@bill25 Welcome to the RobotShop Community. RobotShop has over 600 suppliers, and two house brands: RobotShop and Lynxmotion. Last year, Lynxmotion release the LSS PRO lineup of all-in-one servo motors:
https://www.lynxmotion.com/ses-pro-modular-robot-system/
Wiring and Space Savings: I love the idea of reducing cable clutter, but do integrated servos really make wiring significantly easier in practice?
Yes, each servo is daisy chained from one to the next, but keep in mind total current consumption.
Communication Protocols: Many models support CANopen, EtherCAT, or Modbus. If you’re using them, which protocol do you recommend for real-time control in robotics?
We reused much of the human-readable LSS protocol to make the servos really easy to use. The back-end is a CAN bus, but proprietary protocol.
Reliability and Heat: Since everything’s in one unit, does heat buildup become a problem under continuous load?
Yes, so quite a bit of development was needed to ensure the passive cooling we use was sufficient to cool them off. We still included several onboard temperature sensors (not including those within the main chips themselves) and thermal safety should they exceed a given temperature.
Brands and Recommendations: I’ve looked at products from JMC, Teknic ClearPath, and IHSV series motors. Any feedback or better alternatives?
Lynxmotion! Granted these look different from those you mentioned above, but they use strain wave gearing for high torque, compact size and incredible accuracy. This having been said, if it’s found that they don’t suit your needs, we’re not here to push them.
In terms of the application, I’m building a 4-DOF robotic arm that needs moderate torque and precision. I want smooth motion and ideally some form of fault detection or feedback if a joint is obstructed.
You mean like… these?
We have a 4DoF planned actually ! You’ll find that without gearing, a stepper motor + electronics won’t produce much torque at all. The size and overall dimensions can be weird too. Users have found creative work-arounds like a single added geardown, timing belts, or and placing the wrist and elbow servo in the base to reduce the load on the arm. Simple calculator for estimating the torque needed at each joint. The servo in the base is always the one which needs to provide the highest torque.
Any insights, experiences, or warnings would be appreciated! Especially from anyone who’s made the switch from traditional servos or stepper systems to these all-in-one solutions.
Does having designed, built and commercialized those types of all-in one modular servos which are used in articulated robot arms give us a little cred? Hopefully 
I want smooth motion and ideally some form of fault detection or feedback if a joint is obstructed.
This would entail current measurement and is largely only applicable to regular DC and BLDC motors, but not steppers. Steppers operate at max current to ensure max torque at all times, even at very low speeds. A work-around is to add an accelerometer to detect impacts. The connections between joints use foam, and there’s an IMU (multi-axis accelerometer and gyro) built into each servo. Our hobby LSS actuators have that feature and would be more “cobot” style. For example a user can set the servo in the gripper to stop at a specific current (which corresponds to a specific torque).
