Segment Information - Schedule of Segment Information for Operation Statement (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2018	Jul. 01, 2017	Jun. 30, 2018	Jul. 01, 2017	Dec. 30, 2017
Revenue	$ 13,872	$ 15,966	$ 27,059	$ 28,440
Gross profit	$ 2,253	$ 2,513	$ 3,665	$ 4,244
Gross Profit Margin	16.20%	15.70%	13.50%	14.90%
SG&A	$ 2,869	$ 3,057	$ 5,451	$ 6,462
Operating income (loss)	(616)	(544)	(1,786)	(2,218)
Other income (expense)	(373)	52	(378)	55
Interest expense, net	(5)	(11)	(14)	(76)
Tax benefit (expense)	(2)	392	14	467
Net loss	(992)	(895)	(2,192)	(1,772)
Total Assets	26,978		26,978		$ 29,252
EPCM [Member]
Revenue	6,652	5,948	11,747	11,577
Gross profit	$ 1,330	$ 837	$ 1,746	$ 1,331
Gross Profit Margin	20.00%	14.10%	14.90%	11.50%
SG&A	$ 531	$ 528	$ 957	$ 1,097
Operating income (loss)	799	309	789	234
Total Assets	9,179		9,179		5,976
Automation [Member]
Revenue	7,220	10,018	15,312	16,863
Gross profit	$ 923	$ 1,676	$ 1,919	$ 2,913
Gross Profit Margin	12.80%	16.70%	12.50%	17.30%
SG&A	$ 663	$ 668	$ 1,367	$ 1,408
Operating income (loss)	260	1,008	552	1,505
Total Assets	11,982		11,982		12,485
Corporate [Member]
Revenue
Gross profit
Gross Profit Margin	0.00%	0.00%	0.00%	0.00%
SG&A	$ 1,675	$ 1,861	$ 3,127	$ 3,957
Operating income (loss)	(1,675)	$ (1,861)	(3,127)	$ (3,957)
Total Assets	$ 5,817		$ 5,817		$ 10,791