This paper presents the estimation of the frictional coefficient of the wheel-legged robot with hip joint actuation producing maximum tractive force. Slip behavior for wheel-legged robot is analytically explored and physically understood by identification of the non-slip condition and derivation of the torque limits satisfying it. Utilizing results of the analysis of slip behavior, the frictional coefficients of the wheel-legged robot during stance phase are numerically estimated and finally this paper suggests the pseudo-algorithm which can not only estimate the frictional coefficients of the wheel-legged robot, but also produce the candidate of the touch down angle for the next stance.

This paper deals with researching and designing the fastening parts to be used in order to assemble various Teaching Aids Robots (or Hands-on Robots) with originally incompatible parts supplied by different manufacturers. The suggested fastening parts provide the compatibility among Teaching Aids Robots even though the educational robot customers use incompatible parts from different companies. The designed fastening parts are classified into four set groups such as frame set, sliding-bar set, connector set, and set of chuck and rivet/bolt. Each set of the fastening parts reflects the needs collected from the users, and then some portion of new idea has been added to implement the needs. In this paper, the examples of the Teaching Aids Robots which are assembled with both commercial parts and the designed parts are presented in order to evaluate the compatibility and usability of the suggested fastening parts. As a result, both compatibility and usability of the fastening parts suggested in this paper were proved. The designed fastening parts have been distributed to more than 100 elementary schools nationwide.

Radio Frequency Identification (RFID) is an automatic identification method. Information such as identification, logistics history, and specification of products are written and stored into the memory of RFID tags (that is, transponders), and retrieved through RF communication between RFID reader device and RFID tags. RFID systems have been applied to many fields of transportation, industry, logistics, environment, etc in order to improve business efficiency and reduce maintenance cost as well. Recently, some research results are announced in which RFID devices are combined with other sensors for mobile robot localization. In this paper, design of multi-protocol baseband for RFID reader device is proposed, and the baseband modem is implemented into SoC (System On a Chip). The baseband modem SoC for multi-protocol RFID reader is composed of several IP (Intellectual Property) blocks such as multi-protocol blocks, CPU, UART(Universal Asynchronous Receiver and Transmitter), memory, etc. As a result, the SoC implemented with FPGA(Field Programmable Gate Array) is applied to real product. It is shown that the size of RFID Reader module designed with the FPGA becomes smaller, and the SoC chip price for the same function becomes cheap. In addition, operation performance could be the same or better than that of the product with no SoC applied.