Since moving to FreeRTOS Renoster's control system lost the use of Timer1 thus the ability to control 4 servos using PWM. After some scouring on the net using a 4017 decade counter seem to be the solution to get that functionality back.

Renoster requires a fairly integrate control system, with several tasks required to run almost simultaneously, e.g. position calculation, way point tracking, mapping etc. and others need to be able to interrupt those in the event of possible danger, e.g. collision detection, tilt detection etc. A preemptive multitasking OS such as FreeRTOS provides all these features.

Dropped the ATMega32 control board, now using a WiringIO board with custom perfboard IO breakout header, will do a proper PCB a bit later once it is all working.

Finally got time to finish the odometry and basic way point system. It still has a pretty big error, but some more tinkering should fix that.

Renoster has 4 Lynxmotion GHM-15 gear head motors each with a hall effect quadrature encoder. The quadrature encoders outputs two square waves 90 degrees apart (see Fig. 1) as the motor turns. Using these signals one can determine the speed and direction of the motor and from that the robots relative movement.

A quick summary of how Renoster started and where it is going.