Abstract: There is provided, in a preferred embodiment, a transportation vehicle for transporting an individual over ground having a surface that may be irregular. This embodiment has a support for supporting the subject. A ground-contacting module, movably attached to the support, serves to suspend the subject in the support over the surface. The orientation of the ground-contacting module defines fore-aft and lateral planes intersecting one another at a vertical. The support and the ground-contacting module are components of an assembly. A motorized drive, mounted to the assembly and coupled to the ground-contacting module, causes locomotion of the assembly and the subject therewith over the surface. Finally, the embodiment has a control loop, in which the motorized drive is included, for dynamically enhancing stability in the fore-aft plane by operation of the motorized drive in collection with the ground-contacting module.

Abstract: There is provided, in a preferred embodiment, a device for transporting a human subject over ground having a surface that may be irregular and may include stairs. This embodiment has a support for supporting the subject. A ground-contacting module, movably attached to the support, serves to suspend the subject in the support over the surface. The orientation of the ground-contacting module defines fore-aft and lateral planes intersecting one another at a vertical. The support and the ground-contacting module are components of an assembly. A motorized drive, mounted to the assembly and coupled to the ground-contacting module, causes locomotion of the assembly and the subject therewith over the surface. Finally, the embodiment has a control loop, in which the motorized drive is included, for dynamically enhancing stability in the fore-aft plane by operation of the motorized drive in connection with the ground-contacting module.

Abstract: A polled digital multiport, multidrop system is described. The inbound frame for sending information from remote terminals to the host terminals is arranged such that a plurality of bytes are provided by a first terminal, followed by a guard band, followed by a plurality of bytes provided by a second terminal, followed by another guard band, etc. The guard band permits signalling between the DSU and the OCU which in turn permits the OCU to signal the MJU that no data will be coming from the OCU. In this manner, control mode idle is accomplished and data mode idle is avoided. In addition, because of the guard band, if the delay from a remote site changes, no data will be lost. Means for monitoring the system to follow changes in delay are also provided, and the system can cause a remote location to accommodate a change in delay.

Abstract: Multiport/multidrop computer communication is provided over a single communication facility between a plurality of central stations at a central location their respective remote stations at remote locations. Outbound transmissions are multiplexed from a multiport central modem to compatible multiport remote modems. The central stations are monitored to detect which one or ones have invited a response from a remote station and one central station is selected. A signal is sent to the remote modems indicating the selected central station. The signal is combined with the request to send of the invited remote computer associated with the selected central station to enable use of the return transmission lines. The request to send signal line idle or idle code stations are monitored to detect which central stations have invited a remote. Signaling is by RTS-DCD simulation in commercial modems. Another central station is selected if return transmission does not begin within a timer interval.