Introduction: 3ft DIY Actobotics Slider for EMotimo Spectrum: Part III
This is part III of the slider build where I motorize the slider for time lapse and video sequences using the eMotimo Spectrum ST4. Some of the same images from step 1 are repeated here so you don't have to go back and forth between build threads. If you only want the video slider, you can go back to step 1, where I show how the slider was constructed using Actobotics Parts from servocity.com.
- Part One: Building the Actobotics Slider
- Part Two: Adding Motion using a Syrp Genie Mini
- Part Three: Adding Motion using an eMotimo Spectrum ST4 (See Below)
Like I said previously, I already have a 6 foot slider from dynamic perception that I use with the eMotimo Spectrum. It is a bit big, bulky and somewhat unwieldy, so I started researching finding a smaller alternative in the 3 foot range. eMotimo has a iFootage Shark S1 slider with motor on their site for $899. I knew from previous builds that I could probably build my own with Actobotics parts for a lot less than that. Retail numbers for this build are just under $350 including the parts and stepper motor. I waited until ServoCity had a 15% off coupon to save me around $40. For me, a ton of the enjoyment comes from the actual build process. In part 2, we experimented with adding motion using the Syrp Genie Mini, which was designed for rotational time lapse sequences, and we modified the slider to allow for lateral slider movement. That was more for fun than anything, to see if it would work. Now, in Part III and final stage of this build, we'll finalize the design to be used with the eMotimo Spectrum ST4.
*** This instructable assumes that you already have a motion control system like the eMotimo Spectrum and a camera capable of doing time lapse sequences.
Step 1: Actobotics Slider Rail Parts
When I began this build, the Acobotics x-rail needed to be tapped with a tap and die set. They now sell these rails pre-tapped, so you won't need to do it yourself.
Step 2: Actobotics V-Wheel Camera Carriage
You'll need 2 of the v-wheel kits for this build. To attach the wheels to the pattern plates, you'll need the X-rail roller brackets. The pattern plates are used to hold the camera. The picture shows a generic quick release plate, as eventually I'll be mounting the eMotimo Spectrum time lapse controller. You'll see in later pics and video, that I have a tripod head mounted for demonstration purposes. I used a spacer to get the quick release plate some room so the tightening knob could be accessed.
Step 3: Actobotics Drive System Parts
I will be using a belt drive system to move the carriage along the slider. The pinion pulley is attached to a 1/4" D-shaft. I then use shaft mount bevel gears so that the motor is perpendicular to the shaft. You could eliminate a few parts by having the motor mounted directly to the D-shaft without the bevel gears. The trickiest part was the installation of the belt and pinion pulley's, and getting the belt installed with plenty of pressure so there isn't any slack. I got the belt as tight as I could get it by hand, and then installed the left pillow block with a single set of screws so that it would pivot. I then used a screw driver to apply pressure to the D-shaft to get it into place with plenty of tension on the belt.
The big difference between this type of slider and something like the Dynamic Perception Stage zero slider is that the motor is mounted to the slider frame itself, versus riding along on the carriage. This just means that you have to have a cable long enough for the full travel of the carriage.
Here is a list of parts specific to the motion components of the slider.
- 1/4" ID x 1/2" OD Flanged Ball Bearings
- 1/4" Stainless Steel D-Shafting
- 2 x Shaft Mount Bevel Gears
- 6mm to 1/4" Set Screw Coupler
- 4 x 1/4" Bore Side Tapped Pillow Blocks
- Aluminum Set Screw Collars
- HD Premium Planetary Gear Motor Mount, Tapped
- 6-32 Socket Head Machine Screws
- Shafting and Tubing Spacers
- 2 x 15 Tooth Pinion Pulley 0.250"
- Pre-Cut Timing Belt
- XL Belt Mount A
- Hub Spacer
Step 4: Stepper Motor Options
The easiest way to get a stepper motor that works with the eMotimo Spectrum ST4 is to buy it directly from the eMotimo website. They currently only have 3 options, two of which are currently out of stock. Each one will cost you $96 plus the cost of the cable. I chose to buy my motors from stepperonline, where these geared stepper motors run about $30. You'll have to get the connector for the ST4, which will add an additional $5 plus shipping. I want to be able to use this motor for other projects, so I also purchased the extension cable from eMotimo for $25.
*** I plan on using this slider for time lapse sequences only, and doubt I would use it for video slider movements. It does take a bit of time for the carriage to move from one end of the slider to the other during set up. You could get a 5:1 stepper motor to make the movements faster. I already had the 14:1 motor, so I went with it.
*** Please note that the Planetary gear motors from stepperonline do not match up to the actobotics planetary gear motor mounts. I had to modify the mount and expand the holes a bit to get it to work. There are some pricier options on the stepper motor online that use NEMA 23 patterns, and that might be a better solution when pairing with the Actobotics parts.
Step 5: Final Product Pics
I will use this with either my Canon 5D Mark III or my Sony RX100 V for motion time lapse sequences. The Actobotics parts may not look as professional as some of the commercial sliders out there, but it performs great. I'll try and post a time lapse in the next week or so.
Step 6: Results in Action
This first video was shot taking pics every 5 seconds over an hour. The analog clock is there to show you the time that has passed. This is just an example of what the slider looks like in action.
The rest of the videos were done from my driveway as an example of motion from right to left across the slider. I still plan on running this through LRTimelapse to smooth things out, but wanted to get something up on the instructable sooner than later.