My robotics team is currently developing a space rover with specific requirements:
Specifications:
- Weight must not exceed 50kg during any mission, and the total weight with all modules cannot exceed 70kg. Our rover specifications are calculated with a generous safety factor.
- Load: 84kg
- Number of Motors: 6 (direct drive)
- Wheel Diameter: 203.2mm (8in)
- Velocity: 2 m/s
- 51.4V 60Ah battery
- 24V BLDC Motors
- Torque: 11.17 Nm (per motor)
- Power: 219.91 W (per motor)
- Max current to each motor: 4.25A
It’s important to note that this is our first attempt at such a project, and we are building it from scratch. Our focus is on getting the first prototype operational, with our current emphasis on finding suitable BLDC motors, motor controllers, and a battery. I have specific concerns about the motor controller – I came across the ODrive v3.6, which seems ideal for our application as we plan to drive each wheel.
My concern is regarding power consumption, as I will need to supply power to each of the three ODrive v3.6 controllers. Will our battery size be sufficient for this kind of connection, or does the configuration amplify consumption, similar to series and parallel connections? Additionally, is the use of three ODrive v3.6 controllers a good approach? While I am aware of the option to purchase six individual Pro or S1 controllers, budget constraints are a consideration. Is it better to use six individual controllers or three ODrive v3.6 controllers?
We’ve encountered challenges in finding suitable motors, particularly as we are seeking an in-hub mounting configuration, leading to conflicts in size and torque requirements.
We appreciate the fact that ODrive controllers can handle all encoder configurations, providing isolation between systems for easier debugging. As our project progresses, autonomous functionality will be essential. Is it straightforward to interface with these motor drivers for autonomous features?
Any recommendations on motor selection or general advice would be greatly appreciated. Although the project has been enjoyable so far, we want to ensure we are approaching it in the most effective manner.