology is the robot’s multi-sensory system and the integration and fusion of multi-sensory information [1], collectively referred to as the hardware and fusion of intelligent systems. software part. The fusion and use of external sensors such as vision, hearing, force, and touch and the internal sensor information of each joint of the robot can enable the robot to complete important functions such as real-time image transmission, speech recognition, scene identification, positioning, automatic obstacle avoidance, and target detection; to The robot plus related medical modules (CCD, CAMERA, stereo microphone, image capture card, etc.) and special medical sensor components, coupled with the medical expert system, can realize medical care and remote medical monitoring functions. The multi-sensor system block diagram of the intelligent robot is shown in Figure 1.

2.2 Intelligent robot control system
　　The robot control system consists of 2 parts: First, the host computer, generally using a PC, which completes tasks such as robot motion trajectory planning, sensor information fusion control algorithm, visual processing, human-machine interface and remote processing; second It is a lower computer, which generally uses a multi-chip microcomputer system or DSP as the core component of the controller to complete functions such as motor servo control, feedback processing, image processing, speech recognition, and communication interfaces.

　　If a multi-microcontroller system is used as the slave computer, each processor completes a single task and completes the overall system function through information exchange and mutual coordination, but it is obviously lacking in signal processing capabilities. Since DSP is good at signal processing, and intelligent robots often require signal processing, image processing and speech recognition, DSP is used as the controller of the intelligent robot control system [2].

　　The control system uses DSP (TMS320C54x) as the core component and consists of Bluetooth wireless communication, GSM wireless communication (supporting GPRS), motor drive, digital compass, sensory function sensors (vision and hearing, etc.), medical sensors and multiple-select serial port communication (Rs -232) module and other components, the control system block diagram is shown in Figure 2.

　　(1) The system controls the movement of the robot through the drive motor and the steering motor. The steering motor uses the information from the digital compass as a feedback quantity for PID control.

　　(2) Use Ericsson's ROKl01007 circuit as a Bluetooth wireless communication module to realize communication between the intelligent robot and the host computer PC and other medical and health care instruments based on Bluetooth modules.

　　(3) The GSM wireless communication module that supports GPRS supports data, voice, short message and fax services, and uses mobile phone communication to communicate with the remote medical monitoring center.

　　(4) Since TMS320C54x has only one serial port, and sensory function sensor modules such as Bluetooth module, GSM wireless module, digital compass, and visual and auditory sensors all use RS-232 asynchronous serial communication, so a multiple-select-one serial port must be designed. The communication module performs conversion processing. When TMS320C54x needs data from the Bluetooth wireless communication module, it is gated through the circuit; when T~MS320C54x needs data from a sensor module, it turns off the gate of the previous wireless communication module and gates the sensor module at the same time. In this way, each module completes the serial communication with 1~MS320C54x.

3 Realization of main medical care functions
　　Intelligent robots can provide the following services for digital home medical care:
　　(1) Medical monitoring monitors
　　the main physiological parameters of family members such as ECG, blood pressure, body temperature, and respiration through medical sensors integrated with Bluetooth modules. and blood oxygen saturation, etc. are detected in real time, and local results are provided through the robot's processing system.

　　(2) Remote diagnosis and consultation
　　use the robot's visual, auditory and other sensory functions to transmit the collected video, audio and other data combined with various physiological parameter data to the remote medical center, which will be remotely monitored by experts from the medical center and combined with the medical expert system Consultation on the health status of family members, that is, providing services such as viewing (video), smelling, asking (audio), and examining (various physiological parameters) [3].

3.1 Robot vision and video signal transmission
　　The video signal collected by the robot has two functions: providing robot vision; and transmitting the collected static images and dynamic pictures of family members to the telemedicine center.

　　The role of robot vision is to obtain the required information from 3-dimensional environmental images and construct a clear and meaningful description of environmental objects. Vision includes 3 processes:

　　(1) Image acquisition. The 3D environmental image is converted into electrical signals through a visual sensor (CCD CAMERA for stereoscopic imaging).
　　(2)Image processing. Image-to-image transformation, such as feature extraction.
　　(3) Image understanding. An environment description is given based on the processing.

　　Through the transmission of video signals, doctors in telemedicine centers can understand the physical and mental status of family members in real time. Intelligent robots capture images suitable for healthcare and diagnostic needs based on the doctor's needs, selectively transmitting high- and low-resolution images. In the process of medical care, there are two different requirements for image transmission:

　　(1) When doctors observe the color of skin, lips, tongue, nails and facial expressions of family members, they need to transmit static high-definition color images; The method adopted is to transmit a high-definition still image at intervals of a period of time (for example, 5 minutes).

　　(2) When doctors use dynamic images to check the body movement ability of family members, they can transmit images with lower resolution and smaller size. The method used is to perform reasonable compression and recovery to ensure real-time performance.

