Improving estimations of a robot s position and attitude w ith accelerom eter enhanced odometry

Transcription

1 4 2 Vol CAA I Transactions on Intelligent System s Ap r , 2, 3 (1., , , ) :,,. Gyrodometry,,,,,. 1 /3, 1 /6,. : Gyrodometry : TP242 : A : (2009) Improving estimations of a robot s position and attitude w ith accelerom eter enhanced odometry WANG Xiao2yu 1, YAN J i2hong 2, XU L i2hong 3 ( 1. DFH Satellite Company L td., Beijing , China 2. Robotics Institute, Harbin Institute of Technology, Harbin , China 3. Number 2 Scientific Research Institute, Number 304 Factory, Changzhi , China) Abstract:Unp redictable events can occur in the navigational p rocesses of two2wheeled self2balancing robots, such as wheel2slippage, interaction w ith obstacles, and bump s. These invalidate position and attitude estim ates. There2 fore, an imp roved method was developed for accurate positioning of robots. ometer data to the imp roved Gyrodometry method, fusing encoder data with inertial sensor data. The accodometry m ethod adds acceler2 This method elim i2 nates the effect of non2systematic errors on robot position and attitude estimation and reduces ill2effects due to inher2 ent drift of the gyro and accelerometer. A s a result, positional accuracy is greatly imp roved. Experimental results showed that positional errors decrease by one2third and orientation errors decline by one2sixth, verifying the effec2 tiveness of the accodometry method. Keywords: position and attitude estimation accodom etry m ethod Gyrodometry method,. 2 :, [ 123 ].,,, : : 863 (2006AA04Z245). :. E2mail: wxyhit197745@ yahoo. com. cn..,.,.,,, [ 427 ]. Borenstein [ 8 ] UMBmark (University ofm ichigan benchmark test),

2 170 4,. [ 2 ] UMBmark,., Borenstein [ 9 ] Gy2 rodometry,,,., [ 10 ]., ( ),.,, ( accelerometer2 odometry), Gyrodometry,. 1,,.. 2 : 1) :. 2) :.,.,.,. 2,,, Fig. 1 Schematic diagram of sensors 3,,. 3. 1, D ( D )., 2, D,,.,, 2. L 1, L 2, L 3, L 4, F. 2 Fig. 2 Schematic diagram of odometry error,,

3 2, : 171,. : x., z : ( t) = arctan L ped 1 ( t) - L ped2 ( t) D ped ( t) = arctan L us 1 ( t) - L us2 ( t) D us co s ( t) x ( t) = [L us ( t) + D us1 ]cos ( t) cos ( t) - D us2 sin ( t) co s ( t) z ( t) = [L us ( t) + D us1 ]co s ( t) sin ( t) - D us2 sin ( t) sin ( t). : L ped1 L ped2 1 2, D ped 2, L us1 L us2 1 2, D us 2, L us ( t) = arctan L ped 1 ( t) - L ped2 ( t) D ped ( t) = arctan L us 1 ( t) - L us2 ( t) D us cos ( t) (1), D us1 D us2. 2 ( 1), : x ( t) = V ( t) t - [L us ( t) + D us1 ]co s ( t) cos ( t) - D us2 sin ( t) cos ( t) z ( t) = [L us ( t) + D us1 ]cos ( t) sin ( t) - D us2 sin ( t) sin ( t) - (L us0 + D us1 ). :,, x X, z Z, V, L us0., Z,, X Z, X.,,.,,,,,,., D,, D m / s, 3 m, 10 m s, 0. 5 m (2). 3,,,,,.,. 3 Fig. 3 The position curves of the single obstacle negotiation,,,

4 172 4,.,, Fig. 4 The position error change curves of the single obsta2 cle negotiation,. 4 Gyrodometry,. UMBmark, Gyrodometry, H ITBot m, 2. 0 kg, 0. 2 m, m, ,.,.,.,.., 3. 4, D odo, D acc, D ao = D odo - D acc. D ao D thres, D ao > D thres, (3), D acc. : D ao < D thres, (4), D odo.,, 5 H ITBot Fig. 5 Two2wheeled self2balanced robot2h ITBot 4. 2,,, 1, 6. 1 Table 1 Num ber and d im en sion of obstacles /mm , m 2, m., Gyrodometry 0. 1 m

5 2, : 173,., : odop = D odo - D real, (5) acc = D acc - D real, (6) ao = D ao - D real. (7) :D odo D acc D ao, D real, odop acc ao. 1 /3, 1 /6. 7 Fig. 7 The position curve of obstacle negotiation after cor2 rection 6 Fig. 6 Schematic diagram of straight line obstacle negotiation 8 Fig. 8 The position error of obstacle negotiation after cor2 rection 4. 3 D thres 0. 4 mm thres 0. 05, 7, 8, Gy2 rodometry 9. Gyrodometry,. Gyrodometry 0. 4, 2. 2,,,. 4,, 4 mm. Gyrodometry, 9 Fig. 9 The orientation error of obstacle negotiation after correction 5,,.

6 174 4,.. : [ 1 ],,. [ J ]., 2004, 26 (5) : WANG W eihua, X IONG Youlun, SUN Ronglei. M easure2 ment and calibration of systematic errors of odometry [ J ]. Robot, 2004, 26 ( 5) : [ 2 ]L I Yan, GAO Feng, L IN Tingqi, et al. Study on multi2sen2 sor data fusion for the wheeled mobile robot [ C ] / / Proceed2 ings of the 5 th World Congress on Intelligent Control and Automation. Hangzhou, China, 2004: [ 3 ]OJEDA L, BORENSTE IN J. FLEXnav: fuzzy logic expert rule2based position estimation for mobile robots on rugged terrain [ C ] / / Proceedings of the 2002 IEEE International Conference on Robotics and Automation. W ashington DC, USA, 2002: [ 4 ]BARSHAN B, DURRANT2WHYTE H F. Inertial navigation system s for mobile robots[ J ]. ics and Automation, 1995, 11 ( 3) : IEEE Transactions on Robot2 [ 5 ],,. [ J ]., 2005, 27 (3) : WANG W eihua, X IONG Youlun, SUN Ronglei. An experi2 mental calibration method for wheel2slippage in mobile ro2 bots[ J ]. Robot, 2005, 27 (3) : [ 6 ]CHUNG H, OJEDA L, BORENSTE IN J. Accurate mobile robot dead2reckoning with a p recision2calibrated fiber op tic gyroscope[ J ]. tion, 2001, 17 ( 1) : IEEE Transactions on Robotics and Automa2 [ 7 ] ANTONELL I G, CH IAVER IN I S, FUSCO G. A calibra2 tionmethod for odometry of mobile robots based on the least2 squares technique: theory and experimental validation [ J ]. IEEE Transactions on Robotics, 2005, 21 ( 5) : [ 8 ] BORENSTE IN J, FENG L. UMBmark: a benchmark test for measuring odometry errors in mobile robots [ C ] / /1995 SP IE Conference on Mobile Robots. 1995: Philadelphia, USA, [ 9 ]BORENSTE IN J, FENG L. Gyrodometry: a new method for combining data from gyros and odometry in mobile robots [ C ] / / Proceedings of the 1996 IEEE International Confer2 ence on Robotics and Automation. M inneapolis, MN, USA, 1996: [ 10 ]BORENSTE IN J, FENG L. Measurement and correction of systematic odometry errors in mobile robots [ J ]. IEEE Transactions on Robotics and Automation, 1996, 12 ( 6) : :,, 1977,,,, 13.,, 1974,,,, 20.,, 1973,,.