Controlling a system with redundant degrees of freedom. I. Torque distribution in still standing stick insects
- 92 Downloads
- 4 Citations
Abstract
The question is investigated as to how a stick insect solves the task of distributing its body weight onto its six legs, i.e., how are the torques coordinated that are produced by the 18 joints (3 per leg). Three-dimensional force measurements of ground reaction forces have been used to calculate the torques developed by each of the 18 joints. Torques were found to change considerably although the body and the legs of the animal did not move. This result implies a tight cooperation between the 18 joint controllers. Indeed, in each individual experiment, strong correlations could be observed between specific pairs of joints. However, in spite of thorough analysis, no general correlation rules between torques could be detected. The only common attribute found for all experiments was that high absolute torques observed at the beginning of the experiment tend to converge to some minimum over time. Thus, the insects tend to decrease the torques while standing still, but do not use fixed rules. Rather they appear to exploit their extra degrees of freedom and produce time courses that can strongly vary between experiments. Possible mechanisms underlying this behaviour are discussed in a companion paper [Lévy and Cruse (2008) Controlling a system with redundant degrees of freedom: ii. solution of the force distribution problem without a body model, submitted].
Keywords
Stick insects Standing Force distribution Torque distribution Redundant degree of freedomAbbreviations
- DoFs
Degrees of freedom
- mN
Millinewton
- mN mm
Millinewton millimeter
- s
Second
Notes
Acknowledgments
This work was supported by the DFG grant no. Cr 58/11- 1,2 and by the Center of Excellence “Cognitive Interaction Technology” no. 277.
References
- Bartling C, Schmitz J (2000) Reaction to disturbances of a walking leg during stance. J Exp Biol 203(7):1211–1223PubMedGoogle Scholar
- Bässler U (1985) Proprioceptive control of stick insect walking. In: Gewecke, Wendler (eds) Insect locomotion. Paul Parey, pp 43–48Google Scholar
- Beer R, Quinn R, Chiel H, Ritzmann R (1997) Biologically inspired approaches to robotics: what can we learn from insects? Commun ACM 40(3):30–38CrossRefGoogle Scholar
- Bernstein N (1967) the co-ordination and regulation of movements. Pergamon Press, OxfordGoogle Scholar
- Burns M (1973) The control of walking in orthoptera. i. Leg movements during normal walking. J Exp Biol 58(1):45–58Google Scholar
- Cheng F, Orin D (1990) Efficient algorithm for optimal force distribution—the compact-dual lp method. IEEE Trans Rob Autom 6(2):178–187CrossRefGoogle Scholar
- Cruse H (1976) The function of the legs in the free walking stick insect, Carausius morosus. J Comp Physiol 112(2):235–262CrossRefGoogle Scholar
- Cruse H (1979) A new model describing the coordination pattern of the leg of a walking stick insect. Biol Cybern 32(2):107–113CrossRefGoogle Scholar
- Cruse H (1981) Is the position of the femur-tibia joint under feedback control in the walking stick insect? i. Force measurements. J Exp Biol 92(1):87–95Google Scholar
- Cruse H (1985a) The influence of load, position and velocity on the control of leg movement of a walking insect. In: Gewecke, Wendler (eds) Insect locomotion. Paul Parey, pp 19–26Google Scholar
- Cruse H (1985b) Which parameters control the leg movement of a walking insect? ii. The start of the swing phase. J Exp Biol 116(1):343–362Google Scholar
- Cruse H (1990) What mechanisms coordinate leg movement in walking arthropods? Trends Neurosci 13(1):15–21PubMedCrossRefGoogle Scholar
- Cruse H, Bartling C (1995) Movement of joint angles in the legs of a walking insect, Carausius morosus. J Insect Physiol 41(9):761–771CrossRefGoogle Scholar
- Cruse H, Knauth A (1989) Coupling mechanisms between the contralateral legs of a walking insect (Carausius morosus). J Exp Biol 144(1):199–213Google Scholar
- Cruse H, Pflüger H (1981) Is the position of the femur-tibia joint under feedback control in the walking stick insect? ii. Electrophysiological recordings. J Exp Biol 92(1):97–107Google Scholar
- Cruse H, Schmitz J (1983) The control system of the femur-tibia joint in the standing leg of a walking stick insect Carausius morosus. J Exp Biol 102(1):175–185Google Scholar
- Cruse H, Schwarze W (1988) Mechanisms of coupling between the ipsilateral legs of a walking insect (Carausius morosus). J Exp Biol 138(1):455–469Google Scholar
- Dean J (1989) Leg coordination in the stick insect Carausius morosus: effect of cutting thoracic connectives. J Exp Biol 145(1):103–131Google Scholar
