I think you should first implement your idea on Raspberry Pi. I think so because:
1. There are Ant+ usb sticks available
2. This Ant+ sticks also provide the python code for your need.
3. Python lib for MPU6050 is also avialable.
4. There are board available to control motor via RPi.
If you are successful in implementing this proof of concept, then I would suggest you to go for dedicated circuit containing microcontroller, which reads Ant+ and Gyro signal and operate motors.
I provide all this services including RPi development and Microcontroller based dedicated development. I am also experienced with:
- Microcontrollers (Atmel, Cypress PSoC, Microchip, STM32).
- Arduino, Raspberry (Python) and Beaglebone (Python).
- GSM modules like SIM900-800-800C.
- Ethernet modules like W5100, W5500 (Wiznet) and Microchips Ethernet controllers.
- Wifi Modules (espressif).
- FreeRTOS
- Schematic and PCB design using Proteus.
- MODBUS
- RS485,RS232
- CAN Bus
- REST and MQTT like protocols.
So you may use us to implementing your idea for your product. Best regards. More on chat. We can bargain over the charges also once you clarify the whole need.