Exploratores II

The Quadruped Mobile Robot



Project Objectives

·         Design and implementation of a four-legged walking robot for educational and research purposes

·         Testing motion control - path planning, and gait strategies, based on central program running on a PC or an autonomous operation

·         Simple and cost efficient mechanical and electrical design for easy replication

·         Modular hardware and software structure for efficient further development

Project Background

Since 1989, the Institute of Informatics at the Kandó Polytechnic has incorporated the teaching and research of artificial intelligence and various AI-related courses such as robotics, image processing and neural networks into the curriculum. Students are first become introduced to the theoretical background and the literature. The main emphasis, however, is on an application-oriented approach that requires the students to work on major team projects during three semesters of intensive lab work in which they apply the theoretical knowledge to a specific application. After developing a detailed system specification, they implement and test their design in these lab courses. Several such student projects have been so successful that the results have been presented at international symposiums, exhibitions and conferences.


Physical Features

Lightweight aluminum construction with four-legs, each leg has 3 degrees of freedom



600 mm


400 mm


270 mm

Distance between steps:


140 mm


40 mm




2.1 kg (excluding sensors)

Power supply:

12 V DC


8 - ACOMPS AS-15, torque: 35 Ncm


4 - HITEC HS-615MG, torque: 77 Ncm


5 - 89C51 microcontrollers, one for each leg and one for central control and communication

Tested sensors:

4 - Leuze RT404K/P400 infra reflective sensors, sensitizing range: 100-400 mm


512x512 CCD camera

512x512 CCD camera with PAL lens (The Panomaric Annual Lens is the invention of Prof. Pál Greguss (http://www.manuf.bme.hu/~greguss/)


Path Planning Methods

Recent Developments

·         Development and testing of new gaiting strategies. Faster movements based on dynamic stability, adjusting to different terrain and surfaces.

·         Visual-guided motion control and obstacle avoidance.

·         Integration of optical sensors and visual information into path planning algorithms


Publications about EXPLORATORES

·         Brünner, R., Molnár, A., Varga, L., Vámossy, Z. (1998). Exploratores, Quadruped Robot, In: Proc. of 7th International Workshop on Robotics in Alpe-Adria-Danube Region - RAAD'98 (Slovak Academy of Sciences), (K. Dobrovodskŷ (Ed.)), pp. 215 - 220. Bratislava, Slovakia.

·         Vámossy, Z., Molnár, A., Brünner, R., Varga, L., (1998). Path Planning Methods for a Quadruped Mobile Robot, In: Proc. DAAAM’98, Cluj-Napoca, Romania. (B. Katalinic (Ed.)), DAAAM International, pp. 483-484. Wien, Austria

·         Vámossy, Z., Molnár, A., Brünner, R., Varga, A., (1998). EXPLORATORES II., the Four-Legged Mobile Robot, In: Proc.of International Symposium on Climbing and Walking Robots - CLAWAR’98, (Y. Baudoin (Ed.)) BSMEE. pp. 41-45. Brussel, Belgium

·         Vámossy, Z., Molnár, A. (1999), Obstacle Avoidance for a CLAWAR Machine, In: Proc.of 2nd International Symposium on Climbing and Walking Robots - CLAWAR’99, Portsmouth, (Virk, Randall, Howard (Eds.)),) Professional Engineering Publishing Limited, London, pp.597-603. 1999.

·         Brünner, R., Molnár, A., Varga, L., Vámossy, Z. (1998). Exploratores, négylábú robot, In: XV. Centenáriumi Tudományos Ülésszak KKMF, Vol. Szabályozástechnika-Robottechnika, pp. 36-41., Budapest.

·         A. Molnar, Z. Vamossy: (2001) Navigation of Mobile Robot Using PAL Optic, ICAR 2001 Workshop, (accepted)


Contact Information