- Dean J (1991) Effects of load on leg movements and step coordination of the stick insect Carausius morosus. J Exp Biol 156(1):449–472Google Scholar
- Delcomyn F (1971) The locomotion of the cockroach Periplaneta americana. J Exp Biol 54:443–452Google Scholar
- Delcomyn F (1985) Sense organs and the pattern of motor activity during walking in the american cockroach. In: Gewecke, Wendler (eds) Insect locomotion, Paul Parey, pp 87–96Google Scholar
- Espenschied K, Quinn R, Chiel H, Beer H (1996) Biologically based distributed control and local reflexes improve rough terrain locomotion in a hexapod robot. Rob Auton Syst 18:59–64CrossRefGoogle Scholar
- Evans M (1977) Locomotion in the coleoptera adephaga, especially carabidae. J Zool 181:189–226CrossRefGoogle Scholar
- Franklin R (1985) The locomotion of hexapods on rough ground. In: Gewecke, Wendler (eds) Insect locomotion. Paul Parey, pp 69–78Google Scholar
- Full R, Tu M (1990) Mechanics of six-legged runners. J Exp Biol 148:129–146PubMedGoogle Scholar
- Full R, Tu M (1991) Mechanics of a rapid running insect: two-, four- and six-legged locomotion. J Exp Biol 156:215–231PubMedGoogle Scholar
- Full R, Blickhan R, Ting L (1991) Leg design in hexapedal runners. J Exp Biol 156:369–390Google Scholar
- Full R, Yamauchi A, Jindrich D (1995) Maximum single leg force production: cockroaches righting and running on photoelastic gelatin. J Exp Biol 198:2441–2452PubMedGoogle Scholar
- Goldfarb D, Idnani A (1983) A numerically stable dual method for solving strictly convex quadratic programs. Math Program 27(1):1–33CrossRefGoogle Scholar
- Goldman D, Chen T, Dudek D, Full R (2006) Dynamics of rapid vertical climbing in cockroaches reveals a template. J Exp Biol 209:2990–3000PubMedCrossRefGoogle Scholar
- Graham D (1972) A behavioural analysis of the temporal organization of walking movements in the first instar and adult stick insect. J Comp Physiol 81(1):23–52CrossRefGoogle Scholar
- Harris J, Ghirardella H (1980) The forces exerted on the substrate by walking and stationary crickets. J Exp Biol 85:263–279Google Scholar
- Hughes G (1952) The coordination of insect movement. i. The walking movements of insects. J Exp Biol 29:267–284Google Scholar
- Jander J (1985) Mechanical stability of stick insects when walking around curves. In: Gewecke, Wendler (eds) insect locomotion, Paul Parey, pp 33–42Google Scholar
- Jindrich D, Full R (1999) Many legged maneuverability: dynamics of turning in hexapods. J Exp Biol 202:1603–1623PubMedGoogle Scholar
- Jindrich D, Full R (2002) Dynamic stabilization of rapid hexapedal locomotion. J Exp Biol 205:2803–2823PubMedGoogle Scholar
- Klein C, Kittivatcharapong S (1990) Optimal force distribution for the legs of a walking machine with friction cone constraints. IEEE Trans Rob Autom 6(1):73–85CrossRefGoogle Scholar
- Kozacik J (1981) Stepping patterns in the cockroach Periplaneta americana. J Exp Biol 90:357–360Google Scholar
- Kram R, Wong B, Full R (1997) Three dimensional kinematics and limb kinetic energy of running cockroaches. J Exp Biol 200:1919–1929PubMedGoogle Scholar
- Lafosse R (1989) Proposal for a generalized canonical analysis. Multiway Data Anal 269–276Google Scholar
- Lafosse R, TenBerge J (2005) A simultaneous concor algorithm for the analysis of two portioned matrices. Comput Stat Data Anal 50(10):2529–2535CrossRefGoogle Scholar
- Lévy J, Cruse H (2008) Controling a system with redundant degrees of freedom: ii. Solution of the force distribution problem without a body model (in press)Google Scholar
- Manly B (2004) multivariate statistical methods. Chapman & Hall, LondonGoogle Scholar
- Nahon M, Angeles J (1992) Real-time force optimization in parallel kinematic chains under inequality constraints. IEEE Trans Rob Autom 8(4):439–450CrossRefGoogle Scholar
- Nakamura Y, Nagai K, Yoshikawa T (1987) Mechanics of coordinative manipulation by multiple robotic mechanism. IEEE Trans Rob Autom 4:991–998Google Scholar
- Rao C, Toutenburg H, Shalabh, Heuman C (2007) Linear models and generalizations. Springer, HeidelbergGoogle Scholar
- Schneider A, Cruse H, Schmitz J (2008) Winching up heavy loads with a compliant arm: a new local joint controller. Biol Cybern (in press)Google Scholar
- Spong M, Hutchinson S, Vidyasagar M (2006) Robot modeling and control. Wiley, LondonGoogle Scholar
- Ting L, Blickhan R, Full R (1994) Dynamic and static stability in hexapedal runners. J Exp Biol 1997:251–269Google Scholar
- Zollikofer C (1994) Stepping patterns in ants. J Exp Biol 192:95–127PubMedGoogle Scholar