11. USB-FlexRay Bridge

In order to connect ROS with a Myorobot, a USB-FlexRay bridge is provided. This system is illustrated in Fig. 11.1. To connnect to the PC, a mini-USB lead is necessary. The bridge board is also supplied with 24V, which should be the same voltage source that supplies the Myorobot to establish a common ground connection. The connection to the Myorobot, i.e., via the MYO-Ganglions, is established through a 2-wire FlexRay interface.


Fig. 11.1 The Myorobotics USB-FlexRay Bridge

FlexRay is a differential serial bus and the FlexRay cables used for a Myorobot are a simple twisted pair wires, such as the dedicated Flexray cable FLR09YS-YW. The two FlexRay signal lines are referred to as FRp (FlexRay Plus, the positive signal) and FRm (FlexRay Minus, the negative signal). The FlexRay cable provided with your Myorobotic system is shown in Fig. 11.2. The pink cable is used for the FRp and the green cable for the FRm signal. The MYO-Ganglions feature two pairs of FlexRay connections (see Fig. 10.1) which affords easy daisy-chaining of multiple MYO-Ganglions.


Fig. 11.2 The FlexRay cable used for Myorobotic system: green is the FRm signal, pink the FRp signal, i.e. model FLR09YS-YW.