No abstract

The planar motion of a charged particle in a logarithmic potential is studied in the context of an electrostatic cylindrical spectrometer. The trajectory is found to be bounded and to have a period, 2P, lying in the interval 7~ < 2P< WT. General spectrometer design considerations are discussed, and a method for calculating resolution is described. A specific example of spectrometer design is included.

Forcetorque sensor Systems capable of simultaneously measuring all six spatial degrees of freedom on solid bodies are not very widespread in &e medical field, panicularly because of the hitherto unacceptably large external dimensions. A sensor based on the strain gauge technique has been developedwith a diameter of only 32.5 mm and height of 29 mm. T h e miniaturised supporting framework for the strain gauges has been cast in a single piece from a wax-plasric model by the one-way mould principle. A sensitivity of 10 mN with an upper limit of 50 N is attained. 0143-08151921030241 + 08 802.50 0 1992 lnsrirute of Physical Sciences in Medicine 24 1