Mastering BEAR Actuators 03: Wireless E-STOP Setup & BEAR Actuator Logic

In this talk

1. 0:28

   BEAR actuator states

   The presenter describes four states: 0 disables the actuator and clears latched errors, 1 enables normal movement, 3 provides damping after recoverable errors, and 2 blocks activation after a critical error. These states indicate whether the actuator can move and how it responds to faults.

2. 1:06

   E-Stop behavior and recovery

   The E-Stop activates when its terminal is not held at ground. If the BEAR is active, it enters hardware damping; writing 3 to the status register can also trigger damping. To recover, ground the E-Stop terminal, then write 0 to disable the actuator and reset its error code.

3. 1:39

   Receiver wiring and indicators

   The receiver’s signal and ground connect to the BEAR bus. It can use USB-C, 5 V, or 3.3 V power, with only one source connected at a time; using 3.3 V requires bridging the EXT 3.3 V jumper. A purple RGB flash signals disturbance, while three LEDs indicate E-Stop, connection, and power.

4. 2:25

   Kit connections and operation

   The kit includes a remote, receiver, BEAR-to-E-Stop adapter, PH 3P cable, and transmitting button; the button’s black base must be printed separately. The adapter has two six-pin BEAR ports, a two-pin 3.3 V input, and a three-pin E-Stop port. For 5 V power, the lower port beneath the E-Stop connection is used; confusing the two similar ports can cause a short.

5. 4:27

   Licensing and resources

   The wireless E-Stop software is offered under GPLv3 for academic and hobby use, while commercial integration requires a separate license. The presenter points users to Westwood Robotics’ GitHub repository for code examples and schematics, and says the kit is available through the company’s online store.