3.2 Robot hearing and audio signal transmission
　　 The audio signals collected by the robot also have two functions: one is to provide the robot with hearing; the other is that with the help of audio signals, family members can communicate with doctors, and doctors can understand the health status and health status of family members. mentality. The transmission of audio signals provides a way for doctors to communicate verbally when providing medical care to family members.

　　Robot hearing is speech recognition technology. Healthcare intelligent robots are equipped with various acoustic interaction systems. They can conduct medical testing and monitoring according to the orders of family members. They can also do housework, control digital home appliances and take care of patients according to the orders of family members.

　　Sound is acquired using multiple stereo microphones. Since the frequency range of sound is approximately 300Hz-3400Hz, sounds with too high or too low frequencies do not need to be transmitted under normal circumstances. Therefore, doctors and family members can perform normal operations by only transmitting sounds with a frequency range of 1000Hz-3000Hz. communication, thereby reducing the bandwidth occupied by transmitting audio signals, and then using a suitable communication audio compression protocol to meet the requirements of real-time audio. The auditory system of the intelligent robot is shown in Figure 3.

3.3 Collection and transmission of various physiological information
　　Traditional detection equipment is connected to the human body through wired methods to collect physiological information. Various connections can easily make patients nervous, resulting in inaccurate detected data. The use of Bluetooth technology can solve this problem well. Medical micro-sensors with Bluetooth modules are placed on family members to try not to interfere with the normal activities of the human body. The collected data are then transmitted to the receiving device through Bluetooth technology and processed. for processing.

　　A detector with a Bluetooth module is installed on the smart robot as a receiving device. Various medical sensors transmit the collected physiological information data to the detector through the Bluetooth module. The detector has two working modes: one is to transfer the data It is processed by the intelligent robot and provides local results; the second is to connect to the Internet (it can also be sent back directly through the GSM wireless module), and the data is transmitted to the remote medical center through the network to achieve the purpose of medical care and remote monitoring. Video and audio data are also transmitted this way. The data transmission system of the intelligent robot is shown in Figure 4.

4 Application of Bluetooth module
4.1 Overview of Bluetooth technology
　　 Bluetooth technology [4] is a short-distance wireless communication technology used to replace cables or connections. Its carrier uses the globally public 2.4GHz (actual radio frequency channel is f=2402+k×1MHz, k=0, 1, 2, ..., 78) ISM frequency band, and adopts frequency hopping method to expand the frequency band, frequency hopping rate is 1600 hops/s. 79 channels of 1MHz bandwidth are available. Bluetooth devices use GFSK modulation technology, the communication rate is 1Mbit/s, the actual effective rate can be up to 721Kbit/s, the communication distance is 10m, and the transmission power is 1mW; when the transmission power is 100mW, the communication distance can reach 100m, which can meet the needs of digitalization family needs.
4.2 Bluetooth module
　　ROKl01007 Bluetooth module [5] is a wireless baseband module suitable for short-distance communication launched by Ericsson. It has high integration, low power consumption (RF power is 1mW), supports all Bluetooth protocols, and can be embedded in any device that requires Bluetooth functionality. This module includes five functional modules: baseband controller, wireless transceiver, flash memory, power management module and clock, and can provide functions up to the HCI (Host Control Interface) layer. The structure of a single Bluetooth module is shown in Figure 5.

4.3 Master and slave device hardware composition
　　Bluetooth technology supports point-to-point PPP (Point-t0-Point Pro-tocol) and point-to-multipoint communication, and wirelessly connects several Bluetooth devices into a piconet [6] . Each piconet consists of a master device (Master) and several slave devices (Slave), with a maximum of 7 slave devices. The master device is responsible for the actions of the communication protocol. The MAC address is represented by 3 bits, that is, 8 devices can be addressed in 1 piconet (the number of interconnected devices is actually unlimited, but only 8 can be activated at the same time. , of which 1 is the master and 7 are slaves). The slave device is controlled by the master device. All equipment units use the same frequency hopping sequence.
　　The miniature medical sensor with Bluetooth module is used as the slave device, and the detector with Bluetooth module on the smart robot is used as the master device. The hardware of the master-slave device mainly includes antenna unit, power amplifier module, Bluetooth module, embedded microprocessor system, interface circuit and some auxiliary circuits. The master device is the core part of the entire Bluetooth network. It must complete conversion and information sharing between various communication protocols, as well as data exchange functions with external communication networks. It is also responsible for the management and control of each slave device.

5 Conclusion
　　With the progress of society, economic development and improvement of people’s living standards, more and more people need home health care services. The intelligent robot system proposed in this article for digital home health care services has relatively comprehensive functions, and has broad applications in home intelligent robots, smart homes based on Bluetooth technology, and digital hospitals, and has great market potential.