| OCR Text |
Show program is to make the input language entirely stylus-and-tablet oriented. The need for this becomes obvious to a user attempting to exercise the Teletype-input options, such as by varying the distance of the stage. Though the Teletype is located immediately next to the tablet and the user, it is disconcerting to alternate between input devices. Programming this change would not be difficult. Another change concerns matrix multiplication. When a rotation matrix undergoes a number of computer multiplications, as it do;3S in this program, the orthogonality properties are lost because of computer truncation. Mahl [15] has devised a correction equation which restores orthogonality to the rotation matrix. It is a rapidly converging, iterative scheme based on a Taylor's series. As the numDer of matrix multi-plications is increased in expanding the model, incorporation of this scheme into the program might be considered. III.2 Anthropometric Considerations A truer representation of the mechanical relationships of the human body, or in other words, a better stick figure, should be an early goal of one improving the prototype. III.2-1 Constraints on Movement of Joints In the prototype program, crude approximations of the natural constraints on joint movements are used, the model being a crude approximation of a human figure. These limits on joint movements were assumed to be constant, although in reality most constraints will vary 31 *i~mcmmmjmmmmmmm mmmm tumwi » ■n» I'm i ■•*'•»■ ^-quf.- - -1 HI, r -'am-p-m |
